# United States Patent [19] 

## Martin et al.

[54] AQUEOUS COMPOSITION CONTAINING ALDEHYDE CONDENSATE AND USE THEREOF
[75] Inventors: Jeffrey 

### E. Martin, Columbus; Albert F. Vozella, Worthington; Golden F. Watts, Delaware; Edwin 

### R. Luckman, Columbus, all ofOhio
[73] Assignee: Ashland Oil, Inc., Ashland, Ky. [21] Appl. No.: 187,692
[22] Filed: Sep. 16, 1980
[51] Int. 0.3

....................... C08L 89/02; C08L 61/06 [52] U.S. CI.

.................................... 524/297; 524/296; 524/704; 524/502; 524/507; 524/510; 524/541; 524/361; 524/376; 524/378; 524/595 [58] Field of Search

......... 260/29.3, 29.4 R, 29.2 TN, 260/29.6 NR, 7; 525/58
[56] References Cited
U.S. PATENT DOCUMENTS
3,931,088 1/1976 Sakurada et al.

........... 260/29.6 RB [11]

[45] 

## 4,341,668

Jul. 

## 27, 1982

4,110,277 8/1978 Economy et al.

.................. 260/841 4,128,695 12/1978 Kikuchi et al.

.................. 428/424.8 4,179,427 12/1979 Gardikes

..................... 260/29.2 TN

FOREIGN PATENT DOCUMENTS

50-69138 6/1975 Japan. 50-69142 6/1975 Japan. 

### Primary Examiner-Theodore E. Pertilla 

### Attorney, Agent, orFirm-Pollock, Vande Sande & Priddy
[57] ABSTRACT

A composition containing a methylene donor, hydrophobic component containing an organic hydrophobic diluent and an isocyanate; and an aqueous component containing awatercompatiblealdehydecondensateand

use thereofas an impregnantorbonding agentfor cellulosic materials including paper, wood and cotton, and- /or fibrous materials including synthetic fibers, such as rayon and nylon.

41 Claims, No Drawings

### 1 

## 4,341,668

AQUEOUS COMPOSITION CONTAINING ALDEHYDE CONDENSATE AND USE THEREOF 

## 2 used without benefit in the case ofburning vapors unless large capital expenditures are made, wherein, heat generated from vapor burning is used to replace heat
costs encountered in papermaking and UB" staging the DESCRIPTION

1. Technical Field 5 saturated paper. Water solvent systems eliminating these capital investments are very attractive. The present invention is concerned with compositions containing a hydrophobic component containing

an isocyanate compound and an aqueous component containing an aldehyde condensate. Moreover, the 10 present invention is concerned with the use of such
water containing compositions for impregnating and bonding cellulosic materials such as paper, wood and cotton, and fibrous materials including synthetic fibers, such as nylon and rayon. 15

2. Background Art After paper is formed, it is usually saturated with a thermoset polymer composition such as a phenolicaldehyde condensate. Saturation places the resinous material in the interstices ofthe paper. Ithas been sug- 20 gested that phenolic-aldehyde condensates are chemically reactive with hydroxyl groups in cellulosics to provide strength and protection for the fibers. Since melamine and urea aldehyde condensates containmethylol groups similar to those in phenolic-aldehyde con- 25 densates, it is believed that melamine- and urea-formaldehyde condensates chemically react similarly to phenolic-aldehyde condensates. However, the final properties ofthe paper will differ.

Paper saturated with an aldehyde condensate is par- 30 tially heatcured or "B" stagedtoreactonly some ofthe methylol groupstogetherandtotie in partially withthe hydroxyl groups ofthe cellulosic papers; thereby, adding some physical strength to the paper. Grooving or corrugating is generally done at this point to provide 35 additional strength in final use. Thepaperis then rolled and shipped to the users, who pleat, fold or otherwise distort the flat rolled paper.

Pleatingis accomplishedbefore final cure. Ifthecure
were completed prior to pleating, the embrittlement of 40 the paper would cause fractures and subsequent loss of strength at the folds and filtration efficiency would be sacrificed or the filter could collapse in use.

Fuel costs and environmental considerations have prompted some end paper users to buy the paper in 45

more fully cured stages with the contained resins being modified to provide "pseudo-thermoplastics." These saturated papers require minimum heat to soften while pleating. Thisheating advancesthecureofthemodified resins minimally. Application of plastisols, which are 50 used as adhesives, ontheend caps offilters advancethe resins to a greater extent as theplastisols arecured with heat.

Filtermanufacturers that have perfected such system usage have substantially reduced their ownheating and 55 environmental compliance costs. The paper saturators, Another area where water solvent systems would be
very attractive is in the production of carpet backing and sound deadening insulation, such as from nonwovencottonfabrics. Forinstance, in theproductionof carpet backing such as for automobiles, where sound deadening and insulation from excess heat and/or cold is required, non-woven cellulosic fabric (e.g. cotton) is garnetted into a matusing phenolicpowderas theadhesivebetween thelayers ofthe garnet. Theuse ofa powder leaves much to be desired concerning handling of materials and waste. The mat is cured for about 30 seconds using elevated temperatures on both sides so thatthe matis easily handled. Themat is then subjected
to aheatmold/diecutmachinefor forming theproduct. At this stage, it is completely cured. The ability to employ a water system in place ofthe powder would be advantageous.

In addition, water systems which contain a hydrophobic component containing an isocyanate compound and an aqueous portion containing certain polymers reactivetherewithhavebeenpreviously suggested. The isocyanate component is present along with a hydrophobic solvent in order to retard the reaction between the isocyanate and aqueous component while the composition is in the liquid form. The hydrophobic solvent is employed to protect the isocyanate from premature reaction. Examples of some suggested compositions which employ such a system can be found in U.S. Pat. Nos. 3,931,088 and 4,128,695.

DESCRIPTION OF INVENTION
It is therefore an object of the present invention to provide an aqueous composition which can be used to impregnateandbondcellulosic and/orfibrous materials such as paper, wood, cotton, nylon, rayon and mixtures thereof, and which can be applied and cured with minimal energy requirements.

The present invention is concerned with a composition whichcomprises a compound capable ofproviding reactive methylene sites at elevated temperatures; a hydrophobic component containing an organic hydrophobic diluent and an isocyanate and an aqueous component containing a water compatible aldehyde condensate having free methylol groups.

The present invention is also concerned with substrates impregnated and/or bonded with the abovedefined composition and the process of coating cellulosic substrates and fibrous materials with the abovedefined composition.

BEST AND VARIOUS MODES FOR CARRYING OUT INVENTION Accordingtothepresent invention, the compositions include a hydrophobic component which contains an isocyanate. The isocyanate compound and/or polymer thereofis a molecule whichhas two ormore isocyanate
groups, such as toluene-diisocyanate, hydrogenated onthe otherhand, arebeing faced with using more fuel and emitting more volatile organic compounds (VOC) than previously encountered. Conversion to alcohol soluble, low emissions resins has cut smoke emissions 60 from phenol, but new regulations in most areas have brought about concern about alcohol emissions. Under certain VOC regulations, limits on a yearly basis have been set in some states for emissions for eachindividual manufacturing location. 65 toluene-diisocyanate, trimethylolpropane-tolueneThese VOCregulations force paper makers and saturators to either burn the alcohol vapors or consider non-organic solvent systems (water). Additional fuel is diisocyanate adduct, triphenylmethane-triisocyanate, methylene-bis-diphenylisocyanate, hydrogenated methylene-bis-diphenylisocyanate, hexamethylene-

## 3 4,341,668 

## 4 diisocyanate, xylene-diisocyanate, 4,4'-dicyclohexyl- or most preferably a phenolic-aldehyde condensate. methane-diisocyanate, and polymeric MDI (Le. poly- Mixtures of such aldehyde condensates can be emmeric methylenebisphenyl-diisocyanate) such as those ployed when desired. The aldehyde condensates are commercially available under the trade designations preferably heat reactive and are water soluble and/or PAPI and Mondur MR. 5 waterdilutable. The aldehyde condensates employed in

Moreover, a mixture of a polyisocyanate and a accordance with the present invention are methylol polyol, for example, a mixture ofpolyols, such as poly- containing materials with at least some available sites
ester or polyether with hydroxyl groups, and an excess filled as methylols and some reactive sites available for ofisocyanate can be employed ifdesired. subsequent crosslinking via methylene addition during

Furthermore, it is possible to employ a prepolymer 10 the pleating operation (heat applied). system, such as a prepolymer with NCO end groups, Examples ofphenols which can be employed in prepartially polymerized from a polyol and an excess of paring the phenolic-aldehyde condensates to be used in polyisocyanate, or a prepolymer with OH end groups, the present invention include phenol and substituted partially polymerized from an excess ofpolyol, mixing phenols. it with an excess ofone ofthe above-mentioned isocya- 15 Substituted phenols employed in the formation ofthe
nates. Mixtures of isocyanates can be employed when phenolic polymers include: alkyl-substituted phenols, desired. aryl-substituted phenols, cyclo-alkyl-substituted pheThehydrophobic diluent employed in the hydropho- nols, alkenyl-substituted phenols, alkoxy-substituted bic component according to the present invention pref- phenols, aryloxy-substituted phenols, hydroxy-suberably dissolves the isocyanate compound or polymer 20 stituted phenols, and halogen-substituted phenols, the and is liquid at normal room temperatures. The solubil- foregoing hydrocarbon substituents containing from 1 ity ofthe diluent in water and the solubility ofwater in to 26, and preferably from 1to 9 carbon atoms. Specific the diluent should preferably be below about 5 weight examples of suitable phenols include: phenol, resorcipercent at temperatures between 20· to 30· C. nol, catechol, hydroquinone, 2,6-xylenol, o-cresol, mSome typical examples ofsuitable hydrophobic dilu- 25 cresol, p-cresol, 3,5-xylenol, 3-4-xylenol, 2,3,4-trimethyl
ents include aliphatic, cycloaliphatic, or aromatic hy- phenol, 3-ethyl phenol, 3,5-diethyl phenol, p-tertbutyl drocarbons ormixtures thereofas the main component. phenol, 3,5-dibutyl phenol, p-amyl phenol, pSome hydrocarbons include toluene, xylene, benzene, cyclohexyl phenol, p-octyl phenol, 3,5-dicyclohexyl gasoline, kerosene, ligroin, tetralin, decalin, terpentine phenol, o-phenyl phenol, p-crotyl phenol, nonyl pheoil, pine oil, liquid paraffin, and alkyl benzene. In addi- 30 nol, p-phenyl phenol, 3,5-dimethoxy phenol, 3,4,5- tion, other diluents include halogenated hydrocarbons, trimethoxy phenol, p-ethoxy phenol, p-butoxy phenol, such as methylene chloride, l,l,l-trichloroethane, chlo- 3-methyl-4-methoxy phenol, and p-phenoxy phenol. In robenzene, chlorotoluene, bromobenzene, and chlori- addition, phenols containing multiple phenolic rings, natedparaffins; ketones, suchas methyl-isobutylketone, such as bis-phenol-A, can be employed. Mixtures of methyl-n-amyl ketone, methyl-n-hexyl ketone, ethyl-n- 35 phenols can be used when desired. butyl ketone, di-n-propyl ketone and acetophenone; The preferred aldehyde employed is formaldehyde. ethers, such as isopropyl ether, methylphenyl ether, Such can be in aqueous solution or any ofits low polyethyl-benzyl ether, and furan; lower aliphatic esters, meric forms, such as paraform or trioxane. The aldesuch as isopropyl acetate, amyl acetate, butyl acetate hydes preferably contain I to 8carbon atoms, examples and butyl propionate; phthalic acid diesters, such as 40 of which include acetaldehyde, propionaldehyde, budibutyl phthalate, dioctyl phthalate, and butylbenzyl tyraldehyde, benzaldehyde, furfural, 2-ethylhexanal, phthalate; oleic acid esters; adipic acid esters; azelaic ethylbutyraldehyde, heptaldehyde, pentaerythrose, glyacid esters, sebacic acid esters, stearic acid esters, ben- oxal, chloral, andthelike. Mixtures ofaldehydes canbe zoic acid esters, abietic acid esters, oxalic acid esters, used when desired. and phosphoric acid esters. Moreover, oils obtained 45 The preferred phenolic-aldehyde condensates emmainly from higher aliphatic acid esters, such as caster ployed according to the present invention are water oil, can be employed ifdesired. Mixtures ofdiluents can soluble and/or water dilutable and are obtained from be employed ifdesired. about 0.75 moles of aldehyde to about 3.3 moles of

It is important to note that the hydrophobic diluent aldehyde per mole ofphenolic compound, and preferashould not have amounts of active hydrogen groups, 50 bly atleast about 0.95 to about 3moles and mostprefersuch as carboxy-, hydroxy-, or amino-groups in the ably about 1.5 to about 2.5 moles ofaldehyde per mole molecule, such that upon mixing with the isocyanate ofphenolic compound. In addition, the preferred phecompoundorpolymerit readilyreactstherewithresult- nolic-aldehyde condensates are prepared under basic ing in a significant decrease in the concentration of conditionswhichemployabout0.25 to4%, andpreferaactive isocyanate groups available. 55 bly about 0.75 to 2.5% by weight of a basic material,

The isocyanate compound and/or polymer is em- such as a metallic oxide or hydroxide, ammonium hyployed in amounts ofabout I to about 99% by weight, droxide orbasicaminebasedupontheamountofphenol preferably about 10 to about 99% by weight, and most present. Examples ofsome suitable metallic oxides and preferably about 50toabout 90% byweightbasedupon hydroxides include alkali metal and alkaline earthmetal the total amount ofisocyanate and hydrophobicdiluent 60 oxides and hydroxides, such as sodium hydroxide, poemployed. tassium hydroxide and lithium hydroxide. Examples of

The term "protected isocyanate" when employed in some suitable basic amines include triethyl amine and thepresentspecificationrefers tothecombinationofthe triethanol amine. The most preferred phenolic-aldeisocyanate and hydrophobic diluent of the type dis- hyde polymers employed according to the present incussed hereinabove. 65 vention contain from about 3to about 5% by weight of

The aqueous component of the compositions ofthe free phenol and a pHofabout 8.5 to about9.0. Mixtures presentinventionincludes an aldehydecondensate. The ofphenolic-aldehyde polymers can be employed when aldehyde condensateis preferably a urea-, ormelamine- desired.

## 5 4,341,668 6 verted tohydroxyl groups for reaction with the isocyanate.

Examples of some suitable'ethylenically unsaturated

monomers to be employed in thepolymerbutwhich do A typical process for preparing the phenolic-aldehyde condensates include condensing at about 60°-105° C. until the aldehyde is substantially consumed. Itmay be desirable to carry out the process in the presence of casein such as in amounts from about0.5 to about 10% by weight based upon the weight of the phenol employed in the process.

The preferred phenolic-aldehyde condensates employed in the present invention have a pH of at least about 8 and most preferably at least about 8.3. The use of these preferred aldehyde condensates provide for compositions having a high degree ofstability and shelf life. 5 not contain groups reactive with theisocyanate include acrylate and methacrylatemonomers, suchas methylacrylate, ethylacrylate, butylacrylate, methylmethacrylate, ethylmethacrylate,butylmethacrylate, and 2-ethylhexyl acrylate; ethylene; propylene; styrene; methyl
10 styrene; divinyl benzone; butadiene; and vinyl esters such as vinylacetate, vinylpropionate, and vinyl versatate. Mixtures ofpolymers can be employed when desired.
The compositions of the present invention also includeacompoundcapableofprovidingreactivemethy- 15 lene sites at elevated temperatures. The methylene donors are essentially non-reactive at normal room temperatures but provide reactive methylene groups at elevated temperatures such as at about 135° C. and above. Examples of some specific methylene donors 20 include hexamethylene tetraamine and trimethylol 

### nitromethane. Mixtures ofmethylene donors can be employed whendesired. Themethylenedonors arepreferably water soluble or water compatible and present in 25 the aqueous component of the composition. The
amount ofmethylene donor is usually about 1to about 20% byweight and preferably about 5to about 10% by weight based upon the total amount of aldehyde condensate present in the composition. 30

The aqueous component of the compositions ofthe present invention can also contain polymers in addition
to the aldehyde condensate. This additional polymer is
water soluble orwaterdispersible. The additionalpolymer can be non-reactive or preferably contain at least 35

onegroupwhichis reactivewiththeisocyanate, suchas reactive hydrogen groups including hydroxyl, carboxyl, amine and amide groups. Examples ofsome suitable polymers containing groups reactive with the isocyanate are synthetic water dispersible polyesters ob- 40 tained from polyhydric alcohols, such as propylene glycol and polypropylene glycol and polycarboxylic acid such as adipic acid; and homopolymers or copolymers (from two or more monomers) from monomers containing ethylenically unsaturated groups. 'For in- 45 stance, those polymers suggested in 

## u.s. Pat. No. 3,931,088 are quite suitable for the purposes ofthepresent invention.

Examples ofsome suitable ethylenically unsaturated

monomers with groups reactive with isocyanates to be 50 employed in the polymer include dimethylaminoethylmethacrylate, 2-hydroxyethylacrylate, 2-hydroxyethylmethacrylate, hydroxypropylmethacrylate, ethyleneglycoldimethacrylate, hydroxypropylacrylate, Nisobutoxy methylacrylamide, acrylamide, methacryl- 55 amide, allyl alcohol, acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, and maleic anhydride. In addition, examples of some suitable copolymers containing N-methylol functional derivative of an allyl carbamate etherified with a CI-Cg alcohol 60

can be found in

## u.s. Pat. No. 3,941,735 to Lindemann.

Thereactive groupscanbeprovidedin themonomer and/or the polymerby treatment subsequent to and/or
concurrent with the polymerization ofthe monomers. For instance, polymers from vinyl acetate can be 65 treated by saponification to provide reactive hydroxyl
groups to provide polyvinyl alcohol. Also, the glycidylacrylate and glycidylmethacrylate can be conThe polymers reactive with the isocyanate generally contain an average ofat least about two reactive functionalities per polymer chain.

The presence of the additional polymer and especially the polymers which contain at least one group reactive with the isocyanate provide for enhanced physical strength characteristics. Those compositions which contain an additional polymer which contain at least one group reactive with the isocyanate are preferred.

The term "polymer component which contains
groups reactive with the isocyanate" or similar terms referstotheentire additionalpolymercomponentofthe
aqueous phase wherein at least one of the polymers contains atleastonegroupreactivewiththeisocyanate. Accordingly, said term canencompass a mixture which also includes polymers which do not have groups reactive with the isocyanate.

The compositions of the present invention can include auxiliary agents such as compounds known to catalyzeisocyanate reactionsincommonurethanereactions. Examples of urethane catalysts include amines, divalent metal salts, alkali and alkaline earth oxides and hydroxides. Thepreferred urethane catalysts employed according to the present invention are tertiary amines. Those compositions which contain an additional polymer containing at least one group reactive with the isocyanate and a tertiary amine have enhanced stability and shelf-life when compared to such compositions which do not contain a tertiary amine.

Thetertiary amineswhichareemployedaccordingto

a preferred aspect of the -present invention are those which are generally deemed to be catalysts for isocyanate reactions, and preferably tertiary amines including the alkanol amines and alkyl arriines whereinthealkanol and/or alkyl groups generally each contain 1 to 5 carbon atoms.

The amines generally have,up to about 20 carbon
atoms. Examples of suitable amines include trialkyl amines suchas trimethylamine andtriethylamine; triethanolamine; dimethylethanolamine; diethylenetriamine; tetramethyl butane diamine; N-methyldipropylene triamine; N-diethylamino acetic acid; methylamino propionic acid; pyridine; substituted pyridines; N-alkyl morpholine compounds such as N-methyl morpholine; other substituted morpholine compounds such as Nacetyl morpholine and4,4'-dithiomorpholine; quiniline; isoquiniline; tetra-methylguanidine; cyclohexyl dimethylamine; and dimethyl aniline.

The compositions ofthe present invention generally contain about 5to about 97.5% byweight, and preferably about 10 to about 60% by weight ofthe aldehyde condensate; about 2to about75%byweight, preferably about 5% to about40% byweight and more preferably about 5to about 25% byweight oftheisocyanate com-

## 7 4,341,668 

## 8 poundand/orprepolymer. Theabove amounts ofmaterials are based upon the total ofthe aldehyde condensate, isocyanate, and methylene donor present in the composition. Theamountofmethylenedonoris about 1
to about 20%by weight andpreferably about 5toabout 5 10% by weight based upon the aldehyde condensate.

With respect to those compositions of the present invention which contain one or more ofthe above-discussed additional polymers, such, in addition to the above-discussed amounts ofmethylene donor, generally 10 contain from about 5 to about 50% by weight, and preferably about 10 to about 30% by weight of the aldehyde condensate; about 2 to about 75% by weight, preferably about 5 to about 40% by weight, and more preferably about 5to about 25%byweightoftheisocy- 15
anate compound and/orprepolymer; about 25 to about 93% by weight, preferably about 50 to about 85% by weight, and more preferably about 70 to about 85% by weight of the above-discussed polymer in addition to the aldehyde condensate; and when present from about 20 0.1 to about 10% by weight, preferably about 0.1 to about 4% by weight, and more preferably about 0.1 to about 2% by weight ofthe tertiary amine. The above
amounts of materials are based upon the total of the aldehyde condensate, isocyanate, additional polymer, 25 and tertiary amine present in the composition.

The compositions ofthe present invention generally contain from about 10 to about 74% byvolume ofnonvolatiles, preferably about 30 to about 60% by volume, and more preferably about 35 to about 55% by volume 30 ofnonvolatiles based upon thetotal volume ofthecomposition. The isocyanate compound and/or polymer is employed in amounts of about 1 to about 99% by weight, preferably about 10 to about 90% by weight, and more preferably about 50 to about 90% by weight 35 based upon the total amount ofisocyanate and hydrophobic diluent employed in the composition. As apparent, the remainder ofthe composition after taking into
account the amount ofnonvolatile component and the
amount oforganic diluent is the water. 40

In addition, the compositions can include auxiliary agents such as surface-active agents, water soluble oligomers, and fillers. The surface-active agent can be introduced to the compositions due to its use in the preparation ofany ofthe polymers employed. The sur- 45 face active agents can be anionic, cationic or nonionic surface active agents. Examples ofsome anionic surfactants include carboxylic acid salts such as salts of aliphatic carboxylic acids; alkyl sulfates and sulfonates; alkyl benzene sulfonates; alkyl naphthalene sulfonates; 50 lignin sulfonates; and alkyl benzene sulfonates, alkyl naphthalene sulfonates, and the like; phosphonic ester salts such as phosphonic acid esters of higher fatty acids, and the like. Theconcentration ofthe surface-active agent when employed is usually about 0.1 to about 55 10 weight percent, and more preferably about 0.2·to about 5 weight percent based upon the weight of the polymers presentin the aqueous componentofthe composition.

Suitable fillers include organic substances such as pO wood powder and powder of walnut shell, as well as inorganic substances, such as clay, kaolin, silica, calcium carbonate, and talc.

The amount offiller, ifemployed, is generally about 10 to about 50 volume percent based upon the total 65

nonvolatiles ofthe composition.

The preferred compositions ofthe present invention

are substantially, ifnot completely free from acid catalysts. The aqueous component can be a solution, emulsion, or suspension, or combination thereof.

Thecompositions ofthe present invention arepreferably prepared by adding the methylene donor prior to the incorporation ofthe isocyanate portion ofthe composition. However, any sequence of addition of the components can be carried out. Also, the compositions

are preferably prepared by adding the amine when present prior to the incorporation of the isocyanate portion ofthe composition. When the composition contains one or more of said additional polymers having groups reactive with the isocyanate, for improved stability characteristics, the preferred method ofadmixing provides for improved stability characteristics when said additionalpolymerhaving groups reactivewiththe isocyanateis present andincludesadmixingthepolymer reactive with the isocyanate followed by the amine followed by the aldehyde condensate, followed by the methylene donor and then the isocyanate portion or admixing the polymer reactive with the isocyanate to which is added the aldehyde condensate followed by the amine andmethylenedonorand thentheisocyanate portion.

In addition, the compositions should be prepared by low speed or low shear mixing conditions, since high shear type mixing tends to shorten the pot life of the composition. It has been noted that the finer particle dispersions result in shorter pot life. Accordingly, ·a mild agitation is normally employed to form the mixtures ofthe present invention.

Thecompositions canbe subjected to an initialpartial

cure treatment which is usually carried out at room temperature to about 121° C. for about 5 minutes to about 24 hours. The composition because of the presence ofthe methylene donor can be post cured such as byheatingat 135° C. to about 232° C. for about 1minute
to about 15 minutes. The time and temperature up to above cure treatments are inversely related. Thatis, as the temperature increases, the time needed for cure decreases and vice versa.

The compositions ofthe present invention are particularly suitable for bonding and impregnating cellulosic materials and/orfibrous materials such as paperincluding filter papers, such as oil filter paper, industrial air filter paper and railroad filter paper; wood; cotton, including waste cotton fibers; nylon; and rayon.

Thefollowing non-limiting examples arepresented to further illustrate the present invention wherein all parts

are by weight unless the contrary is stated.

EXAMPLE 1
To about 100 parts by weight ofa polymer aqueous emulsion of about 35% solids are added with a slow speed mixing about 6.8 parts by weight ofa heat reactive water dispersible aqueous phenol-formaldehyde polymer with 50% solids; about 1 part by weight of triethylamine, about 0.3 parts by weight ofhexamethylene-tetraamine, and about 3.4 parts by weight of a protective polyisocyanate containing about 75% by weight ofa polymericmethylene diphenyl diisocyanate (MDI), about 12.5% by weight of toluene, and about 12.5% byweight ofdibutylphthalate. The aqueous polymer emulsion is obtained from· about 43.04 parts by weight of Vinol 523, about 9.56 parts by weight of Vinol 425, about 693.08 parts by weight ofAirflex 400, about 0.48 parts by weight ofDowcil 75, and sufficient
water to provide a solids content ofabout 34%. Vinol 523 is a polyvinyl alcohol commercially available from

### 9 

### 4,341,668

Air Productsand Chemicals, Inc., and, accordingtothe manufacturer, is about 87 to about 89% hydrolyzed, has

a pH ofabout 5to 7 as measured in a 4% aqueous solution, and a viscosity ofabout 21 to about 25 centipoise

as measured in a 4% aqueous solution at 20° C. Vinol 5 425 is available from Air Products and Chemicals, Inc. and, according to the manufacturer, is a polyvinyl aJcohoI hydrolyzed to about 95.5 to 96.5%, has a pH of about 5to 7 as measured in a 4% aqueous solution, and

a viscosity ofabout 26 to 30 centipoise as measured in a 10 4% aqueous solution at 20° C. Airflex 400 is commercially available from Air Products and Chemicals, Inc. and is an aqueous solution emulsion of a co-polymer ethylene and vinyl acetate and, according to the manufacturer, has a minimum solids ofabout 55%, a Brook- 15 field viscosity at 60 rpm and 77° F. of about 1400 to about 2000 centipoise, and a Brookfield viscosity at 20 rpm and 77° F. ofabout 1900 to about 2800 centipoise,

a pHofabout4.0 to about 5.0, andcontainas protective colloid partially acetylated polyvinyl alcohol. A further 20 discussion ofAirflex 400 can be found in a publication from Air Products and Chemicals, Inc. entitled "Air Flex 400 Base for Adhesives", Bulletin 151-919, disclosure of which is incorporated herein by reference. Dowcil 75 is available from the Dow Chemical Com- 25 pany and, according to the manufacturer, is 1-(3- chloroallyl)-3,5,7-triaza-1-azoniaadamantane chloride containinga sodiumbicarbonate stabilizer. Dowcil75 is

a preservative used in adhesives.

The phenol-formaldehyde condensate is prepared 30 from formaldehyde and phenol in a mole ratio ofabout 1.8:1; employing about 35.2 parts by weight ofphenol, about 2.1 parts by weight of 50% aqueous sodium hydroxide, about 15.5 parts by weight ofwater, aDout 3.4 partsbyweightmethanol, about41.7 partsbyweightof 35 50% formaldehyde, and about 0.09 parts by weight of 29% aqueous ammonia at a pH ofabout 8.5. The phenol-formaldehyde has about 4% free phenol.

Automotive oil filter paper is treated with the above composition to provide about 18 to 22% polymer 40 pickup when cured at about 121° C. for about 15 minutes. The treated paperis partially curedbyheating for 5 minutes at about 177° C. The treated paper is then conditionedfor 4hours atabout77° 

### F. and 50% relative humidity before being tested. The tests performed are 45 for Mullen burst strength, tensile strength, and Gurley stiffness values. TheMullen burst strengthis about 43.0 psi, the tensile strength about 27.4 Ibs/inch, and the Gurley stiffness MD (machine direction) about4445 mg and Gurley stiffness XD (cross direction) about 2756 50 mg.

Prior to post curing, the Mullen burst strength is about 44.6 psi, the tensile strength about 26.4 Ibs/inch, the Gurley stiffness MD is about 3512 mg and the Gurley stiffnessXDis about2400 mg. After68 hours at200° 55 F. in lOW-40W multigrade oil, the Mullen burst strength is 40.1 psi, the tensile strength is about 25 Ibs/inch, the Gurleystiffness MDis about 5218 mg, and the Gurley stiffness XD is about 3256 mg.
COMPARISON EXAMPLE 2 Example 1 is repeated except that the composition does notcontain amethylene donor, and accordingly, is
not subjected to post curing. TheMullenburst strength 60

is about 44.5 psi, the tensile strength is about 28.8 65 1bs/inch, the Gurley stiffness MD about 2845 mg and the Gurley stiffness XD about 1556 mg. After 68 hours
at 250° F. in lOW-40W multigrade oil, the Mullenburst 

## 10 strength is 42.5 psi, the tensile strength is 27.5 Ibs/inch, the Gurley stiffness MD is 2534 mg and the Gurley stiffness XD is 1512 mg.

A comparison of Examples 1 and 2 illustratys the significant improvement in stiffness achieved by employing a methylene donor which renders the treated
paperpractical for use as an oil filter. Theburst strength and tensile strength when employing the methylene donor were only reduced slightly.

EXAMPLE 3

To about 100 parts by weight ofa polymer aqueous emulsion obtained by admixing about 181.5 parts of water, about 3.5 partsofhexametaphosphate; about 1.35 partsoftributylphosphate; about 3.10partsof80 micron calcium carbonate (Gamma sphere 80); about 19 parts ofa 15% aqueous polyvinyl alcohol available under the trade designation PBA-EST; about 61 parts of a heatreactive water-dispersible aqueous phenol-formaldehyde polymer with 50% solids; about 396 parts of a noncarboxylated butadiene-styrene polymeric latex available under the trade designation Dow SBR Latex XD 30485; about 13.2partsoftoluene; about 1.2 partsof Dowacil 75; and about 5 parts of a hydroxymethyl cellulose available under the trade designation Carbopolare added about 5partsofa 50% aqueous solution of hexamethylenetetraamine and about 20 parts of a protective polyisocyanate containing about 75% by weight ofa polymeric methylene diphenyl diisocyanate (MDI), about 12.5% by weight of toluene, and about 12.5% by weight ofdibutylphthalate. The PBA-ESTis similar to Vinol 425 employed in Examples 1 and 2 above and is a polyvinyl alcohol hydrolyzed to about 95.5 to 96.5%, has a pH ofabout 5 to 7 as measured in

a 4% aqueous solution, and a viscosity ofabout 26 to 30 centipoise as measured in a 4% aqueous solution at 20° C.Dowcil 75 is available from the DowChemical Company and, according to the manufacturer, is 1-(3- chloroallyl)-3,5,7-triaza-1-azoniaadamantane chloride containing a sodiumbicarbonate stabilizer. Dowcil75 is

a preservative used in adhesives.

The phenol-formaldehyde condensate is prepared from formaldehyde and phenol in a mole ratio ofabout 1.8:1; employing about 35.2 parts by weight ofphenol, about 2.1 parts by weight of 50% aqueous sodium hydroxide, about 15.5 parts by weight ofwater, about 3.4 partsbyweightmethanol, about41.7partsbyweightof 50% formaldehyde, and about 0.9 parts by weight of 29% aqueous ammonia at a pH ofabout 8.5. The phenol-formaldehyde has about 5% free phenol.

The composition is applied to one surface at 60

. Ibs/100 sq. ft. via brushing and two surfaces of two

pieces of Ponderosa Pine wood are bonded together under 125-150psi for 16 hours. Thecomposition is then postcuredfor 10minutes at325° F.Thelaminateis then subjected to 4 hours boiling water and dried overnight in a forced air oven at 60° C. It is then subjected to boiling water for another 4 hours.

Then it is cooled with ambient water and tested wet to determine tensile-shear strength, according to ASTM 3110. The tensile-shear strength is 376 psi with 35% wood failure.

COMPARISON EXAMPLE 4 Example 3 is repeated except that the composition does notcontaina methylenedonorand, accordingly, is
not subjected to post curing.

## 4,341,668 

## 12 

## 11 When subjected to the boil dry testing according to ASTM 3110, thetensile-strength is 328 with 25% wood failure.

We claim: 1. A composition comprising a compound capable of 5 providing reactive methylene sites at elevated temperature ofabout 135 0 C. and above; a hydrophobiccomponent containing an organic hydrophobic diluent and an isocyanate; and an aqueous component containing a water soluble phenolic-aldehyde condensate having 10 free methylol groups and a pH ofat least about 8 and being obtained from about 0.75 to about 3.3 moles of aldehyde per mole ofphenolic compound.

2. The composition of claim 1 wherein said compound capable ofproviding reactive methylene sites is 15 hexamethylene tetraamine ortrimethylol nitromethane.

3. The composition of claim 1 wherein said compound capable ofproviding reactive methylene sites is hexamethylene tetraamine.

4. The composition of claim 1 wherein the aqueous 20 component further includes a polymer in addition to said aldehyde condensate.

5. The composition ofclaim 4 wherein said polymer in addition to said aldehyde condensate containsgroups reactive with said isocyanate. 25

6. Thecomposition ofclaim 1which further contains

a tertiary amine.

7. The composition of claim 1 wherein said isocyanate compound contains at least twoisocyanate groups.

8. The composition of claim 7 wherein said isocya- 30 nate is polymeric methylene bisphenyl diisocyanate.

9. The composition of claim 1 wherein said hydrophobic diluent is selected from the group of aliphatic hydrocarbons, aromatic hydrocarbons, cycloaliphatic hydrocarbons, halogenated hydrocarbons, ketones, 35 ethers and esters.

10. The composition ofclaim 9 wherein said hydrophobic solvent is an aliphatic, cycloaliphatic or aromatic hydrocarbon.

11. The composition ofclaim 9 wherein said hydro- 40 phobic solvent is an aromatic hydrocarbon.

12. The composition ofclaim 9 wherein the hydrophobic solvent is toluene.

13. The composition ofclaim 9 wherein said hydrophobic solvent is a diester ofphthalic acid. 45

14. The composition ofclaim 9 wherein said hydrophobic solvent is dibutyl phthalate.

15. The composition of claim 1 wherein the isocyanateis employed in amounts ofabout 1to about 99% by weight based upon the total amount ofisocyanate and 50 hydrophobic diluent.

16. The composition of claim 1 wherein the isocyanate is employed in amounts ofabout 10 to about 90% 21. Thecomposition ofclaim 1wherein the phenolicaldehydecondensateis obtained from about 1.5 to about 2.5 moles ofaldehyde per mole ofphenolic compound.

22. The composition ofclaim 1 wherein said phenolic-aldehyde condensate is prepared under basic conditions employing about 0.25 to about 4% by weight ofa basic material based upon the amount ofphenolic compound.

23. The composition ofclaim 1 wherein said phenolic-aldehyde condensate is prepared under basic conditions in the presence of about 0.75 to about 2.5% by weight of a basic material based upon the amount of phenolic compound.

24. The composition ofclaim 1 wherein said phenolic-aldehydecondensatecontainsabout 3to about 5%by weight offree phenolic compound.

25. The composition ofclaim 1 wherein said phenolic-aldehyde condensate is a phenol-formaldehyde condensate prepared in the presence of casein at a pH of about 8.5 to about 9.0.

26. The composition ofclaim 25 wherein the amount of casein present is from about 0.5 to about 10% by weightbasedupontheweightofthephenol andformaldehyde.

27. The.composition ofclaim 5 wherein the aldehyde condensate is employed in an amount of about 5 to about 50% by weight; saidisocyanateis employed in an amount of about 2 to about 75% by weight; and the polymer which contains groups reactive with said isocyanate is employed in an amount ofabout 25 to about 90% by weight wherein the above amounts are based
upon the total ofaldehyde condensate, isocyanate, and the polymer which contains groups reactive with said isocyanate in the composition.

28. The composition ofclaim 5 which contains from about 0.1 to about 10% by weight ofa tertiary amine based upon the total of aldehyde condensate, isocyanate, the polymer which contains groups reactive with said isocyanate and amine.

29. Thecomposition ofclaim 5wherein the aldehyde condensate is employed in an amount of about 10 to about 30% byweight, said isocyanate is employed in an amount ofabout 5 to about 

### 40% by weight; said polymer component which contains groups reactive with said isocyanate is employed in an amount ofabout 50 to about 85% by weight wherein the above amounts are based upon the total ofthe phenolic-aldehyde condensate, isocyanate, and polymerreactive with said isocyanate in the composition.

30. The composition of claim 29 which includes a tertiary amineofabout0.1 to about4%byweightbased
upon the total of said phenolic-aldehyde condensate, said isocyanate, said amine, and said polymer compoby weight based upon the total amount of isocyanate and hydrophobic diluent.

17. The composition of claim 1 wherein the isocyanate is employed in amounts ofabout 50 to about 90% 55 nent which contains groups reactive with said isocyanate.

by weight based upon the total amount of isocyanate and hydrophobic diluent.

18. Thecomposition ofclaim 6 wherein said amine is 60 triethylamine.

19. The composition ofclaim 1 wherein said phenolic-aldehyde condensate is a phenol-formaldehyde condensate.

20. Thecomposition ofclaim 1whereinthephenolic- 65 aldehyde condensate is obtained from about 0.95 to about 3 moles of aldehyde per mole ofphenolic compound. 31. The composition of claim 1, 27, 28, 29 or 30 wherein the amount ofsaid compound capable ofproviding reactive methylene sites is about 1to about 20% ofweight based upon the weight ofsaid aldehyde condensate.

32. The composition ofclaim 31 wherein the amount ofsaid compound capable ofprovidingreactive methylene sites is about 5to about 10% byweightbased upon the weight ofsaid aldehyde condensate.

33. The composition of claim 1 wherein the total nonvolatile content is about 10 to about 74% by volume.

## 13 4,341,668 

## 14 34. The composition of claim 1 wherein the total nonvolatile content is about 30 to about 60% by volume. isocyanate have an average ofat least about two reactive functionalities per polymer chain.

35. The composition of claim 1 wherein the total nonvolatile content is about 35 to about 55% by vol- 5 39. The composition of claim 4 or 5 which further contains about 0.1 

### to about 10 weight percent ofa surface-active agent based upon the weight of the polymers present in theaqueous componentofthecomposition. ume.

36. The composition of claim 1 wherein the pH of said phenolic-aldehyde condensate is at least about 8.3.

37. The composition of claim 5 which said groups reactive with said isocyanate are selected from the group ofhydroxyl, carboxyl, amine, amide or mixtures thereof.

38. Thecomposition ofclaim 5 wherein said polymer component which contains groups reactive with said 40. The composition of claim 1 which further in10 cludes about 10 to about 50 volume percent ofa solid filler based upon the nonvolatiles ofthe composition.

41. Thecomposition ofclaim 1whichis substantially free from acid catalysts. 

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