Patent Publication Number: US-3970620-A

Title: Polyvinylchloride compositions for frothing

Description:
This is a continuation of application Ser. No. 437,054, filed Jan. 28, 1974, now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to polyvinylchloride homopolymer and copolymer foam compositions prepared by frothing. These compositions contain silicone surfactant frothing agents and oleophilic frothing aids. 
     2. Description of the Prior Art 
     Techniques for the preparation of polyvinylchloride homopolymer and copolymer foam compositions from plastisols are well known in the polymer art. Also, the literature on polyvinylchloride and acetate modified polyvinylchloride resin plastisol preparation is quite extensive. Reference may be made to the following publications: 
     Boehm and Dietz, &#34;Vinyl Froth Foams Via the Oakes Continuous Mixer&#34;, Diamond Shamrock Chemical Company Technical Service Information Report No. 3-71, Apr. 30, 1971. 
     Boehm and Dietz, &#34;The `Ulok` PVC Carpet Backing System&#34;, Diamond Shamrock Chemical Company Technical Service Information Report No. 4-71, May 5, 1971. 
     Simoneau, &#34;Silicone Surfactants in Mechanically Frothed Vinyl Plastisol Foams&#34;, Rubber World, p. 49, August 1970. 
     Renshaw and Garlick, &#34;How to Back Carpets with PVC&#34;, SPE Journal, Vol. 28, p. 21 (1972). 
     Keil and Webb, &#34;Mechanically Frothed Vinyl Plastisol Foams&#34;, Journal of Cellular Plastics, Vol. 6, No. 4, p. 3, July/August, 1970. 
     Polyvinylchloride (PVC) foam for use as carpet and rug backing and in other markets has certain inherent advantages over other foamed polymers. PVC foams for rug and carpet backing have high tensile and tear strengths; they are more resistant to scuffing, and they have stronger tuff-lock. Also, of significant importance, PVC foams are more fire retardant than other foam polymers. 
     There are three general methods for producing foam from plastisols . . . compressed gas, chemical blowing agents, and frothing (mechanical whipping). In the frothing method, the most widely used method for producing fine open cell foam, PVC foam is produced by mechanical whipping of the plastisol to incorporate air into the plastisol and then fusing the foam at a relatively low temperature of about 270° to about 290°F. About the only disadvantage of this relatively simple frothing method is the high cost of the silicone surfactant frothing agent. 
     Additional information on the preparation of PVC foam compositions by frothing can be found in U.S. Pat. No. 3,511,788 -- Keil -- issued May 12, 1970. This patent describes the preparation of froths using silicone surfactant frothing agents and the use of these foams in various applications including the coating of substrates such as rugs and carpets. 
     SUMMARY OF THE INVENTION 
     Polyvinylchloride compositions for frothing contain 
     1. a foamable plastisol which is a mixture of 
     a. a particulate resin such as a vinyl resin homopolymer or a resinous copolymer containing a major portion of the vinyl resin and a minor portion of a copolymerizable monomer, 
     b. one or more high boiling organic liquid plasticizers which is substantially a non-solvent for the particulate resin at room temperature but is capable to dissolving the particulate resin at an elevated temperature to form a single phase material which upon cooling to room temperature is a solid material, 
     2. from about 1 to about 5 phr of one or a mixture of silicone frothing agents, and 
     3. from about 5 to about 10 phr of one or a mixture of frothing aids which is a phosphate ester, phosphite ester, borate ester, organic nitrogen compound or organic nitrogen-sulfur compound. 
     These compositions are prepared by mixing the plastisol, frothing agent and frothing aid. The compositions are prepared from foamable polyvinylchloride homopolymer and copolymer resin plastisols. These plastisols include vinyl chloride homopolymers and copolymers thereof. The frothing agents are silicone surfactants. Suitable frothing aids include simple and complex organic phosphate esters and phosphite esters; organic nitrogen compounds such as amines, aminoamides, alkanolamides, imidazolines, quaternaries, and organic nitrogen-sulfur compounds, simple and complex organic borate esters such as 2-ethylhexyl borate, tri-hexylene glycol biborate, and tricresyl borates. These foam compositions are mechanically whipped to produce foams or froths, which are used in a variety of applications including coatings for substrates such as carpets and rugs. The frothing aids are used to control froth viscosity. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The polyvinylchloride (PVC) foam compositions disclosed in this invention are mixtures of a foamable plastisol, a frothing agent and a frothing aid. The compositions may also contain fillers, pigments and vinyl resin stabilizers. The plastisol is a dispersion of finely divided vinyl resin in a plasticizer. 
     Polyvinylchloride homopolymers and copolymers for plastisols are specifically designed vinyl resins for this purpose. With molecular weights in the 50,000-120,000 range, they have the particle size distribution and surface characteristics to form fluid plastisols with plasticizers. Normally they are called paste or dispersion resins. 
     The most commonly used copolymers contain 80 to 98% by weight polyvinylchloride and 2 to 20% by weight polyvinyl acetate. 
     Other useful PVC copolymers contain the indicated quantities of the following copolymerizable unsaturated monomers: 
     4 - 40% vinylidene chloride 
     5 - 20% acrylic ester such as methyl acrylate, octyl acrylate 
     5 - 40% vinyl ethers such as n-butyl vinyl ether, cetyl vinyl ether 
     5 - 20% maleic and fumaric esters such as diethyl maleate, di-2-ethylhexyl fumarate 
     5 - 40% acrylonitrile 
     3 - 8% ethylene 
     3 - 15% propylene 
     The vinyl resin may be selected from one or more of the following groups: 
     1. PVC homopolymer dispersion grade resins 
     2. PVC-PVA copolymer dispersion grade resins 
     3. PVC homopolymer extender grade resins 
     4. PVC-PVA copolymer extender grade resins. 
     Both PVC homopolymer and PVC-PVA copolymer dispersion grade resins can be used in PVC compositions for foam carpet backings. PVC-PVA copolymer dispersion grade resins are often used in carpet backings because these resins produce foams which fuse at lower temperatures and have better tensile strengths and percent elongations than foams produced from PVC homopolymer dispersion grade resins. 
     Often PVC homopolymer or PVC-PVA copolymer extender grade resins are blended with PVC homopolymer or PVC-PVA copolymer dispersion grade resins to reduce the cost of the plastisol. extender grade resins are also used to control viscosity of the plastisol as well as modify other physical properties. A ratio of 60-70 parts by weight of dispersion grade resin to 30-40 parts by weight of extender resin is suggested as the starting ratio in formulating PVC foam compositions. 
     Individual plasticizers or blends of plasticizers are used in foamable PVC compositions to impart flexibility to the finished foam. Plasticizers affect other physical properties of the foam as well as viscosity stability and low temperature fusing characteristics of the plastisol. Plasticizers are classified as either primary or secondary plasticizers depending on their effects on the resin base. For PVC foam it is important that the plasticizer produce a plastisol with the desired rheological properties. Depending on the density and quality of foam required, the plasticizer level may vary from 40 to 125 phr to vary the plastisol properties. A volatile diluent may be added to form an organosol which can aid in the cellular structure formation. Liquid plasticizers which are well known in the art and which are used in producing mechanically whipped or frothed foams, are classified according to the following combination of chemical composition and end use: 
     1. Phthalate plasticizers 
     2. Phosphate plasticizers 
     3. Low temperature plasticizers 
     4. High molecular weight plasticizers 
     5. Miscellaneous plasticizers 
     Phthalate plasticizers are monomeric, general purpose primary plasticizers. They are probably the most widely used group of plasticizers and are used in most applications except in those applications where low temperature or flame resistance properties are required. Useful phthalate plasticizers include di-2-ethylhexyl phthalate, diisooctyl phthalate, dialphanol (C 7  -C 9 ) phthalate, butylbenzyl phthalate, diisodecyl phthalate, dibutyl phthalate. Phosphate plasticizers are used in applications where flame retardance is important. Useful phosphate plasticizers include tritolyl phosphate, trixylyl phosphate, cresyl diphenyl phosphate, triisopropylated phenol phosphate, tributoxyethyl phosphate. Low temperature plasticizers include sebacates, adipates and azelates. These esters of aliphatic dibasic acids include di-2-ethylhexyl sebacate, di-butoxyethyl adipate, benzyloctyl adipate, dibenzyl sebacate, tetrabutyl thiodisuccinate. Other esters include polyesters such as poly (propylene sebacate), alcohol modified, acid modified, ADMEX 433, DRAPEX 7.7 (Argus Chem.), Elastex 37-R (Allied Chem.) Flexol R2H (Carbide), Kodaflex polyesters (Eastman Kodak), Paraplex G-25 (Rohm &amp; Haas). High molecular weight plasticizers are primarily polymeric materials such as Kodaflex NP-10 (Eastman Chem.), Morflex X-1080 (Chas. Pfizer), Plastolein 3702 (Emery). They are used in foam formulations where high temperature stability and solvent resistance are required. Epoxidized oils, even though they are not polymeric, are included in this group. Useful epoxidized oils include octyl epoxy stearate, epoxidized soybean oil, Harflex 2020 (Harchem), Monoplex S-70 (Rohm &amp; Haas), Nuodex V-50 epoxy tall oil ester. These oils have the high molecular weights required for high temperature stability and have better low temperature properties than polymerics. Miscellaneous plasticizers include chlorinated paraffins, dipropylene glycol dibenzoate, long chain hydrocarbons, ethylene glycol monobutyl ether laurate, tricyclohexyl citrate, diisooctyl mono isodecyl trimellitate. This group also includes plasticizer blends which are prepared for specific applications by combining the properties of several plasticizers. 
     Non-solvating plasticizers tend to lower viscosity of the plastisol, whereas solving plasticizers lower the fusion temperature of the plastisol. A starting ratio of about 60 parts by weight of a non-solvating plasticizer to about 20 parts by weight of a solvating plasticizer is suggested. The ultimate ratio will depend on the plasticizers selected. 
     Since the plasticizer is the continuous phase in the plastisol compound, it is of primary concern in the selection of the silicone surfactant frothing agent. 
     Selection of the silicone surfactant frothing agent depends on the resin as well as the plasticizer in the plastisol. Often efficiency of the silicone surfactant can be improved by using a blend of solvating and non-solvating plasticizers in the plastisol. These frothing agents are well known in the art. Exemplary of the silicone surfactant frothing agents are copolymers prepared by the cohydrolysis of (CH 3 ) 3  SiX and/or Q(CH 3 ) 2  SiX with SiX 4 , wherein X is a hydrolyzable radical such as a halogen (chlorine, fluorine, bromine) or any alkoxy (methoxy, ethoxy, propoxy, butoxy, etc.) radical, employing, of course, such proportions as are necessary to obtain the desired SiO 2  to total (CH 3 ) 3  Si and Q(CH 3 ) 2  Si ratio of 1:0.6 to 1:1.2. Alternatively, copolymers can be prepared, for example, by reacting (CH 3 ) 3  SiCl,(CH 3 ) 3  SiOC 2  H 5  or (CH 3 ) 3  SiOSi(CH 3 ) 3  with an acidic silica sol. This method is fully described in U.S. Pat. No. 2,676,182, the disclosure of said patent being incorporated herein by reference. 
     A particularly useful means for preparing modified copolymers containing both (CH 3 ) 3  SiO 1/2  and Q(CH 3 ) 2  SiO 1/2  units involves cohydrolyzing a mixture of (CH 3 ) 3  SiX and H(CH 3 ) 2  SiX with SiX 4  and then coupling the desired solubilizing group Q to the copolymer by reacting the hydrogen on the silicon atom with the unsaturated group of a compound which also contains the desired solubilizing group. This type of reaction is well known to those skilled in the art. The purpose of the solubilizing group in the radical Q is to make the copolymer compatible with plastisols which it might not be compatible with otherwise. Any solubilizing group can be present in the copolymers of this invention, the particular plastisol in which the copolymer is being used determines the choice of solubilizing group. Examples of solubilizing groups which can be present in the Q radical include carboxyl, ester, amide, amino, mercapto, halohydrocarbon, nitrile, nitro, carbonyl and higher hydrocarbon groups. 
     The essential characteristics of the silicone surfactants defined above are the siloxane units present in the copolymer surfactant, the ratio of these units and the compatibility of the surfactant with the plastisol. By being &#34;compatible&#34;, it is meant that the surfactant is partially soluble and/or dispersible in the plastisol. Compatibility of the surfactant in the plastisol can be controlled in several ways. For example, one can choose a surfactant having the desired compatibility. Compatibility can be controlled by altering the Q radical. Still another alternative is to select a plasticizer for use in the plastisol which gives the desired degree of compatibility. It can be seen from the foregoing illustrations that silicone surfactants provide a maximum amount of flexibility which permits tailoring the surfactants and foamable compositions produced with the surfactants to meet specific specifications rather than vice versa. 
     The amount of surfactant used need only be sufficient to produce the desired foam density and will vary depending on the application. The amount of surfactant can vary from about 1 to about 5 phr of resin but this amount will depend on the resin and plasticizer selection as well as the desired foam density. 
     Since PVC polymers change color and harden on prolonged exposure to heat and light, conventional PVC heat and light stabilizers are used in foamable PVC compositions. From about 1 to about 5 phr of one or more of these PVC stabilizers may be added to the PVC foam composition. Chelated and unchelated metallic (barium, calcium, cadmium, zinc, magnesium) soaps and phenates, basic lead carbonate, tribasic lead sulfate, dibasic lead phosphites, organotins, may be used as stabilizers. 
     Fillers and pigments may also be used in PVC foam compositions. Fillers are used to reduce cost and pigments are used to add color to vinyl plastisol foams. The quantity of fillers may vary from about 10 to about 50 phr. When used, the quantity of pigments may vary from about 1 to about 2 phr. 
     Useful fillers include the most frequently used natural and precipitated calcium carbonates. Also calcined clays, talcs, barytes, aluminum oxides, calcium silicates, asbestos, diatomaceous earth, water ground mica, carbon and graphite, titanium dioxide may be used. PVC foam for furniture, automobiles, trains, planes, textiles, floorings, and carpet backing may be white, black, or colored. To obtain various colors, pigments such as benzidine yellow, chrome oxide green, Watchung Red (Pigment Red 48), phthalocyanine blue (Pigment Blue 15) may be used. 
     For the purposes of this invention, the term &#34;frothing agent&#34; is used to describe those silicone surfactants which actually foam the plastisol under mechanical agitation. The term &#34;frothing aid&#34; is used to describe those products which, although not being effective frothing agents by themselves, do increase the frothing activity of the silicone surfactants. 
     The frothing aid is used to extend the silicone surfactant frothing agent. From about 5.0 phr to about 10 phr of frothing aid is added to the foam composition. Useful oleophilic frothing aids include one or a mixture of the free acids of simple and complex organic phosphate mono and diesters and phosphites; organic nitrogen compounds such as amines, aminoamides, alkanolamides, imidazolines, quaternaries, and nitrogen-sulfur compounds, simple and complex organic borate esters such as 2-ethyl-hexyl borate, tri-hexylene glycol biborate, and tricresyl borates. Phosphate ester surfactants include those described in Krupin, &#34;Phosphate Ester Surfactants -- Newer Uses&#34;; Soap &amp; Chemical Specialities, p. 86, May, 1969, which is incorporated by reference herein, may be used. 
     Examples of frothing aids include: 
     1. Free acids of simple and complex organic phosphate mono and diesters - ##EQU1## R = C 8  - C 20 , or alkylphenyl or other aromatic. R may be alkoxylated (ethoxy, propoxy, butoxy). 
      Dicaprylacid phosphate, monolaurylacid phosphate, di (ethoxylated nonyl phenyl) phosphate, dioleyl acid phosphate, distearyl acid phosphate, chlorophenol acid phosphate, fluorocarbon and fluorohydrocarbon acid phosphates (e.g., from pentadecafluorooctyl alcohol). 
     2. Phosphites -- Organic acid phosphites such as didecyl hydrogen phosphite, dilauryl hydrogen phosphite, dioleyl hydrogen phosphite, di (2-ethylhexyl) hydrogen phosphite, diphenyl hydrogen phosphite, dioctadecyl hydrogen phosphite, decylphenyl hydrogen phosphite, lauryl dihydrogen phosphite, pentaerythritol hydrogen phosphite, bisphenol A hydrogen phosphite, thiophenol dihydrogen phosphite, dilauryldithio hyrogen phosphite, dinonylphenyl hydrogen phosphite, diallyl hydrogen phosphite, bromophenol hydrogen phosphite. 
     3. Amines -- Primary, secondary, and tertiary amines. RNH 2 , R 2  NH, R 3  N. R may be aliphatic (saturated or unsaturated), alicyclic, aromatic, or heterocyclic. Caprylamine, laurylamine, stearylamine, oleylamine, dilaurylamine, (cyclohexylmethyl) amine, aniline, 2-ethylhexylamine, t-alkyl primary amines (t-C 12  H 25  NH 2 , t-C 22  H 45  NH 2 ), trioctylamine, rosin amine, aminophenol, benzylamine, alkoxylated amines, N-alkyl trimethylene diamines from oleic or adipic acids, hydrogenated tallow amine, di-soya amine, N-coco morpholine, N-lauroyl ethylenediamine, benzylidenecyclohexylamine, N-aliphatic polyamines, perfluorocyclohexyl (C 6  F 11 ) amines. 
     4. Aminoamides -- Prepared from polyamines (diethylene triamine, triethylene tetramine, tetraethylene pentamine, aminoethylethanolamine) and fatty acids (caprylic, lauric, stearic, behenic, oleic, ricinoleic, linoleic). They may be polyoxyethylated, polypropoxylated, butoxylated. 
     5. Alkanolamides -- These range from amber liquids to waxy solids. They are prepared from mono and dialkanolamines and fatty acids; for example, ethanolamine, diethanolamine, mono and diisopropanolamine, phenyl ethanolamine, tetrahydroxyethyl ethylenediamine, 1-(2-aminoethylamine)-2 propanol condensed in 1:1 ratio and 2:1 ratio alkanolamine to fatty acid or ester (saturated or unsaturated) such as caprylic, lauric, stearic, behenic, oleic, palmitoleic, erucic, eleostearic, linoleic, linolenic, stearolic, ricinoleic, liconic, 2-ethylhexanoic. 
     6. Imidazolines -- Oleic hydroxyethyl imidazoline, tall oil hydroxyethyl imidazoline, coco hydroxyethyl imidazoline, imidazolines from the constituents listed under aminoamides, brominated tall oil hydroxyethyl imidazoline, 1-hydroxyethyl, 2 hepta-decadienyl imidazoline, 2-myristal-1 (ethyl beta oxipropanoic) imidazoline. 
     7. Quaternaries -- Oil Dispersible types. Polyethoxylated (or propolylated) fatty quaternary salts, octyl trimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride, octadecenyl and octadecadienyl, di and trimethyl ammonium chloride, dicoco dimethyl ammonium chloride, stearyl dimethyl benzyl ammonium chloride, ditallow dimethyl ammonium bromide, ditallow dimethyl ammonium methyl sulfate, dilauryl imidazolinium methosulfate, oleyl pyridinium chloride, hexadecyl trimethyl ammonium stearate. 
     8. Nitrogen-sulfur compounds -- Lubrizol L 40209 (an amine neutralized petroleum sulfonate -- 2.8% sulfur, 1.2% nitrogen), Conco AAS Special -- triethanolamine neutralized dodecylbenzenesulfonate, benzenedisulfonamide, dialkylaminoalkyl mercaptan R 2  N(CH 2 ) n  SH. 
     9. simple and complex organic borate esters-2-ethylhexyl borate, trihexylene glycol biborate, tri-m,p-cresyl borate, 2-(beta-dimethylaminoethoxy)-4-methyl-1,3,2-dioxaborinane, tri-n-butyl borate, triisopropanolamine borate, 2,6-di-tert-butyl-4-methylphenyl-di-n-butyl borate, lithium hexylene glycol monoborate, borate of N-hydroxyethyl-N-sec octadecyl piperazine, complexes such as of tetraphenylborate iridium, polymeric borate esters from polyols and boron trihalides, glycerine borate, brominated borate esters, fluorinated borate esters from fluorohydrocarbon alcohols. 
     The frothing aid may be a mixture of several frothing aids. Useful frothing aid mixtures include a mixture of a free acid of tridecyl alcohol phosphate ester, a trihexyleneglycol biborate, and an alkanolamide of coconut fatty acids and diethanolamine; a mixture of a free acid of an oleyl alcohol ethoxylate phosphate ester, a 2-ethylhexyl borate, and an organic nitrogen-sulfur compound; a mixture of a 2-ethylhexyl borate, a free acid of tridecyl alcohol phosphate ester, and an alkanolamide of coconut fatty acids and diethanolamine; or a mixture of a free acid of tridecyl alcohol phosphate ester, a trihexyleneglycol biborate, and a tertiary (C 12  -C 14 ) primary amine. 
     A simple screening test may be used to determine whether or not a given compound or mixture of compounds will foam a vinyl resin plastisol. If a compound does not foam the plasticizer, it will not foam a plastisol prepared with the plasticizer. Since other plastisol components such as the vinyl resins, other plasticizers, stabilizers, fillers and pigments present in the foam composition will also influence the foaming ability of frothing agents and frothing aids, it is possible that a compound or a mixture of compounds which passes a simple plasticizer foaming screening test (which may be as simple as shaking 2.5 g of potential frothing agent or frothing aid in 50 g of plasticizer for 10 sec in a bottle) may fail in the actual plastisol frothing test. However, this simple plasticizer screening test does not make it possible to discover that certain organic phosphorus, boron, nitrogen compounds and mixtures of these compounds will increase the foaming activity of the silicone frothing agents with the result that less silicone frothing agent is required to produce the same froth and fused foam densities. 
     The following plastisol formulation may be used to evaluate the frothing aids of this invention: 
     
         Vinyl resin,dispersion grade                                              
                        60.0     parts                                    
Fast fusing homopolymer extender PVC resin                                
                        40.0     parts                                    
No. 10 Whiting          20.0     parts                                    
Plasticizer             75.0-85.0                                         
                                 parts*                                   
Silicone frothing agent 2.0-4.0  parts                                    
Vinyl resin stabilizer  1.0      parts                                    
Frothing aid            5.0-10.0 parts                                    
 *Normally in this typical carpet backing plastisol for PVC foam          
 production, 85.0 parts of plasticizer is used. However, when a frothing  
 aid is used, the plasticizer content can be reduced by an amount equal to
 the amount of frothing aid added.                                        
 
    
     In evaluation of the frothing aid, approximately 624 g of plastisol containing the frothing agent and frothing aid is whipped for 5 minutes using a Model N-50 Hobart Mixer with wire whip, at Speed No. 2 (the most effective speed for lowest density froth and fused foam) to froth the plastisol. Froth density is determined using 9 oz paper cups. A Brookfield Synchro-Lectric Viscometer, Model LVF, Spindle No. 4, Speed 12, is used to measure froth viscosity. The resulting vinyl resin plastisol froths are then fused in aluminum trays at 280°F in a forced air oven for 10 minutes to obtain approximately 6 × 23/4 × 1/4 inch PVC fused foams. Foams are weighed and densities calculated. Surface characteristics, cell structure, odor, and color are also noted. 
     Mixing equipment commonly used to froth or foam vinyl plastisols mechanically include the Oakes foamer (E. T. Oakes Corporation, Islip, New York) and the Texacote foamer (Textile Rubber and Chemical Company, Dalton, Georgia). Foam can be produced continuously by feeding the foam composition into the mixing chamber of the Oakes foamer at a constant rate using a positive displacement variable speed pump. The mixing chamber employs sets of teeth or pins both on the rotating and stationary meshing units. The small clearance between the two units produces a high rate of shear which facilitates dispersion of an air stream into the foam composition. 
     The resulting foams are heated at about 250° to about 320°F to fuse the foam. Some foams expand during the fusion steps in these tests when frothing aids are used in combination with silicone surfactants. This is an important feature because more foam can be produced from an equal weight of plastisol. 
    
    
     For a fuller understanding of the nature and objects of this invention, reference may be made to the following examples. These examples are given merely to illustrate the invention and are not to be construed in a limiting sense. All parts, proportions and quantities are by weight unless otherwise indicated. The terms g, 1, °C, °F, lb, ft 3 , phr, cps are used to indicate grams, liters, degrees Centigrade, degrees Fahrenheit, pounds, cubic feet, parts per hundred parts resin, centipoises respectively, in these examples. 
     EXAMPLE I 
     The various compounds shown in Table I are evaluated as frothing aids to extend the silicone surfactant frothing agent in the following foamable plastisol formulation: 
     
                                  Concentration                                    
Component                phr                                              
______________________________________                                    
Vinyl resin,dispersion grade                                              
                         60.0                                             
Fast fusing homopolymer extender PVC resin                                
                         40.0                                             
No. 10 Whiting           20.0                                             
Plasticizer              75.0-85.0                                        
Silicone frothing agent  2.0-4.0                                          
Vinyl resin stabilizer    1.0                                             
Frothing aid              5.0- 10.0                                       
______________________________________                                    
 
    
     The plasticizer is Eastman CB-A (a blend of butyl benzyl phthalate, isobutyrate viscosity depressant and butyl octyl phthalate). Normally in this typical carpet backing plastisol for PVC foam production, 85.0 phr of plasticizer are used. However, when a frothing aid or a mixture of frothing aids is used, the plasticizer content may be reduced by an amount equal to the amount of the frothing aid added. The silicone surfactant frothing agent used in these tests is General Electric SS4255, a 50% solvent solution of silicone surfactant. 
     The quantities of Phosphorous Compound, Boron Compound and Other Compounds given in Table I are mixed to obtain frothing aid mixtures as clear, stable, viscous liquids. Exothermic reactions may occur when Phosphorous Compounds, e.g., organic phosphate esters are mixed with Nitrogen Compounds and reaction temperatures as high as 85°C may be obtained during mixing. When Boron Compounds, e.g., borate esters are added to these mixtures, the resulting mixtures are heated to 95° to 100°C. All mixtures are heated to 95° to 100°C. 
     Each frothing aid or frothing aid mixture is evaluated by mechanically whipping approximately 624 g of plastisol containing silicone surfactant and frothing aid for 5 minutes using a Model N-50 Hobart Mixer with wire whip, at Speed No. 2 (the most effective speed for lowest density froth and fused foam). Froth density is measured in a 9 oz paper cup. A Brookfield Synchro-Lectric Viscometer, Model LVF, Spindle No. 4, Speed 12, is used to measure froth viscosity. The resulting foamed vinyl resin plastisol is fused in an aluminum tray at 280°F in a forced air oven for 10 minutes to obtain approximately 6 × 23/4 × 1/4 inch sample of PVC fused foam. Each fused foam sample is weighed and its density calculated. Surface characteristics, cell structure, odor, and the color of each foam sample are noted. 
     Controls used for determining effectiveness of frothing aids are the froth densities and fused foam densities obtained with 4.0, 3.0 and 2.0 phr silicone frothing agent in the plastisol formulation without a frothing aid. Any frothing aid or mixture of frothing aids, which produces lower froth densities and fused foam densities than those obtained with 2.0 phr frothing agent in the controls, is considered to be an improved product of this invention. 
     
                                           TABLE I                                 
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
          Frothing Aid Composition                                        
Foam phr    %     %                Brookfield                             
                                         Froth                            
                                             Fused Foam                   
Test Frothing                                                             
          Phosphorus                                                      
                  Boron     %      Viscosity                              
                                         Density                          
                                             Density                      
Number                                                                    
     Aid   Compound                                                       
                  Compound                                                
                        Other Compounds                                   
                                   Froth cps                              
                                         g/l lb/ft.sup.3                  
__________________________________________________________________________
 1   10.0 25 CROD. N3                                                     
                  50 Q  25 L40209  17250 555 20.4                         
 2 8.0                                                                    
     25 CROD. N3                                                          
          50 Q    25 L40209                                               
                        14500      575   22.9                             
 3   10.0 25 CROD. N3                                                     
                  50 Q  225 VARIQUAT L200                                 
                                   21750 580 25.2                         
/ 4  10.0 25 RE960                                                        
                  25 Q  50 L40209  22500 580 26.3                         
 5   10.0 50 CROD. N3                                                     
                  50 Q             21500 550 26.5                         
 6   8.0  50 CROD. N3                                                     
                  50 Q             21750 550 27.1                         
 7   6.0  50 CROD. N3                                                     
                  50 Q             24750 570 27.3                         
 8   8.0  25 CROD. N3                                                     
                  25 Q  50 L40209  17000 590 27.9                         
 9   10.0         50 Q  50 L40209  16500 575 28.2                         
10   10.0 25 ACT. T                                                       
                  50 Q  25 L40209  23000 600 28.2                         
11   6.0  25 RE 960                                                       
                  25 Q  50 L40209  25500 580 28.6                         
12   6.0  25 CROD. N3                                                     
                  50 Q  25 L40209  15750 595 28.6                         
13   4.0  50 CROD. N3   50 L40209  24250 600 28.6                         
14   8.0  25 ACT. T                                                       
                  50 Q  25 L40209  24500 615 28.6                         
15   6.0                100 L40209 28000 585 28.7                         
16   4.0  50 CROD. N3                                                     
                  50 Q             24500 585 28.8                         
17   4.0          50 Q  50 L40209  20000 610 28.9                         
18   8.0                100 L40209 23250 585 29.0                         
19   6.0  25 ACT. T                                                       
                  50 Q  25 L40209  24500 620 29.1                         
20   8.0  25 RE960                                                        
                  25 Q  50 L40209  24500 575 29.4                         
21   6.0  50 CROD. N3   50 L40209  23250 600 29.4                         
22   6.0          50 Q  50 L40209  16500 595 29.5                         
23   4.0  25 CROD. N3                                                     
                  50 Q  25 L40209  18500 595 29.6                         
24   8.0  50 CROD. N3   50 L40209  23000 605 29.6                         
25   10.0 50 CROD. N3   50 L40209  26500 610 29.6                         
26   4.0                100 L40209 26000 600 29.8                         
27   6.0  25 CROD. N3                                                     
                  25 Q  50 L40209  20000 595 30.0                         
28   4.0  25 CROD. N3                                                     
                  25 Q  50 L40209  26000 605 30.1                         
29   10.0               100 L40209  25000                                 
                                         580 30.4                         
30   8.0          50 Q  50 L40209  16500 580 30.5                         
31   8.0  25 CROD. N3                                                     
                  50 Q  25 VARIQUAT L200                                  
                                   20000 600 30.6                         
32   10.0 25 CROD. N3                                                     
                  25 Q  50 L40209  20750 595 31.4                         
33   4.0  25 CROD. N3                                                     
                  50 Q  25 VARIQUAT L200                                  
                                   26500 610 31.8                         
34   CONTROL      2.0 phr SS 4255  23500 620 32.1                         
35   CONTROL      3.0 phr SS 4255  15000 585 27.6                         
36   CONTROL      4.0 phr SS 4255  18000 490 25.2                         
__________________________________________________________________________
 
    
     EXAMPLE II 
     The procedure of Example I is repeated with the exceptions that the silicone surfactant frothing agent used in the plastisol formulation is Dow Corning 1250, a 50% xylene solution of silicone surfactant and the plasticzer is butyl ethylhexyl phthalate. Results of these tests are shown in Tables II through VIII inclusive. 
     
                                           TABLE II                                
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
          Frothing Aid Composition                                        
            %                                                             
Foam phr  Nitrogen-                                                       
                   %    %       %   Froth                                 
                                         Froth                            
                                             Fused Foam                   
Test Frothing                                                             
          Sulfur Phosphorus                                               
                        Boron Nitrogen                                    
                                    Viscosity                             
                                         Density                          
                                             Density                      
Number                                                                    
     Aid  Compound                                                        
                  Compound                                                
                        Compound                                          
                              Compound                                    
                                    cps  g/l lb/ft.sup.3                  
__________________________________________________________________________
37   10.0        50 ACT. T                                                
                        25 B7 25 Z  19000                                 
                                         525 22.3                         
38   10.0        25 ACT. T                                                
                        25 B7 25 81R                                      
                                    22500                                 
                                         510 22.9                         
                 25 W                                                     
39   10.0        50 ACT. T                                                
                        25 B7 25 Y  21250                                 
                                         510 23.3                         
40   10.0        37.5 ACT. T                                              
                        25 B7 37.5 2C                                     
                                    28000                                 
                                         500 23.7                         
41   10.0 10 L40209                                                       
                 40 ACT. T                                                
                        25 B7 25 Y  20000                                 
                                         520 23.7                         
42   10.0        25 ACT. T                                                
                        25 B7 25 2C 20750                                 
                                         510 24.0                         
                 25 W                                                     
43    7.5 10 L40209                                                       
                 40 ACT. T                                                
                        25 B7 25 Y  20000                                 
                                         525 24.1                         
44   10.0 25 AAS 50 ACT. T                                                
                        25 B7       26500                                 
                                         535 24.2                         
45   10.0 25 L40209                                                       
                 50 ACT. T                                                
                        25 B7       25500                                 
                                         545 24.2                         
46   10.0        50 ACT. T                                                
                        25 Q  25 Y  21010                                 
                                         495 24.3                         
47    7.5        50 ACT. T                                                
                        25 Q  25 Y  23000                                 
                                         500 24.3                         
48   10.0        25 ACT. T                                                
                        25 B7 25 TOA                                      
                                    24000                                 
                                         525 24.3                         
                 25 W                                                     
49    5.0        50 ACT. T                                                
                        25 B7 25 Y  22750                                 
                                         530 24.4                         
50    7.5        50 ACT. T                                                
                        25 B7 25 Z  20250                                 
                                         535 24.4                         
51   10.0        37.5 ACT. T                                              
                        25 B7 37.5 2HT                                    
                                    24750                                 
                                         530 24.7                         
52   10.0        50 ACT. T                                                
                        25 B7 25 2HT(A)                                   
                                    25250                                 
                                         530 24.9                         
53   10.0 12.5 L40209                                                     
                 50 ACT. T                                                
                        25 B7 12.5 RD                                     
                                    22000                                 
                                         535 25.0                         
54   10.0 25 L40209                                                       
                 50 ACT. T                                                
                        25 B7       23750                                 
                                         540 25.0                         
55   10.0        25 ACT. T                                                
                        25 B7 25 JMT                                      
                                    21000                                 
                                         510 25.2                         
                 25 W                                                     
56   10.0 25 L40209                                                       
                 12.5 ACT. T                                              
                        50 B7       18000                                 
                                         550 25.2                         
                 12.5 RE960                                               
57   CONTROL     4.0 phr DOW CORNING 1250                                 
                                    24750                                 
                                         480 25.5                         
__________________________________________________________________________
 
    
     
                                           TABLE III                               
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
           %                                                              
Foam                                                                      
     phr Nitrogen-                                                        
                   %      %     %      Froth                              
                                            Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulfur  Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                  Density                 
Number                                                                    
     Aid Compound                                                         
                  Compound                                                
                         Compound                                         
                               Compound                                   
                                       cps  g/l   lb/ft.sup.3             
__________________________________________________________________________
58  5.0          50 ACT. T                                                
                         25 Q  25 Y   123500                              
                                            520  25.5                     
59  5.0  25 L40209                                                        
                 50 ACT. T                                                
                         25 B7        22000 550  25.5                     
60  5.0  25 L40209                                                        
                 12.5 ACT. T                                              
                         50 B7        22500 560  25.5                     
                 12.5 RE960                                               
61  5.0          50 ACT. T                                                
                         25 B7 25 Z   23750 535  25.6                     
62  7.5  25 AAS  50 ACT. T                                                
                         25 B7        22000 550  25.6                     
63  7.5  25 L 40209                                                       
                 50 ACT. T                                                
                         25 B7        22750 545  25.7                     
64  10.0         50 ACT. T                                                
                         12.5 B7                                          
                               25 81R 20000 535  25.8                     
                         12.5 Q                                           
65  10.0         25 ACT. T                                                
                         50 Q  25 Y   18750 505  25.9                     
66  7.5  12.5 L40209                                                      
                 50 ACT. T                                                
                         25 B7 12.5 RD                                    
                                      22000 535  25.9                     
67  10.0 10 L40209                                                        
                 30 ACT. T                                                
                         60 B7        27000 550  25.9                     
68  7.5          50 ACT. T                                                
                         25 B7 25 Y   20500 525  26.0                     
69  5.0  25 L40209                                                        
                 25 RE960                                                 
                         50 B7        21750 575  26.1                     
70  10.0 25 AAS  50 ACT. T     25 81R 24750 540  26.2                     
71  7.5          50 ACT. T                                                
                         25 B7 25 X   21000 535  26.2                     
72  5.0          37.5 ACT. T                                              
                         25 B7 37.5 2C                                    
                                      25500 545  26.3                     
73  10.0         37.5 ACT. T                                              
                         25 B7 37.5 DMCD                                  
                                      22500 520  26.3                     
74  5.0  25 L40209                                                        
                 25 ACT. T                                                
                         50 B7        22250 550  26.3                     
75  10.0         50 ACT. T                                                
                         12.5 B7                                          
                               37.5 TOA                                   
                                      22500 535  26.4                     
76  10.0 10 L40209                                                        
                 25 ACT. T                                                
                         25 B7 40 81R 20000 535  26.4                     
__________________________________________________________________________
 
    
     
                                           TABLE IV                                
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
           %                                                              
Froth                                                                     
     phr Nitrogen-                                                        
                   %     %     %      Froth Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulphur Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                 Density                  
Number                                                                    
     Aid Compound                                                         
                 Compound                                                 
                         Compound                                         
                               Compound                                   
                                      cps   g/l  lb/ft.sup.3              
__________________________________________________________________________
77  7.5          550 ACT. T                                               
                         25 B7 25 VO  19500 550  26.5                     
78  7.5          50 ACT. T                                                
                         25 B1 25 K202P                                   
                                      25750 525  26.6                     
79  10.0         50 ACT. T                                                
                         25 B7 25 X   20750 525  26.6                     
80  7.5          50 ACT. T                                                
                         25 B7 12.5 RD                                    
                                      23500 540  26.6                     
                               12.5 81R                                   
81  10.0         50 ACT. T                                                
                         25 B7 12.5 RD                                    
                                      24000 540  26.6                     
                               12.5 81R                                   
82  7.5  25 AAS  50 ACT. T     25 81R 23750 550  26.6                     
83  7.5          50 ACT. T                                                
                         25 B7 25 Y   20000 530  26.7                     
84  10.0         25 ACT. T                                                
                         50 B7        16000 540  26.7                     
                 25 W                                                     
85  7.5  10 L40209                                                        
                 25 ACT. T                                                
                         25 B7 40 81R 20000 540  26.7                     
86  10.0 25 L40209                                                        
                 12.5 ACT. T   50 2C  19000 545  26.7                     
                 12.5 W -87                                               
                         10.0         50 ACT.                             
                                            25 B7                         
                                                 25 VT  19950 530 26.8    
88  10.0 25 L40209                                                        
                 25 ACT. T                                                
                         50 B7        18250 545  26.8                     
                 25 ACT. T                                                
89  10.0         25 ACT. T     50 2S  18000 550  26.8                     
                 25 W                                                     
90  5.0          25 ACT. T                                                
                         50 B7        18350 555  26.8                     
                 25 W                                                     
91  7.5  50 AAS          25 B7 25 81R 17000 595  26.8                     
92  5.0          37.5 ACT. T                                              
                         25 B7 37.5 2HT                                   
                                      22500 550  26.9                     
93  10.0         50 ACT. T                                                
                         25 B7 25 Z-1 21250 530  27.0                     
94  5.0          50 ACT. T                                                
                         25 B7 25 Z-1 23500 540  27.0                     
95  5.0          25 ACT. T                                                
                         50 Q  25 Y   19000 540  27.1                     
96  10.0         37.5 ACT. T                                              
                         25 B7 37.5 B100                                  
                                      27250 550  27.1                     
__________________________________________________________________________
 
    
     
                                           TABLE V                                 
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
          %                                                               
Foam                                                                      
     phr Nitrogen-                                                        
                   %     %     %      Froth Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulfur  Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                 Density                  
Number                                                                    
     Aid Compound                                                         
                 Compound                                                 
                         Compound                                         
                               Compound                                   
                                      cps   g/l  lb/ft.sup.3              
__________________________________________________________________________
97  10.0         50 ACT. T                                                
                         25 B7 25 K202P                                   
                                      23000 525  27.3                     
98  5.0  12.5 L40209                                                      
                 50 ACT. T                                                
                         25 B7 12.5 RD                                    
                                      24000 550  27.5                     
99  5.0          50 DPP  50 B7        24250 570  27.6                     
100 10.0 10 L40209                                                        
                 25 ACT. T                                                
                         50 B7 15 81R 20500 540  27.8                     
101 5.0  25 L40209                                                        
                 50 ACT. T                                                
                         25 B7        17500 550  27.8                     
102 5.0          50 ACT. T                                                
                         25 B7 25 VO  23000 560  27.8                     
103 7.5  10 L40209                                                        
                 30 ACT. T                                                
                         60 B7        25000 580  27.8                     
104 10.0         37.5 ACT. T                                              
                         25 B7 37.5 DMHTD                                 
                                      24250 535  27.9                     
105 7.5          50 ACT. T                                                
                         12.5 B7                                          
                               25 81R 19500 540  27.9                     
                         12.5 Q                                           
106 5.0  10 L40209                                                        
                 25 ACT. T                                                
                         25 B7 40 81R 22750 550  27.9                     
107 5.0          37.5 ACT. T                                              
                         25 B7 37.5 DMHTD                                 
                                      22750 560  27.9                     
108 5.0  25 L40209                                                        
                 12.5 ACT. T   50 2C  17000 560  28.2                     
                 12.5 W                                                   
109 5.0          25 ACT. T                                                
                         25 B7 25 2C  16000 545  28.3                     
                 25 W                                                     
110 10.0 25 L40209                                                        
                 12.5 RE960                                               
                         50 B7        22250 560  28.2                     
                 12.5 W                                                   
111 5.0  25 AAS  50 ACT. T     25 81R 27500 560  28.3                     
112 10.0                 50 B7 50 C   14000 570  28.3                     
__________________________________________________________________________
 
    
     
                                           TABLE VI                                
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
           %                                                              
Foam                                                                      
     phr Nitrogen-                                                        
                   %     %     %      Froth Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulfur  Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                 Density                  
Number                                                                    
     Aid Compound                                                         
                 Compound                                                 
                         Compound                                         
                               Compound                                   
                                      cps   g/l  lb/ft.sup.3              
__________________________________________________________________________
113 7.5          50 ACT. T                                                
                         25 B7 25 RD  23250 570  28.4                     
114 10.0 25 L40209                                                        
                 12.5 RE960                                               
                         50 B7        20000 590  28.4                     
                 12.5 CROD. N3                                            
115 5.0          25 ACT. T                                                
                         25 B7 25 TBA 22750 580  28.5                     
                 25 W                                                     
116 10.0         50 ACT. T                                                
                         25 B7 25 VO  19250 535  28.6                     
117 7.5  10 L40209                                                        
                 25 ACT. T                                                
                         50 B7 15 81R 18000 545  28.6                     
118 5.0                  50 B7 50 C   16500 575  28.6                     
119 5.0  25 L40209                                                        
                 12.5 RE960                                               
                         50 B7        24000 580  28.6                     
                 12.5 CROD. N3                                            
120 10.0 25 L40209                                                        
                 12.5 ACT. T   50S    21000 580  28.6                     
                 12.5 W                                                   
121 10.0 50 AAS          25 B7 25 81R 19000 595  28.6                     
122 10.0 25 L40209                                                        
                 25 ACT. T     50 2C  22750 525  28.7                     
123 7.5          50 ACT. T                                                
                         25 B7 25 VT  21000 535  28.7                     
124 5.0          25 ACT. T                                                
                         25 B7 25 TOA 25250 550  28.9                     
                 25 W                                                     
125 5.0          50 ACT. T                                                
                         25 B7 25 K202P                                   
                                      21000 550  28.9                     
126 10.0         50 DPP  50 B7        23500 555  29.0                     
__________________________________________________________________________
 
    
     
                                           TABLE VII                               
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
           %                                                              
Foam                                                                      
     phr Nitrogen-                                                        
                   %     %     %      Froth Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulfur  Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                 Density                  
Number                                                                    
     Aid Compound                                                         
                 Compound                                                 
                         Compound                                         
                               Compound                                   
                                      cps   g/l  lb/ft.sup.3              
__________________________________________________________________________
127 5.0  10 L40209                                                        
                 30 ACT. T                                                
                         60 B7        22250 580  29.0                     
128 5.0          25 ACT. T                                                
                         25 B7 25 JMT 18500 550  29.1                     
                 25 W                                                     
129 5.0          50 ACT. T                                                
                         25 B7 25 VT  24000 550  29.1                     
130 10.0         25 DPP  50 B7 25 C   17500 575  29.2                     
131 10.0 25 L40209                                                        
                 25 RE960                                                 
                         50 B7        18750 580  29.2                     
132 10.0         ACT. T  25 B7 25 TBA 24000 595  29.3                     
                 25 W                                                     
133 7.5  10 L40209                                                        
                 30 Z-2  60 B7        21100 600  29.3                     
134 5.0          50 ACT. T                                                
                         12.5 B7                                          
                               25 81R 22500 550  29.4                     
                         12.5Q                                            
135 10.0 10 L40209                                                        
                 30 Z-2  60 87        19250 595  29.4                     
136 5.0  25 L40209                                                        
                 25 ACT. T     50 2HT(A)                                  
                                      17500 580  29.6                     
137 10.0 25 L40209                                                        
                 25 CROD. N3                                              
                         50 B7        21500 580  29.6                     
138 5.0          50 ACT. T                                                
                         25 B7 25 2HT (A)                                 
                                      18500 565  29.7                     
139 5.0  25 DPP  50 B7   25 C  18500  585   29.8                          
140      CONTROL 3.0 phr DOW CORNING 1250 SILICONE                        
                                      21000 600  29.7                     
__________________________________________________________________________
 
    
     
                                           TABLE VIII                              
__________________________________________________________________________
MECHANICAL FOAM TESTS WITH PLASTISOL CONTAINING 2.0 phr SILICONE          
SURFACTANT                                                                
         Frothing Aid Composition                                         
          %                                                               
Foam                                                                      
     phr Nitrogen-                                                        
                   %     %     %      Froth Froth                         
                                                 Fused Foam               
Test                                                                      
    Frothing                                                              
         Sulfur  Phosphorus                                               
                         Boron Nitrogen                                   
                                      Viscosity                           
                                            Density                       
                                                 Density                  
Number                                                                    
     Aid Compound                                                         
                 Compound                                                 
                         Compound                                         
                               Compound                                   
                                       cps  g/l  lb/ft.sup.3              
__________________________________________________________________________
141 10.0 10 L40209                                                        
                 30 CROD. N3                                              
                         60 B7        18500 600  29.8                     
142 5.0          37.5 ACT. T                                              
                         25 B7 37.5 B100                                  
                                      23000 575  30.1                     
143 7.5  10 L40209                                                        
                 30 CROD. N3                                              
                         60 B7        20000 590  30.1                     
144 5.0          50 ACT. T                                                
                         12.5 B7                                          
                               37.5 TOA                                   
                                      25500 545  30.2                     
145 5.0  50 AAS          25 B7 25 81R 20000 590  30.2                     
146 10.0 25 L40209                                                        
                 25 DPP  50 B7        13000 580  30.4                     
147 5.0  25 L40209                                                        
                 12.5 RE960                                               
                         50 B7        22000 565  30.5                     
                 12.5 W                                                   
148 10.0         50 ACT. T                                                
                         25 B7 25 RD  22500 565  30.5                     
149 10.0 25 L40209                                                        
                 25 ACT. T     50 2HT(A)                                  
                                      15000 590  30.5                     
150 5.0  25 L40209                                                        
                 25 ACT. T     50 2C  19250 540  30.6                     
151 5.0  10 L40209                                                        
                 30 CROD. N3                                              
                         60 B7        21500 595  30.6                     
152 5.0  25 L40209                                                        
                 25 DPP  50 B7        18000 600  30.7                     
153 5.0          25 ACT. T                                                
                         25 B7 25 81R 21000 535  30.8                     
                 25 W                                                     
154      CONTROL 2.0 phr DOW CORNING 1250 SURFACTANT                      
                                      22000 580  30.8                     
__________________________________________________________________________
 
    
     
         KEY TO TABLES I THROUGH VIII                                              
__________________________________________________________________________
ACT. T.   Arthur C. Trask Co. ACTROFOS T, acid form tridecyl alcohol      
          phosphate ester.                                                
AAS       Continental Chem. CONCO AAS Special. Triethanelamine Neut.      
          dodecylbenzene sulfonate.                                       
B7        U.S. Borax BORESTER 7, trihexyleneglycol biborate.              
B100      Armour ARQUAD B100, 50% soln. coco dimethyl benzyl ammonium     
          chloride.                                                       
C         Armour ARMEEN C- cocoamine.                                     
2C        Armour ARMEEN 2C, dicocoamine.                                  
CROD. N3  Croda Inc. CRODAFOS N3, acid form phosphated oleyl ether.       
DMCD      Armour ARMEEN DMCD, lauryl-myristyl tert. amine.                
DMHTD     Armour ARMEEN DMHTD, palmityl-stearyl tert. amine.              
DC 1250   Dow Corning 1250 Silicone Surfactant - Dow Corning.             
DPP       EASTMAN diphenyl phosphite.                                     
2HT       Armour ARQUAD 2HT, 75% di(hexadecyl-octadecyl) quaternary       
          ammonium chloride.                                              
2HT (A)   Armour ARMEEN 2HT, di(hydrogenated tallow) amine.               
JMT       Rohm and Haas PRIMENE JM-T, tert. (C.sub.18 -C.sub.22) primary  
          amine.                                                          
K202P     Varney Chem. VARONIC K202P, propoxylated cocoamine.             
L 40209   Lubrizol Corp. experimental organic nitrogen-sulphur compound.  
Q         2-ethylhexyl borate.                                            
RD        Hercules ROSIN AMINE D.                                         
RE960     GAF GAFAC RE960, acid organic phosphate.                        
81R       Rohm and Haas PRIMENE 81R, tert. (C.sub.12 -C.sub.14) primary   
          amine.                                                          
S         Armour ARMEEN S, soyamine.                                      
2S        Armour ARMEEN 2S, disoyamine.                                   
SS4255    50% solvent solution of silicone surfactant - General           
          Electric.                                                       
TBA       Rohm and Haas tert. butyl primary amine.                        
TOA       Rohm and Haas tert. octyl primary amine.                        
VARIQUAT L200                                                             
          Soya trimethyl ammonium chloride - Northern Petro Chemical.     
VO        Varney Chem. VARINE O, oleic imidazoline.                       
VT        Varney Chem. VARINE T, tall oil imidazoline.                    
W         Free acid phosphate ester of C.sub.8.sub.-10 alcohols.          
X         Oleic imidazoline.                                              
Y         Alkanolamide of coconut oil and diethanolamine.                 
Z         Aminoamide of oleic acid and aminoethylethanolamine.            
Z-1       Alkanolamide of coconut oil fatty acids and diethanolamine.     
Z-2       Free acid phosphate ester of polyoxypropylene derivative of     
          propylene glycol.                                               
__________________________________________________________________________
 
    
     EXAMPLE III 
     The procedure of Example II is repeated using 2.0 phr of Dow Corning 1250 as the frothing agent and the quantities of the frothing aid shown in the table below. The chemical nature of the components employed in these formulations are described in the Key to Tables I through VIII. 
     
         ______________________________________                                    
                                    Fused                                 
                 Froth     Froth    Foam                                  
                 Viscosity Density  Density                               
Test Formulation Contains                                                 
                  cps       g/l     lb/ft.sup.3                           
______________________________________                                    
 2.0 phr Dow Corning 1250                                                 
plus                                                                      
 5.0 phr Frothing aid Y                                                   
                 29,500    545      26.4                                  
 7.5 phr Frothing aid Y                                                   
                 28,000    540      25.9                                  
10.0 phr Frothing aid Y                                                   
                 27,500    540      27.9                                  
 2.0 phr Dow Corning 1250                                                 
plus                                                                      
 5.0 phr Frothing aid B7                                                  
                 19,750    540      29.2                                  
 7.5 phr Frothing aid B7                                                  
                 16,500    550      27.2                                  
10.0 phr Frothing aid B7                                                  
                 16,500    550      27.8                                  
 2.0 phr Dow Corning 1250                                                 
plus                                                                      
 5.0 phr Frothing aid ACT. T                                              
                 28,000    520      25.3                                  
 7.5 phr Frothing aid ACT. T                                              
                 28,000    520      24.0                                  
10.0 phr Frothing aid ACT. T                                              
                 26,250    520      24.0                                  
______________________________________                                    
 
    
     EXAMPLE IV 
     This example describes use of the Oakes continuous mixer to produce foams from PVC foam compositions. Five gallon samples of the test formulations given in the table below are prepared using a Cowles Dissolver. Test Formulations No. 1 and No. 2 are control formulations which do not contain a frothing aid, whereas Test Formulations No. 3 and No. 4 contain Frothing Aid No. 65B and Frothing Aid No. 83A, respectively. The composition of Frothing Aid No. 65B is 
     50% Q 
     25% lubrizol 40209 
     25% Crodafos N-3 
     and the composition of Frothing Aid No. 83A is 
     25% Borester 7 
     25% Actrafos T 
     25% w 
     25% primene 81-R. 
     The chemical nature of the components employed in these formulations are described in the Key to Tables I through VIII. 
     Each test formulation is fed into the Oakes Foamer until the minimum density froth without &#34;blowby&#34; is obtained. Blowby is defined as the inability of the Oakes Mixer to incorporate in the foam the volume of air being supplied to the mixer. Blowby manifests itself by pock marks in the surface of the foam as it exits from the nozzle or by spurting of foam from the nozzle. The froth is fed onto a moving fiber belt with a doctor blade to form 1/4 inch height pads. The froth pads are fused in an oven at 275°-280°F for 5 minutes. 
     
         TEST FORMULATIONS                                                         
Test Formulation   No. 1                                                  
                        No. 2                                             
                             No. 3                                        
                                  No. 4                                   
__________________________________________________________________________
Polyvinyl chloride copolymer                                              
                   60   60   60   60                                      
 dispersion resin                                                         
Intermediate molecular weight poly-                                       
                   40   40   40   40                                      
 vinyl chloride homopolymer extender                                      
 resin                                                                    
Butyl ethylhexyl phthalate                                                
                   85   85   75   75                                      
No. 10 Whiting     20   20   20   20                                      
PVC stabilizer     1    1    1    1                                       
Silicone frothing agent                                                   
                   2    4    2    2                                       
Frothing aid 65B   --   --   10   --                                      
Frothing aid 83A   --   --   --   10                                      
FROTH DENSITY (g/6 oz cup)                                                
                   --   79.8 71.6 78.8                                    
FOAM DENSITY (lb/ft.sup.3)                                                
                   --   20.7 20.7 20.5                                    
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     Test Formulation No. 1 is not satisfactory because excessive &#34;blowby&#34; cannot be eliminated by adjusting Oakes Foamer air flow, rotor speeds and pump feed rate. Test Formulations No. 2, No. 3 and No. 4 produce satisfactory foams in the Oakes Foamer. 
     While the invention has been described with reference to certain specific embodiments thereof, it is understood that it is not to be so limited since alterations and changes may be made therein which are within the full and intended scope of the appended claims.