COMPOSITIONS OF UNSATURATED POLYESTERS OR POLYESTERAMIDES AND EFFICIENT FLEXIBILIZERS THEREFOR

Abstract: Polyester and polyesteramide alkyds containing no polycycloalkenyl end groups, in admixture wih non-resinous vinyl monomers, are flexibilized by inclusion in the mixtures of about 1 to 20 parts by weight of a polyglycol moiety-comprising, vynil reactive, urethane oligomer per hundred parts of the alkyd.

Description: COMPOSITIONS OF UNSATURATED POLYESTERS OR POLYESTERAMIDES AND EFFICIENT FLEXIBILIZERS THEREFOR Unsaturated polyester resins are well-known compositions of many uses. The voluminous literature on polyesters is summarized in Vol. 18 of the Encyclo¬ pedia of Chemical Technology (Kirk-Oth er; 3d ed. ) at pages 575-594. More recently developed but also well known and highly useful are the unsaturated polyester¬ amide resins. (The "resins-" referred to are actually mixtures of the polyester or polyesteramide alkyds with non-resinous vinyl monomers such as styrene. ) It is well recognized that the latter resins could stand improvement in several respects. They typically undergo extensive shrinkage upon curing and - the cured resins possess relatively low impact strengths and percent elongations. U.S. Patent 3/448,172 - believed to constitute the nearest known prior art to the present invention - discloses substantial improvement in flexural strength and shrinkage of unsaturated polyester resins by adding relatively large amounts of certain "high molecular weight urethane polymers having an ordered arrangement of pendant unsaturation". re However, said urethane polymers are relatively complicated to make and - judging from the examples in the patent - the amount of the urethane polymer used must be about equal to the amount of the alkyd component 5 in order to affect the claimed improvement. The primary object of the present invention ' is to provide a less complicated and more efficient flexibilizer for unsaturated polyester and polyesteramide resins. r-- : 10 A further object is to provide, as such, flexibilizers, vinyl-terminated urethane oligomers (as subsequently defined herein) which are highly effective in flexibilizer/alkyd weight ratios as low as about 7/100. 15 Another object is to provide binary mixtures of the aforesaid flexibilizers with polyester or poly¬ esteramide alkyds from which the improved resins of the invention can be prepared by addition of a non-resinous vinyl monomer (reactive diluent). ^ 20 A particular object is to provide flexibilized polyester and polyesteramide resin compositions which, when cured, exhibit higher impact strengths, ductilities and percent elongations than do the unflexibilized resins per se. 25 Still other objects will be made apparent to those knowledgeable in the art by the following specifications and claims. SUBS .The foregoing objects are achieved by utilizing, as the flexibilizer component, relatively low molecular weight, branched or linear polymeric molecules made up of "polyglycol" and "urethane" units and terminated at at least one end by a group which is vinyl-reactive (i.e., contains a polymerizeable carbon-to-carbon double bond). The invention may be defined as a flexibilizer/ alkyd composition which does not phase separate upon curing comprising a. an unsaturated polyester and/or polyesteramide alkyd which includes no terminal polycycloalkenyl groups, and b. from 1 to 20 parts by weight of a flexibilizer comprising one or more urethane oligomers per hundred parts of said alkyd, said oligomers each having at least one vinyl-reactive end - group and being an addition product of a polyether glycol with an unsaturated isoeyanate or with a diisocyanate and an unsaturated compound comprising an -NCO or -CH-OH group, c. from 0 to 400 parts by weight of a non-resinous vinyl monomer per hundred parts of said alkyd, with the proviso that, when said alkyd comprises an unsaturated polyester, either the parts by weight of said oligomers per hundred parts of said, alkyd is not in excess of ll+9a/(a+e), where a and e are the parts by weight, respectively, of said polyesteramide and said polyester in said composition, SUBSTITUTESHEET ^ ~ • or said unsaturated compound is an unsaturated isocyanate, an alkenylphenol, a hydroxyalkyl- acrylate-initiated polyglycol or N-methylol- 5 acrylamide. As used herein, the term "polyester" is not intended to encompass the so-called "vinyl ester resins" (adducts of vinyl reactive carboxylic acids with epoxides) Unexpectedly, the flexibilizing effect of the 10 above-recited oligomers on isophthalate alkyds has been found to be substantially greater than on orthophthalate alkyds. In a process aspect, the invention may be defined as the method of making the subject compositions 15 which comprises*mixing the oligomer with the alkyd, either or both of which may be din the form of a preformed mixture with a non-resinous vinyl monomer. Suitable polyesters and polyesteraπri,des. The unsaturated polyesters suitable for the ■■. 20 practice of the invention are those deriveable, at least in part, from unsaturated polycarboxylic acids (maleic acid, for example) and polyhydroxy compounds (propylene glycol, for example). The unsaturated polyesteramides are those similarly deriveable from the 25 same unsaturated acids, the same polyols and, in addition, polyfunctional amines. SUBSTITUTESHEET The preferred polyesters may be defined as having a central ester chain comprising (a) dioxy groups of the formula: -O-R 4 -O- wherein R is a divalent organic radical selected from alkylene, oxy-linked alkylene, oxy-linked arylene, cycloalkylene, polycycloalkylene, bis(alkyl)cycloalkylene, bis(alkyl)polycycloalkylene, and arylene, and mόno-to-trihydroxy alkylene; and (b) diacyl residues of difunctional carboxylic acids, at least a part of said acids being ,β-unsaturated acids and any remainder being saturated aliphatic acids, aromatic acids or mixtures thereof. Similarly, the preferred polyesteramides may be defined as those having a central esteramide chain comprising (a) diamino groups of the formula: -N-R 2 -N- •1 '3 ΈΓ R J wherein 1 and R3 are independently selected from hydrogen, aliphatic, cycloaliphatic and aromatic or R 1 and R3 together form an aliphatic ring, and R is a divalent organic . JV B R S * radical selected from alkylene, oxy-linked alkylene, oxy-linked arylene, alkylene amino- linked "alkylene, alkylene amino-linked cyclo¬ alkylene, cycloalkylene, polycycloalkylene, arylene, alkylarylene bis(alkyl)cycloalkylene and bis(alkyl)polycycloalkylene, (b) dioxy groups of the formula: - -R 4 -O- wherein R is a divalent organic radical selected from alkylene, oxy-linked alkylene, oxy-linked arylene, cycloalkylene, polycycloalkylene, bis(alkyl)cycloalkylene, bis(alkyl)polycycloalkylene, * and arylene, and mono- to trihydroxy alkylene; and (c) diacyl residues of difunctional carboxylic acids, at least a part of said acids being α,β-unsaturated acids and any remainder being saturated aliphatic acids, aromatic acids or mixtures thereof. Typical diamine components of the foregoing polyesteramides are ethylene diamine, propylene diamine, hexane- ,6-diamine, piperazine, 4,4'-methylenebis- (cyclohexylamine), 2,2'-bis(4-aminocyclohexyl)propane, 4,4 l -diaminodiphenyl ether, bis(aminomethyl)norbornane, toluene diamine, bis(aminomethyl)dicyclopentadiene and homopiperazine. Typical polyamines are aminoethyl- piperazine and diethylenetriamine. *? 3 . _£ «? • ?' ΓSTUT 5= ...,. ' " ■ ~ ~ The polyol component of the polyester or polyesteramide is from the class having the formula: HO-R 4 -OH wherein R is as above defined. Mixtures of two or 5 more such polyols can be used. Representative such polyols are ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, dicyclopentadiene dimethanol, bis(hydroxymethyl)- r -. norbornane, methyl cyclohexanedimethanol, bis(hydro y- 10 propyDbisphenol A and other hydroxyalkylated bisphenols, pentaerythritol, sorbitol, glycerine and polypropoxylates of glycerine. When a polyesteramide is to be used, the ratio tff diamine to polyol therein can be varied within 15 wide limits. The latter ratio is significantly related to the solubility of the modified polyesteramide in reactive diluents, such as styrene, which are commonly employed with polyesteramides for many applications. As a general rule, the moles of diamine should not 20 exceed about 1/3 the combined moles of the polyol and diamine. The structure and size of the diamine mole¬ cule will determine to ' great extent the maximum amount of diamine that can be used. The unsaturated polycarboxylic acid component 25 of the polyester or polyesteramide preferably is largely composed of an α,β-unsaturated acid, such as maleic acid, fu aric acid, maleic anhydride or mixtures of those compounds. The latter acids are readily available, have good reactivity with the polyol and/or polyamine, 30 and result in products of good properties. Part of the α,β-unsaturated acid may be further replaced with a saturated or aromatic polycar¬ boxylic acid to vary the cross-linking potential and physical properties of the modified polyester or poly- esteramide. Such acids include the aliphatic acids such as adipic acid and the aromatic acids such as isophthalic acid. Replacement of part of the α,β-unsaturated acid with such acids is commonplace in the polyester art. Suitable selection of the acid and the amount thereof to achieve a desired purpose will be known to the skilled worker and can be optimized with simple preliminary experiments. Although not preferred, endomethylenetetra- hydrophthalic acid or anhydride also may be used. The corresponding methyl endomethylenetetrahydrophthalic anhydride or acid may be used instead of or in admixture with the unsubstituted anhydride or acid. Methods of preparing the foregoing alkyds are well known and will only be summarized herein, as follows. The total amount of acid varies as a function of the total polyol and polyamine ingredients used. Generally, one equivalent of dicarboxylic acid requires 1.00 to 1.10 equivalents of diol or diol/diamine mixture. The unsaturated polyesters or polyesteramides are prepared by fusion reaction of the a,β-unsaturated polycarboxylic acid and the polyol (polyamine) components with the removal of water. Other alternate methods will be recognized by the skilled worker. For example, unsaturated polyesters or polyesteramides are prepared STITUTESHEET by reaction of the α,β-unsaturated polycarboxylic acid and monoepoxides as total or partial glycol substitutes. Finally, although less preferred, diesters of α,β-unsaturated dicarboxylic acids and polyols may be re cted in a transesterification reaction to provide unsaturated polyesters. Suitable urethane oligomers The flexibilizer component of the compositions of the invention is a polyglycol moiety-comprising urethane oligomer having at least two end groups, at least one of which is vinyl reactive. The oligomer may be branched or linear but does not include substantial proportions of species having pendant, as well as terminal, vinyl groups. Preferably, it has only one to a few branches and includes no species with pendant vinyl groups. As used herein, the term "pendant" refers to a vinyl group attached to an oligomeric chain through a rel tively short linking group which itself is non- oligomeric, i.e., is not made up of repeating units. In contrast, "terminal" vinyl groups are found only at the ends of oligomeric chains - which terminate at their opposite ends either in links to other oligomeric chains or in vinyl groups. The oligomers of this type disclosed (as "monomers") in U.S. Patents 3,297,745 and 4,360,753 are generally suitable for the practice of the present invention. Similar oligomers in which the end groups are incorporated as hydroxyalkyl acrylate-initiated polyglycols, rather than as the hydroxyalkyl acrylates per se, are not only suitable but advantageous in the flexibilizer role. *-*-*.»---_- ... - w ■ ι_ ^.ΠGFJ 1 ° Λ - * • - . Also suitable oligomers are the bis(N-vinylcar- bamates) formed by the reaction of an unsaturated isocyanate with a polyglycol. Suitable such isocyanates are vinyl isocyanate and isopropenyl isocyanate - as disclosed in U.S. Patent 3,598,866; see Example 8 therein. Similarly, polyadducts of isocyanatoethyl ethacrylate, allyl isocyanate, allyl isothiocyanate or allyl glycidyl ether with polyglycols also may be used as the flexibilizing component. The flexibilizing component of the compositions of the invention alternatively may be of the novel type described in co-pending U.S. Patent Number 4,486,582, issued December 4, 1984. This type of flexibilizer is prepared by the reaction of a vinyl- or acryloxy- substituted phenol or phenol-initiated polyol with at least one of the terminal isocyanate (or isothiocyanate) groups in a urethane oligomer formed by reaction of an excess of a difunctional isocyanate (or thiocyanate) - with a polyol. The preferred vinyl-substituted phenol for this purpose is phenol itself, substituted by an isopropenyl group. However, such other phenols as cresols ring-substituted with ethenyl, allyl or isopropenyl groups are also suitable and the polyol portion in any or all of the molecules may be terminated by an -NH- group. The most generally suitable and"economic flexibilizers presently known of sure oligomeric reaction products of (1) a diisocyanate, (2) a hydroxy- or aminoalkylacrylate and (3) a polyglycol or amino-capped polyglycol. In these oligomers,. the alkyl portion of the hydroxy- or aminoalkylacrylate may be interrupted SUB by one or more oxygen or sulfur atoms; i.e., the hydroxy- substituted acrylate may be a monoacrylate of diethylene- or tripropylene glycol, for example. Also, N-methylol acrylamide may be employed in place of a hydroxyalkyl- 5 acrylate as a source of vinyl end groups in such oligomers. Similarly, the vinyl reactive end group(s) of the oligomer may derive from an alkenylamine which is N-substituted by a hydroxy-terminated group; for example, the adduct of from one to several molecules of 10 an alkylene oxide with vinyl-, diallyl- or divinylamine /=--. may be reacted with the terminal isocyanate groups in an intermediate polyol/diisocyanate reaction product. In each of the several foregoing types of unsaturated adducts, the polyglycol moiety preferably 15 is derived from a diol (by base catalyzed reaction with an alkylene oxide) but desirably is based on (initiated ' with) a triol - such as glycerine or triethanolamine, for example -, or on an aminoalcohol or a polyfunctional amine. Since isocyanates will react with -NΞ, as well 20 as with -OH (or -SH) groups, the polyglycol unit(s) may be amino-capped and/or the -OH function in an end group precursor - such as 2-hydroxypropyl methacrylate, for <-. example - may be replaced by an -NH, function. Preferably, the oligomer has at least two 25 vinyl-reactive end-groups. However, this is not indispensable; species having only one vinyl-reactive end group are considered suitable for the practice of the present invention. On the other hand, a total of three terminal vinyl groups (resulting from use of a 30 triol-based polyglycol) is considered advantageous. r« B -;STΓΓUTE SHEET . SA/US All ramifications of the flexibilizer component are of course within the constraint that the oligomer(s) exhibit the requisite degree of compatibility with the other components (the alkyd or alkyd and vinyl monomer components) of the cured composition of the invention. This can readily be checked for any candidate oligomer, without undue experimentation, in a manner which will be apparent to those knowledgeable in the art. Methods of Preparation of Flexibilizers. The vinyl terminated urethane oligomers disclosed in U.S. Patents 3,297,745 and 4,360,653 are generally suitable for use as flexibilizers in the present invention and may be prepared by the several methods disclosed in said patents. The latter methods are also generally applicable to.the preparation of oligomers in which the terminal unsaturation is derived from a hydroxyacrylate-initiated polyol or a phenol-initiated polyol in which the phenol is ring-substituted with an alkenyl group. Preparation of oligomers by the reaction of an unsaturated isocyanate, such as isopropenyl isocyanate, allyl isothiocyanate and isocyanatoethyl methacryl te, for example, with a polyglycol is exemplified herein and does not require any procedures unfamiliar to polyurethane chemists. In preparing oligomers by the condensation of a hydroxy or aminoalkylacrylate, a d±isocyanate and a polyglycol, whether the isocyanate is first reacted with the acrylate or the polyglycol is not critical. In either case, however, the reactant ratio in the SUBSTITUTESHEET initial condensation must be controlled to insure the presence of the requisite, unconverted isocyanate end-groups in the intermediate product. The reaction sequence does effect and can be utilized to manipulate the viscosity (average molecular weight) of the flexibilizer. If the isocyanate is first reacted with the hydroxyacrylate, the viscosity of the final product will be lower than when the iso¬ cyanate is first reacted with the polyol. Flexibilizer Content The weight percent of the oligomer in the alkyd/vinyl monomer mixtures of the invention can range from 1 to 10 percent. Preferably, however, the content of flexibilizer in the composition is from 4 to 8 percent; the range of from 5 to 7.5 percent being particularly * preferred. In any case, the content of flexibilizer preferably is such that "phasing", i.e., formation of a visibly distinct, second phase, does not result when the composition is cured. Copolymerizable Vinyl Monomer The compositions of the invention preferably comprise a non-resinous, vinyl reactive monomer - which preferably is styrene. Other specific such monomers; for example, are vinyl toluene, t-butylstyrene, divinyl benzene and chlorostyrene. Various acrylates, as exemplified by dicyclopentadienyl acrylate, sec-butyl acrylate and ethylacrylate, though less preferred, are considered suitable for the practice of the present invention. Thus, suitable vinylic monomers generally -J ~xd> —- UTΞ SHEET are those commonly copolymerized with polymers having terminal or pendant, vinyl-reactive, olefinic or cyclo- olefinic double bonds. Such monomers are well catalogued in the prior art. 5 The well known catalysts and procedures for the latter type of copolymerization are also generally applicable to "curing" (chain extension and cross- linking) of the compositions of the present invention which comprise vinyl monomers. Those compositions 10 w ich do not include vinylic monomers are considered r -, novel per se and may be cured by use of the same catalysts and procedures to thermoset products. The vinyl monomer, frequently called a reactive diluent, may be employed within a wide range 15 of concentration of from 20 to 80 percent of diluent to 80 to 20 percent of the .polyester or polyesteramide (from 25 to 400 pha (parts per hundred parts of alkyd)). The optimum amount will depend in large measure on the particular alkyd, the diluent and the properties 20 desired in the uncured and the cured states but will often be 50 to 80 pha. Reactive diluents are employed principally to adjust the viscosity of a resin blend to J" χ permit its facile use in a given fabrication procedure. A coating formulation will usually require a lower 25 viscosity than a molding formulation. When the diluent is styrene, the preferred content thereof is from 60 to 70 pha. The weight ratio of the flexibilizer component to the alkyd component in the alkyd/vinyl monomer 30 mixtures of the invention can range from 1/80 to 1/5, i.e., from 1 to 20 pha. . ' Preferably-, the ratio is within the range of from 1/50 to 8/50, or from 2 to 16 pha. S-' SSTITUTESHEET Other additives that are conventional in the polyester and polyesteramide art may also be included in formulations based upon the flexibilized alkyds. Thus, fillers, pigments and other colorants, reinforcing 5 fibers, and othe additives may be added to serve their intended function. The flexibilized polyesters and polyesteramides are curable by known catalyst systems. Peroxides, such as methylethylketone peroxides, can be used with or 10 without known promoters, such as cobalt octoate or /" •*"• cobalt naphthenate, that function with such peroxides. Acyl peroxides, such as benzoyl peroxides can be used with or without promoters such as tertiary amines, including typically dimethyl aniline and N,N-dimethyl-p- 15 toluidine. The concentrations of catalyst and promoter are adjusted within known limits of from 0.1 to 3.0 weight percent depending on the rate of cure desired, the magnitude of the generated exo her ' and for other known purposes. Known gelation retarding agents, such 20 as p-benzoquinone, can be employed in the curing system. The flexibilized resin compositions of the present invention are especially suited for use in ' ' * -•• applications requiring improved flexibility in conjunc¬ tion with enhanced impact resistance as well as reduced 25 shrinkage upon curing ("low profile"). Typical of these applications are bulk and sheet molding compounds and the parts prepared from said compounds. The uncured alkyd/flexibilizer compositions of the invention which do not include vinyl monomers 30 (such as styrene, for example) have utility as inter¬ mediate materials which can be mixed with such monomers and cured. S3 .. __?3T!TUTESHEET Examples The following examples are for purposes of illustration and are not be construed as limiting the present invention in a manner inconsistent with the 5 clt-ims appended to these specifications. Those material.names capitalized in the examples are registered trade names. Where convenient, flexibilizers hereinafter are designated as "VRP"s (vinyl reactive plasticizers). . 10 I. Preparation of Flexibilizers (Not examples of the invention.) A(l). Preparation of a VRP from a polypropylene glycol, toluene d socyanate and hydroxypropylaery1ate. A VRP having the statistical structure (A-l) ac - --34 20 was prepared in two steps; the polyglycol was reacted with the diisocyanate, in the presence of stannous octoate, until the -OH band in the infrared (IR) spectrum of the reaction mixture disappeared and the hydroxyacrylate was then added to react out the 25 remaining isocyanate groups. The detailed procedure follows. •ώ* l , -_..s iITUTESHEET A 0.12 percent solution of stannous octoate (3.355 grams) in 2811.12 grams (1.4056 g moles) of polypropylene glycol (DOW: P-2000) was added over a period of about 13/4 hours to 488.4 grams (2.8111 g 5 moles) of toluene diisocyanate (Type I, NACONATE 80; registered trade name of The Dow Chemical Company) 80/20 mixture of 2,4- and 2,6-isomers) in a 5-liter resin flask fitted with a reflux condenser and stirrer. The flask contents were heated from an initial tempera- 10 ture of 60°C to a final temperature of 70°C during the addition. Stirring was continued at the latter tempera¬ ture for another 3/4 hour, at which time the -OH v infrared peak had disappeared. A preformed solution of 1.815 grams of phenothiazine (vinyl polymerization inhibito 15 in 330 grams (2.54 g moles) of 2-hydroxypropyl acrylate was then added and the resulting mixture stirred at a temperature of 82-86°C for an additional 2/3 hour, at which point no further decrease in isocyanate absorption (IR) or increase in carbonyl absorption was observable. 20 The product, designated herein as VRP- , had a Gardener viscosity, at 20 β C, equivalent to 79,200 cps. A(2). Preparation of a VRP having -an ideal structure incorporating two polyglycol units and three diisocyanate units. 25 A mixture of 2473 grams (1.2365 gram moles) of polypropylene glycol (P-2000) and 1 gram of stannous octoate was added with stirring to a mixture of 330 grams (1\897 g moles) of toluene diisocyanate (80/20 mixture of 2,4-and 2,6-isomers) and 0.465 grams of 30 stannous octoate and stirring was continued until the reaction was complete (-OH IR absorption gone). 162.5 Grams (1.25 g moles) of 2-hydroxyethyl acrylate (and a small amount of methylethylhydroquinone vinyl stabilizer) was then stirred into the reaction mixture - * -"i-- _ _ and allowed to react until the -OH IR absorption was minimized and the urethane carbonyl absorption maximized. A small amount of toluene diisocyanate was added to react out the last of the -OΞ and then the residual -NCO was reacted out by adding about 0.5-1.0 grams of isopropanol. The resulting product, a very viscous, clear light yellow-colored liquid, was then diluted with styrene to an 80 wt. percent VRP content solution, designated herein as "VRP-A2". A(3-6). Preparation of a series of type A VRP's using polyglycols of different molecular weights and/or composition. Toluene diisocyanate (2.0 moles) and pheno- thiazine (0.05 percent) were added to a reactor and heated to 60°C with stirring. The toluene diisocyanate used was an 80 to 20 weight percent mixture of the 2,4- and 2,6 isomers, respectively. Hydroxypropyl acrylate (2.0 moles) was mixed with stannous octoate catalyst (0.12 weight percent) and this mixture was added to the reactor over a 1.5 to 2.0 hour period. The reaction was allowed to progress at the 60°C reaction temperature until infrared spectrophotometric analysis of a film sample of the reaction product demonstrated essentially complete reaction (disappearance of hydrox 1 group), typically 2.0 to 3.0 hours. At that time, the polyglycol component was added in an amount to provide 1.0 mole of reactive hydroxyl groups. The polyglycol component was chosen from the following: (3) polypropylene glycol of 1200 average molecular weight, (4) polypropylene glycol of 2000 average molecular weight, (5) polypropylene glycol of 4000 average molecular weight, or (6) the 3000 average molecular weight adduct of glycerin and a 92.0 percent propylene oxide-8.0 percent ethylene oxide mixture. The reaction was continued at the 60°C tempera- 5 ture until infrared spectrophotometric analysis indicated essentially complete reaction (disappearance of the isocyanate and hydroxyl groups), typically 3.0 to 4.0 hours. The reactor was cooled and the vinyl reactive plasticizer recovered and designated as VRP-(A4), 10 -(A5), etc. r > NOTE: The 400 molecular weight polyglycol included about 30 wt. percent of a species having only one terminal hydroxy group, the other end group being B. Preparation of VRP's from isocyanatoethyl meth¬ acrylate and a polyol. (1) 80.4 grams (0.52 g mole) of isocyanatoethyl 20 methacrylate, 519.6 grams (0.26 g mole) of F-2000, 0.66 -~- grams of stannous octoate (catalyst) and 0.05 gram of phenothiazine (vinyl stabilizer) were stirred together in a round-bottomed flask for 3 hours. The reaction proceeded, to completion, spontaneously, i.e., without 25 heating. The resultant VRP exhibited a low viscosity and had the statistical structure (B-l): CH, 0 H 0 . I 3 M \-h 0 H 0 CH tf t H 2 C=C - C-0-CH 2 -CH 2 -N-C-O^CH 2 -CH-0*> χ C-N-CH 2 -CH 2 -0-C-C=CH 2 x » -34. SHEET B" 3A/US (2) A higher molecular weight VRP was made in two steps. 25.2 Grams (0.145 g mole) of toluene diisocyanate (Type I NACONATE 80) was added slowly to a solution of 0.69 gram of stannous octoate in 574.8 grams (0.2874 g mole) of P-2000. After stirring for several hours, the resulting glycol-extended diurethane was reacted with 44.5 grams (0.287 g mole) of isocyanatoethyl methacrylate as in (1) above. The resultant VRP was substantially more viscous than that obtained in preparation B-(l) 10 and had the statistical structure (B-2): 15 (3) Preparation of type (1) oligomer at elevated temperature . Isocyanatoethylmethacrylate (1.0 mole) was added to a reactor and heated to 70°C with stirring. Polypropylene glycol of 2000 average molecular weight 20 was mixed with stannous octoate catalyst (0.10 weight percent) and a sufficient amount was added to the reactor so as to provide 0.50 mole of reactive hydroxyl groups. The reaction was continued at the 70°C tempera¬ ture for 30 minutes. At this time, infrared spectrophoto- 25 metric analysis indicated essentially complete reaction (disappearance of the isocyanate and hydroxyl groups). The reactor was cooled and the vinyl reactive plasticizer (VRP B3) recovered. Sϋ3^τ_τ g* ** *> SHEET C. Preparation of a vinyl-terminated urethane oligomer ("VRP-C") comprising isopropenyl phenol-derived end groups. Toluene diisocyanate (0.255 mole, 44.41 5 grams), p-isopropenyl phenol (0.255 mole, 34.21 grams), and phenothiazine (0.055 weight percent, 0.167 grams) were added to a glass reactor and maintained under a nitrogen atmosphere with stirring. The toluene diiso¬ cyanate was an 80 to 20 weight percent mixture of the 10 2,4- and 2,6-isomers, respectively. The p-isopropenyl phenol contained less than 1.6 weight percent di er and only a trace of residual phenol. The reactants were C ~~ heated to 45°C. A catalyst package consisting of an organo tin salt commercially available from Witco 15 Chemical Co. as FOMREZ UL-28 (0.152 grams) and a tertiary amine commercially available from Abbot Labs as FOLYCAT DBU (0.152 grams) was added to the stirred slurry and air cooling of the reactor exterior"was started. A maximum exotherm.to 82°C occurred four minutes later. 20 Cooling reduced the temperature of the reactor contents to 60°C and this temperature was maintained for 56 minutes. At this time, infrared spectrophotometric analysis of a film sample of the transparent, pale yellow-colored reaction product demonstrated that the C" "* 25 reaction of the isocyanate with the phenolic hydroxyl was essentially complete (disappearance of hydroxyl group, appearance of carbonyl group). Polypropylene glycol (0.1275 mole, 225.0 grams) with an average molecular weight of 2000 was added to the reactor, 30 followed by the addition of more catalyst, Witco FOMREZ UL-28 (0.076 grams) and POLYCAT DBU (0.152 grams). A maximum exotherm to 68°C occurred eleven minutes later. Cooling reduced the reaction temperature to 65°C and this reaction temperature was maintained for 3.8 hours. CJSSTΪTUTE SHEET At this time, infrared spectrophotometric analysis of a film sample of the white-colored, viscous, liquid reaction product demonstrated that the reaction of the remaining isocyanate groups with the aliphatic hydroxyl groups was coωplete. The reactor contents were cooled and a vinyl-reactive "oligomer" (VRP-C) of the following statistical formula (C) was recovered: where x = -34. D. Preparation of a VRP comprising allylene oxide- extended hydroxy-functional acrylate end groups. 15 Polypropylene glycol (0.06375 mole, 127.5 grams) with an average molecular weight of 2000 and contain ng dissolved stannous octoate (0.1105 gram) and an organo tin salt commercially available from Witco Chemical Co. as FOMREZ UL-28 (0.1105 gram) was added 20 over a one-minute period to a glass reactor containing stirred toluene diisocyanate (0.1275 mole, 22.21 grams) under a nitrogen atmosphere. The toluene diisocyanate used was an 80 to 20 weight percent mixture of the 2,4- and 2,6-isomers, respectively. A maximum exotherm to . 25 51°C occurred three minutes later; then the reaction temperature was increased to 60 β C. After 44 minutes at the 60°C reaction temperature, infrared spectrophotometric analysis of a film sample of the transparent reaction product demonstrated that the reaction of the isocyanate 30 with the aliphatic hydroxyl group was complete (dis¬ appearance of hydroxyl group, appearance of urethane • carbonyl group). 51.19 Grams (0.1275 moles) of the mono(2-hydroxyethy1aery1ate)ether of pentapropylene glycol-1,2 was then added. The reaction temperature was maintained at 60°C and after 78 minutes, infrared 5 spectrophotometric analysis of a film sample of the transparent reaction product demonstrated that the reaction of the remaining isocyanate groups with the aliphatic hydroxyl groups was complete. Ξydroquinone (100 ppm) was added to the reactor and the resulting 10 VRP (designated herein as VRP-D) was recovered. The oligomer (VRP-D) had the statistical C-, structure (D): II. Representative Alkyd Preparations (Not an example of the invention. ) C ' 20 1. An orthophthalic polyester was prepared as follows: Maleic anhydride (323.60 grams, 3.30 moles) and phthalic anhydride (325.86 grams, 2.20 moles) were added to a reactor and heated to a white-colored stirred 25 slurry maintained at 100°C under a nitrogen atmosphere. Propylene glycol (460.41 grams, 6.05 moles) was added and a maximum exotherm of 140°C resulted nineteen minutes later. At that time, nitrogen sparging was SUSST.TUTE SHEET s -?2s increased to 0.5 liter per minute, a steam condenser was started, and the temperature controller was set at 160°C. That temperature was achieved five minutes later. After two hours, the temperature controller was set at 205°C and that temperature was achieved thirty- wo minutes later. After 8.0 hours at the 205°C reaction temperature, a..total of 103 milliliters of water layer had accumulated in a Dean Stark trap. The reactor was cooled to 165°C and 100 ppm of hydroquinone was added. 10 The unsaturated polyester alkyd was recovered as a clear, transparent solid with a final acid number of r 27.2. It was designated as alkyd 1. III. Examples of the Invention In each of the following examples, styrene/alkyd 15 mixtures including £nd not including a VRP were prepared and compared as to physical and mechanical properties. Example 1 Portions of the foregoing alkyd (1) were mixed with styrene and VRP-A1 in the amounts given in 20 the following tabulation. t. Polyester Vinyl Reactive Alkyd Styrene Plasticizer Formulation (qrams/%) ( rams /%) (grams %/pha—^ 1 199.5/57.0 136.5/39.0 14.0/4.0/7.0 25 2 199.5/57.0 126.0/36.0 24.5/7.0/12.3 3 199.5/57.0 150.5/43.0 0 Note: 1/ pha « parts VRP per hundred parts of alkyd. Si * $ * *_> The resin formulations (1-3) were used to determine SPI gel and cure characteristics (84°C), Brookfield viscosity (25 β C), and a clear, unfilled 1/8" casting was made for heat distortion temperature, tensile and flexural strength, flexural modulus, percent elongation, and average Barcol hardness (934-1 scale) determinations. ' The clear casting was prepared using a cure system of 1.0 percent benzoyl peroxide and 0.01 percent N,N-dimethylaniline at room temperature, followed by post-curing for 2.0 hours at 100°C. Mechanical properties of tensile (6) and flexural (6) test pieces were determined using an Instron machine with standard test methods (ASTM D-638 and D-790). Heat distortion temperatures were determined using an Aminco Plastic Deflection Tester (American Instrument Company) with standard test methods (ASTM D-648). The results are reported in Table 1. TABLE 1 Wt. % VRP-A1 in Formulation 0.0 4.0 7.0 Brookfield Viscosity (cp) 239 566 1153 SPI Gel Test Gel time (min) ,2.6 4.0 5.5 cure time (min) 4.0 5.5 7.3 Maximum exotherm (°C) 231 224 210 Average Barcol Hardness 48 42 35 Heat Distortion Temperature (°C) 1 10022..88 98.9 92.2 Tensile Strength (kPa) 65,500 61,400 59,300 Elongation (%) 2.0 2.5 3.7 Flexural Strength (kPa) 130,300 125,500 105,500 Flexural Modulus xlθ '5 (kPa) 43.4 37.9 31.7 " J-JT •' - •• 'πJTESHEET It will be seen that each property responded in a regular manner to the amount of VRP present in-the formulation. The increases in percent elongation resulting from inclusion of the VRP were noteworthy, whereas the decreases in heat distortion temperatnre, tensile strength and flexural strength were quite acceptable. Example 2 - Effect of VRP-Al on Mixture of Styrene with an Isophthalate Polyester Alkyd A portion of VRP-Al was mixed with one of two portions of a styrenat ' ed, commercial grade, unsaturated isophthalate alkyd prepared from isophthalic acid, maleic anhydride and propylene glycol. No VRP was added to the second portion. The properties of the two materials were compared in.the manner of Example 1. The results are given in Table 2. TABLE 2 Wt. % VRP-Al in Mixture 7.5 Brookfield Viscosity (cp) 457 224 SPI Gel Test Gel time (min) 5.7 4.1 Cure time (min) 9.2 6.1 Maximum exotherm (°C) 186 215 Average Barcol Hardness 34 47 Heat Distortion Temperature (°C) 92.2 97.8 Tensile Strength (kPa) 56,500 66,900 Elongation (%) 5.6 2.1 Flexural Strength (kPa) 106,200- 149,600 Flexural Modulus xlO (kPa) 31 42.7 SUBSTITUTE SHEET It will be seen that the increase in percent elongation resulting from inclusion of about 7 percent VRP was dramatically greater and the decrease in heat distortion temperature dramatically less than for the orthophthalate alkyd of Example 1. This clearly demonstrates that effective flexibilization of one type of alkyd by vinyl-terminated urethane oligomers does not make it obvious that a different type of alkyd will be effectively flexibilized by the same oligomers. Example 3 - Effect of VRP-Al on Mixture of Styrene with an Inherehtly " More Brittle - But Also More Fire Resistant Polyester Alkyd A portion of VRP-Al was mixed with one of two portions of a mixture of styrene with a commercial grade, unsaturated polyester alkyd prepared from chlorendic anhydride, maleic anhydride and propoxylated neopentyl glycol. The properties of the two materials were compared in the manner of Example 1. The results are given in Table 3. SUBSTITUTE SHEET TABLE 3 Wt. % VRP-Al in Mixture 7.5 0 5 Brookfield Viscosity (cp) 417 228 SPI Gel Test Gel time (min) 7.7 4.1 Cure time (min) 11.4 6.4 Maximum exotherm (°C) 210 231 10 Average Barcol Hardness 45 49 Heat Distortion Temperature (°C) 97.8 124 Tensile Strength (kPa) 57,900 60,000 Elongation (%) 2.2 2.0 Flexural Strength (kPa) 118,600 113,700 15 Flexural Modulus xlθ "5 (kPa) 37.2 42.7 It will be seen that about a 10 percent increase in percent elongation was achieved at the expense of a substantial decrease in heat distortion temperature (ΞDT). However, the ΞDT of the unflexibilized 20 resin was high enough to start with so that the ΞDT after flexibilisation was still acceptable for practically all common applications of polyester resins. Example 4 - Effects of VRP-Al on Impact Strengths of the Alkyd/styrene Mixtures of Examples 1-3 25 Ten 6.35 x 1.27 x 0.16 cm test pieces were prepared from castings of.each of the formulations (mixtures) compared in Tables 1-3. Unnotched Izod I' ^ rs.-^ .. SHEET impact strengths, were determined from the test pieces by ASTM test method D-256, using a TMI Impact Tester No. 43-1. The results are given in Table 4. TABLE 4 Impact Alkyd/styrene Wt. % - Strength Mixture of VRP-Al Joules/met. Example 1 0.0 123 4.0 123 7.0 139 Example 2 0.0 155 7.5 331 Example 3 0.0 133.5 7.5 91 It will be seen, again, that the favorable effect of the VRP (on impact strength) is dramatically greater for the isophthalate alkyd resin of Example 2 than for the orthophthalate alkyd resin of Example 1. The reason for the apparently unfavorable effect on the resin of Example 3 is not known. Example 5 - Effects of 2.5, 5.0 and 7.5 Wt. Pereents of VRP's A3-6 on Mechanical Properties of an Orthophthalic Molding Resin Portions of a styrenated, commercial grade, unsaturated orthophthalic polyester molding resin prepared by the reaction of phthalic anhydride (14.3 SU STITIJTE SHEET IB A/ mole percent), maleic anhydride (33.3 mole percent) and propylene glycol (52.4 mole percent) were formulated to contain 2.5, 5.0 and 7.5 wt. percent of each of VRP's A3-6. An additional portion of the resin, containing no VRP, was taken for comparison. The mechanical properties of the cured mixtures were determined by the method of Example 1. The results are given in Table 5. - . * _τ_ r --- ..'.-•.;'*. •1_ • "I_f'-A™-* ■ SHEET" '_ TABLE 5 t . % VRP Wt . % VRP Wt. % VRI X Wt . % VRP Tensile Strength Flexural Modulus Elongation Flexural Strength VRP xlθ "3 <kP) % (kPa) xl0~ 5 (kPa) 2.5 5.0 7.5 2.5 5.0 7.5 2.5 5.0 7.5 2.5 5.0 7.5 A3 51.7 47.6 48.3 1.6 1.7 1.7 106,900 104,100 101,400 42 36.5 35.8 A4 33.θ 41.4 34.5 1.1 1.6 1.4 112,400 91,700 76,500 40 33.8 32.4 A5 32.4 28.3 34.5 1.1 1.1 1.3 71,000 65,500 63,400 40 32.4 31 A6 42.7 51 46.9 1.4 2.2 1.9 109,000 88,900 105,000 37.2 34.5 32.4 None 24. 1 4. 1 101,000 37 .9 Each VRP a reaction product of hydroxypropy aerylate, toluene diisocyanate and a polyglycol as follows: (A3) Polypropylene glycol of 1200 average mol. wt. (A4) " " " 2000 •' » " (A5) « " " 4000 " " » (A6) 3000 average mol. wt. adduct of 92.0% propylene oxide and 8.0% ethylene oxide mixture with glycerin. It will be seen that a good balance of properties resulted at a content of about 5 wt. percent of each VRP. However, dramatic improvements in tensile strength and percent elongation were obtained with all VRP's at all three wt. pereents. The A3 formulations also had better flexural strengths at all wt. pereents and the greatest decrease in flexural modulus (4.7x10 at 7.5 wt. percent A5, vs. 5.5x10 at 0 wt. percent) was not intolerable. Example 6 A portion of the styrenated commercial grade unsaturated orthophthalic polyester molding resin of Example 5 and the vinyl reactive plasticizer A6 were formulated to provide a 95.0, 5.0 percent solution, respectively. This solution was used to prepare a 0.15875 cm clear, unfilled casting and cured using the method of Example 1. A test piece was prepared from the clear, unfilled casting to have the following measurements: 16.51 cm length, 1.5875 cm width at tab ends, routed to a 1.016 cm width at center. An otherwise identical test piece "was prepared from another portion of the molding resin to which no VRP had been added. The test pieces were used for plane strain compression testing with applied tension using the methods of P. S. Bowden and J. A. Jukes reported in Journal of Material Science 3, 183 (1968) and 7, 52 (1972). Sample cross-sectional area was 0.16129 cm and tensile load was increased by 3889 kPa increments. The creep rate taken as yield was approximately 0.3048 cm/sec. Tension (kP) versus compression (kP) yield point values thus obtained were plotted. Tensile and compressive yield strength values were determined by extrapolation of the plotted biaxial yield line. Ductility was calculated as the ratio of tension at break to the tensile yield strength. The results are reported in Table 6. TABLE 6 Wt. % VRP A6 Ductility 0.51 less than 0.01 Tension, at Break, kPa 38,308 Compression at Break, kPa 53,650 Tensile Yield Strength, kPa 75,845 Compressive Yield Strength, kPa 105,942 * sample breaks at all test points. Example 7 - Effect of 5 Wt. Percent of VRP B3 on Mechanical Properties o " Molding Resin Used in Example " 5 Portions of the molding resin containing 0 and 5 wt. pereents of VRP B3 (derived from isocyanato¬ ethyl methacrylate and polyglycol P2000) were cured and their physical properties determined as in Example 1. The results are given in Table 7. '*•—' 4--- " t_ ' UTE SHEET s TABLE 7 Wt. % VRP B3 5 0 Brookfield Viscosity (cp) 739 720 Heat Distortion Temperature (°C) 107 111 Tensile Strength (kPa) 51,000 24,100 Elongation (%) 14.5 4.1 Flexural Strength (kPa) 101,000 101,400 Flexural Modulus xio " (kPa) 34.5 37.9 It will be seen that excellent flexibilization was achieved at the expense of quite minor decreases in ΞDT and flexural properties. Example 8 - Effect of 7.5 Wt. Percent of VRP-D on Physical and "" Mechanical Properties of Isophthalic Resin Used m Example 2 Portions of the styrenated isophthalic polyester were formulated to contain 0 and 7.5 wt. pereents of VRP-D. The physical and mechanical properties of the two materials given in Table 8 were determined as in Example 1 and the Plane Strain data given in Table 9 were determined as in Example 6, except that ductility wa's calculated as one minus the ratio of compression at break to the compressive yield strength. • -3! DESTITUTE SHEET ISA TABLE 8 Wt. % VRP-D^ _______ 0% Brookfield Viscosity (cp) • 449 224 5 SPI Gel Test Gel time (min) 6.5 4.1 Cure time (min) 10.5 6.1 Maximum exotherm (°C) 83 215 Average Barcol Hardness 25 47 10 Ξeat Distortion Temperature ( β C) 82.8 97.8 £ > ■ . Tensile Strength (kPa) 49,600 66,900 Elongation (%) 26.2 14.5 Flexural Strength (kPa) ,00,000 149,600 Flexural Modulus xlθ "5 (kPa) 29.6 42.7 15 Notes: 1 Derived from P-2000, TDI and mono(2-hydroxy- ■ ethylacrylate)ether of pentapropylene glycol 1,2. 2/ From Table 2, Example 2. TABLE 9 20 Wt. % VRP D 7.5 Ductility 0.76 0.49 Tension at Break, (kPa) 51,754 48,472 Compression at Break, (kPa) 23,664 72,556 25 Tensile Yield Strength, (kPa) 67,916 99,977 Compressive Yield Strength, (kPa) 98,467 143,347 SϋΘS The Izod Impact Strength (unnotched) of the cured 7.5 percent VRP-D formulation was 240 Joules/met. as compared to 155 for an otherwise identical portion of the styrenated isophthalate resin containing no VRP 5 (same as given for "Example 2" in Table 4). It will be seen that the VRP effectively flexibilized the isophthalate alkyd/styrene mixture without reducing the ΞDT to an intolerable extent. r ■ SUBSTITUTE SHEET

Claims: A AMMEENNDDEEDD C CLLAAIIMMSS [received by the International Bureau on 01 July 1985 (01.07.85); original claims 1-21 replaced by new claims 1-19 (6 pages)] 1. A flexibilizer/alkyd composition which does not phase separate upon curing comprising a. an unsaturated polyester and/or polyesteramide alkyd which includes no terminal polycyclo- alkenyl groups, and b. from 1 to 20 parts by weight of a flexibil¬ izer comprising one or more urethane oligomers per hundred parts of said alkyd, said oligomers each having at least one vinyl-reactive end group and being an addition product of a polyether glycol with an unsaturated isocyanate or with a diisocyanate and an unsaturated compound comprising an -NCO or -CH-OH group, c. from 0 to 400 parts by weight of a non- resinous vinyl monomer per hundred parts of said alkyd. with the proviso that, when said alkyd comprises an unsaturated polyester, either the parts by weight of said oligomers per hundred parts of said alkyd is not in excess of ll+9a/(a+e), where a and e are the parts by weight, respectively, of said polyesteramide and said polyester in said composition, or said unsaturated compound is an unsaturated isocyanate, an alkenylphenol, a hydroxyalkylacrylate-initiated polyglycol or N-methylolacrylamide. 2. The composition of Claim 1 in which said alkyd is said unsaturated polyesteramide and said unsaturated compound is a hydroxyalkylaerylate, an unsaturated isocyanate, an alkenylphenol, a hydroxyalkylacrylate-initiated polyglycol or N-methylolacrylamide. 3. The composition of Claim 1 in which said alkyd is an unsaturated isophthalic polyester. 4. The composition of Claim 1, 2, or 3 in which said flexibilizer comprises an addition product of said polyether glycol selected with a) an isocyanatoethylmethacrylate alone or together with a diisocyanate, b) a diisocyanate and a hydroxyalkyl- acrylate-initiated polyglycol, c) a diisocyanate and p-isopropenylphenol, or d) a diisocyanate and N-methylol acrylamide. 5. The composition of Claim 1, 2, or 3 in which: said flexibilizer comprises an addition product of said polyether glycol with a diisocyanate and a hydroxyalkyl¬ acrylate-initiated polyglycol, an unsaturated isocyanate p-isoproponyl phenol or N-methylolacrylamide; said vinyl monomer is styrene and is present in the amount of from 60 to 70 parts by weight per hundred parts of said alkyd. 6. The composition of any one of the preceding claims in which said non-resinous vinyl monomer is present in an amount of from 50 to 80 parts by weight per hundred parts of said alkyd. 7. The composition of Claim 6 in which said monomer is styrene and is present in an amount of from 60 to 70 parts by weight per hundred parts of said * alkyd. 8. The composition of Claims 1 to 4 in which said polyether glycol is a polypropylene glycol having a molecular weight of from 2000 to 3000. 9. The composition of Claim 8 in which said diisocyanate is tolylene diisocyanate. 10. The composition of Claim 9 in which said oligomer is the reaction product of polypropylene glycol, tolylene diisocyanate, and 2-hydroxypropyl acrylate. 11. The composition of Claim 10 in which said oligomer has the statistical structure X=-34 12. The composition of Claim 5 in which said oligomer has the statistical structure CH 3 0 H O CH 3 0 H 0 CH 3 H 2 C=C - C-0-C3ϊ 2 -OT 2 -N-C-0^CH 2 -CH*-0) χ C-N-CH 2 -0-C-C-=CH 2 X=-34 13. The composition of Claim 10 in which said oligomer has the statistical structure 14. A method of making a flexibilized alkyd resin, which does not phase separate upon curing, by mixing together a. an alkyd comprising an unsaturated polyester and/or polyesteramide which includes no terminal polycycloalkenyl groups, and b. from 1 to 20 parts by weight of a flexibil¬ izer comprising one or more urethane oligomers per hundred parts of said alkyd, said oligomers each having at least one vinyl- reactive end group and being an addition product of a polyether glycol with an unsaturated isocyanate or with a diisocyanate and an unsaturated compound comprising an -NCO or -CH-OH group, and c. from 0 to 400 parts by weight of a non-resinous vinyl monomer per hundred parts of said alkyd, with the proviso that, when said alkyd comprises an unsaturated polyester, either the parts by weight of said oligomers per hundred parts of said alkyd is not in excess of ll+9a/(a+e), where a and e are the parts by weight, respectively, of said polyesteramide and said polyester in said composition. or said unsaturated compound is an unsaturated isocyanate, an alkenylphenol, a hydroxyalkylacrylate-initiated polyglycol or N-methylol-acrylamide. 15. The method of Claim 14 in which the amount of said non-resinous vinyl monomer mixed with said alkyd and/or oligomer(s) is from 50 to 80 parts by weight per 100 parts of the alkyd. - 16. The method of Claim.14 or 15 in which said alkyd is an isophthalic polyester and said monomer is styrene. 17. The method of Claim 14 in which said polyglycol moiety is derived from a triol and the number of end groups in said oligomer is 3. 18. The method of any one of Claims 14 to 17, including the step of curing the resultant mixture. 19. A cured product made by the method of Claim 18.

Inventors: HEFNER ROBERT E JR, MARTIN PATRICK H, STEVENS GREGORY A, HEFNER, ROBERT, E., JR., MARTIN, PATRICK, H., STEVENS, GREGORY, A.
Applicants: DOW CHEMICAL CO, THE DOW CHEMICAL COMPANY
Application year: 1985
Main classification: C08L67
IPC codes: C08L67, C08L77