CA1207097A - Composites made from thermosetting compositions containing hemiformals of phenol - Google Patents

Abstract

COMPOSITIONS CONTAINING HEMIFORMALS OF PHENOL
ABSTRACT

There are described composites containing from about 20 to about 70 weight percent of a reinforcing material, such as glass, carbon, graphite, or aromatic polyamide fiber, and from about 30 to about 80 weight percent of a thermosetting composition which contains hemiformals of phenol and methylolated phenol and a polymer miscible with the hemiformal.
S P E C I F I C A T I O N

Description

~7(~97 This invention is directed to reinorced composites made from ~ thermosetting composition containing hemiformals of phenol and a miscible polymer. These composite have~excellent physical properties and show excellent flame resistance.
Until recently, liquid hemiformal compositions of phenol have been generally unknown although there has been speculation in the literature about hemiformals of phenol for some time.
Illustrative of such literature is WalXer, FORMALDEHYDE, 3rd Edition, published by Reinhold, Publishing Corporation, New York, (1964), pages 305, 306 wherein the following is stated:
"In the absence of added catalysts, anhydrous formaldehyde and paraformaldehyde dissolve in molten phenol without apparent reaction to give clear, colorless solutions which smell strongly of formaldehyde. In such solutions, it is probable that some solvation takes place and hemiformals, C6 50CH20H, C6H50CH20CH20H, etc., are present. However, studies of formaldehyde polymers have demonstrated that phenol is a solvent for these compounds and the majority of the dissolved formaldehyde in phenolic sol~tions may be in the polymerized state. Studies by Fitgerald and Martin involving the measurement of hydroxyl ion concentrations in dilute, alkaline, aqueous ormaldehyde in the presence and absence of the sodium phenolate of mesitol indicate that hemiformal 44. Fi~zgerald, J.S., Martin, R.J.L., Australian J.
Chem. 8, 194-214 (1955) ~2~7097 concentrations are too 6mall to be measured in this way. However, in our opinion hemiformal formation with a hindered phenol, such as mesitol, would be similar to hemiformal formation with tertiary butyl S alcohol which does not show any appreciable solvation of formaldehyde. There is a definite analogy of nonaqueous phenol formaldehyde ~olutions to 601utions of formaldehyde in alcohols and other polar solvents. According to Reychler , a small percentage of sodium phenolate catalyzes the solution of linear formaldehyde polymers in phenol, just as sodium alcoh~lates catalyze solution in methanol, ethanol, and other alcohols. That hemiformals are produced is also indicated by the isolation of methyl phenyl formal from an acid-catalyzed reaction of phenol with formaldehyde solution containing methanol CH20(aq) CH30H
~ OH > ~ OC~20H >

~ OCH20 H3 H20 One of the difficulties with the conclusion which is raised in the Walker article is that the hemiformal is produced from an acid-catalyzed reaction of phenol with formaldehyde solution containing methanol. It is notoriously well known that acids act to catalyze the reaction of phenol 102. Reychler, A., Bull. Sot. Chim. t40) 1, 1189-95 (1907), Chem Abs. 2 p 1266 (1908) 20. Breslauer, J., Pictet, A. Berichte, 40 3785 (1907) 1~70gt~
with formaldehyde to effect normal alkylation of phenol by formaldehyde to produce the phenolic resins. ~hus what is 6een by Walker a~ a 6uggestion of the existence of the hemiformal may be nothing more than the known reaction between methanol and formaldehyde in the presence of an acid catalyst to form a product which is subsequently reacted with phenol to yield the ether product which is characterized as the final product of the reaction.
Actually a reaction between formaldehyde and phenol to produce the hemiformal wouId have yielded an equilibrium reaction and this is totally absent from the reaction characterized by Walker; suggesting again that in the theoretical reaction disclosed by Walker the formaldehyde is first stabilized with methanol and then the prod~ct is reacted with phenol.
Bakeland and Bender in an article in "Industrial and Engineering Chemistry" Volume 17, No. 3, pages 225 -237 (1925) make the following statements concerning the formation o~ a theoretical hemiformal of phenol:
"The phenol first unites directly with the aldehyde to form a mixed ether-alcohol compound (XXXIII), and the resulting ether gro~p very rapidly rearranges to the phenol.
R R\ /OH Rearranges R jOH
~)~ = O t- HOC6H5 C > C
R' R' OC6H5 rapidly R C6H4H
(XXXIII) (XXXIV) ~2~0~7 C6H50H ~ R CC6H5 Sometimes rearrange; R /C6H40~

R C6~40H ~lowly R C6H40H "
(XXXV) ~XXXVI) Thus, Bakeland and Bender clearly indicate that if the hemiformal exists it i~ at best a transitory material which is unstable under the conditions at which it was produced and is a theoretical composition constitutinq an intermediary in the generation cf phenolic resins.
Strupinskaya et al. in Plast. ~ssy 1968 ~12), at pp 18-20 described the preparation of a product by the absorbtion of formaldehyde into molten phenol at a ~ormaldehyde to phenol ratio of 3:10. This corresponds to a ~ormaldehyde to phenol mole ratio of 0.94:1. The source of formaldehyde was a converter gas ~tream containing about 10~
methanol and analysis of the product showed it to contain up to 8~ methanol. The presence of methanol suggests that this reference refers to a ~ethanol ~tabilized product similar to that disclosed in Walker, cited above, wherein formaldehyde reacts with methanol and subsequently reacts with phenol to form the ether product. The low formalde~yde to phenol ratio also indicates that hemiformals havins average formaldehyde to phenol ratios higher than 1:1 would likely not have been formed by their method.
In Belgium Patent 667,360 issued on November 16, 1965 to Chemische Werke Huels A. G. is disclosed the treatment of various - hydroxy-compounds, inclùding phenol, with monomeric 9~

formaldehyde at a formaldehyde to phenol ratio of 1:1. The low formaldehyde to phenol ratio would indicate that any hemlformal formed would probably have no more than an average of one formaldehyde moiety in the hemiformal chain structure. As disclosed in Bakeland and Bender, cited above, hemiformals are known in the art as transitory or unstable species and would be expected by one of ordinary skill to be increasingly unstable as the length of the hemiformal chaln increases. It would, therefore, be expected that additional formaldehyde added in the Huels process would react with the pllenol at another site on the aromatic ring, such as at the para or ortho-position, rather than Eorming hemiformals with higher formaldehyde to phenol ratios. A person normally skilled in the art would normally expect that hemiformal compositions having formaldehyde to phenol ratios greater than 1:1, wherein hemiformal chains having more than one formaldehyde moiety are formed, would be unstable, forming other phenol-formaldehyde resinous products or dlsassociating to form free formaldehyde.

~2~ 7 ~ h~ flr-t tl~ re ~ h~ n ~t~bll~lhod ~t b~f~ a o~ ~nol ~ ~ ylDl-tod ~h~nol ~l~V~ boen ~a~2 ~ich hJY~ r~co~,n~2~d ~t~bll~y ~r~ â~ol~bl~, an~ c~n ~e utlll~ ln the ~omlst~on o~
5 a ~ar~t~ ~f a~6duc~ a~t~cul~rlg ~h~nol-~nrm~1~2hyd~ r~n~ n r:~n~ n P~t~nt ~ppl~c~t~n, ~orlJl llo. 4~17t'~4~ y Cov~e2, ~rc~e an~
t:ho~ flld D~c~mber 15~ 1982 and U.S. I'atent No.
4,~ 3,129, ~h~roln llqul~ heml~orm~l c~po~l~lon~ of 10 ph~nol pr~fl~ y ~he roQctlon of i~orDI~ldehyde and phQn~l ~r~ clo~o~. .
The ho~if~ there~n ~l~clo~d ~re h~DIiformals o~ ~henol, nd hemlfo~ o~
methylol-t~d ~henol haYlng the fo~ul~s;
(I) ~(CH2) N

(II) ~pH
r ~ tcH 0(CH 0 ) H~

2 2 lb c ltCH OH) 2 d (ITI~ Q~CW 0 ~ 2 n -b~ ~CH 0~CH 0) Jl) ~CH ON) 2 d ~her~ln ~ o~lt~ nwl~ber o~ llt 1~15t 1, ~r~'Dly ~ ~alue o~ 1 to ~ut 5, olo~t ~r2fcr~bly ~ ~lu~ of ~bout a.2 to 2.5; ~ ~ 1 to ~bout 5, D-ï2824-~

~Z~71)97 l to about ~, d is 0 to about 2, and the sum of c and d is at least 1 and no greater than 3.
Al~o disclosed are mixtures of the above hemiformals and also mixtures of any of the above with hemiformals of substituted phenols or oil modified phenols. As disclosed in the above cited applications, these hemiformals are of low viscosity and are stable at temperatures between about 35C and 55C.
These hemiformal compositions are very reactive in the the presence oE an acid or base catalyst typically use in aldehyde-phenol polymerization reactions and are useEul in forming phenolic-type resinous products.
In United States Patent No. 4,433,119 is described the use of the above-described hemiformal compositions to form solutions of thermoset compositions with other polymeric materials, such as phenol-formaldehyde resole and novolac resins, ~romatic polyester, polycarbonate, unsaturated polyester, poly(aryl ether), urea-formaldehyde, and melamine-formaldehyde polymers to form thermosetting compos~tions. These solutions are stable, and are of low viscosity. It has now been found that these thermosetting compositions are par~icularly useful in ~2~3~0~7 the formation of reinforced composites. They are p~rticularly useEul in molding techniques such as liquid injection molding (LIM), reaction injectlon molding (RIM), hydraJecting, and resin transfer molding (RTM) wherein liquid thermosetting compositions are injected directly into a mold where they are cured; resulting formation of a fabricated part.
These thermosetting compositions are also adaptable to the sheet molding compound method ~SCM), wherein a resin, reinforcing fiber and other additives are mixed under low shear conditions and the resulting viscous mixture cured to non-tacky sheets. Final cure to finished parts is then carried out in a mold.
It has been found that these solutions can be used to form composites having a relatively high content of reinforcing material and having excellent physlcal properties and flame resistance. In most thermosetting compositions, particularly of the phenolic type, there has been a limitation of the amount of reinforcing fiber that can be added to ~2~'~'0~

form composites. This is due in large part to the high viscosity of the~e compositions, many of which are nearly solid, which necessi~ates high s~ear mixing with the reinforcing material and injection under high shear conditions into the mold. This results in significant attrition of the reinforcing material, thus lowering the strength of the final composite. The high viscosity also prevents 6ufficient wetting of the fiber and mixing with the fiber. This results in composites of poor physical properties and ~epara~ion of the composites at the site of the fibers. For this reason fiber content of such composites has generally been limited to about 40 weight percent or below. Solvents have been used to lower the viscosity, but these upon cure of the resin volatilize which causes formation of voids in the composite and leads to excessive mold pressures.
Since it is desirable to have high reinforcing fiber content in the composites, to obtain the superior physical properties obtainable thereby, a phenolic resin having a low viscosity that can be used to ~orm 6uch high fiber content composites without encountering the problems discussed above, would be very desirable.
The liquid thermosetting compositions disclosed above, containing hemiformals of phenol, are of low viscosity, thus a high shear mixing step is unnecessary to incorporate the reinforcing material into the co~position. The reinforcing material may optionally be placed directly in the mold before injection of the thermosetting composition. The composition is of low enough viscosity such that the reinforcing material is - 10 -~26~'~097 quickly wetted and intimately incorporated in the thermosetting composition. Upon cure, the resulting composite, therefore, has superior physical properties.
Generally, molding techniques such as liquid in~ection molding and sheet molding compounds have been restricted to polyesters due to the difficulties, described above, that occur when using most other thermosetting resins. Because of the excellent physical properties and flame resistance of phenolics, a phenolic-type resin useful in the above molding processes to form composites would be desira~le. The present invention includes the composites made from the low-viscosity solutions as described in the above citad United States Patent No.
4,433,11~.
The composites of the invention comprise from about 20 to 70 weight percent preferably 45 to 70 weight percent based on the weight of the composite, of a reinforcing material and from 30 to 80 percent, preferably 30 to 55 weight percent based on the weight of the composite, of the reaction product of a liquid thermosetting solution which comprises; 40 to 80 weight p0rcent, preferably 50 to 70 weight percent, based on the liquid solution, of '70~'7 - lOA -one or more of the hemiform~ls as described herein and from 20 to 60 weight percent, preferably 30 to 50 wei~ht percent, based on the liquid solution, of one or more of the polymers as described below.
The liquid thermosetting solutions useful for use in the composites of the invention comprise a hemiformal and a polymer.
The hemiformal compositions useful in the composites of the invention can be represented by the following formulas:

D-128~4-1 1~7097 (IV) O~CH2O)~H
~3 ~x (V) OH

RX ~}(C~120(OE120bH)C
~CH20H)d (VI) ~ C~2)nH
Rx~ ~ CH20 ( CH2bH ) c (~H2OH~d wherein n is a positive number of at least 1, preferably about 1 to about 5, most preferably about 1.2 to about 2.5. b iB 1 to about 5, c iB 1 to about 3, and d is O to about 2, x is O to 3, the sum of c and d is at least 1 ~nd no greater than 3 and the sum of c, d, and x is at lea~t 1 but no greater than 5, where x=O for ~t least 50 mole percent of the hemiformal, and with respect to the R
substituent, ~t least 2 of the or~ho- and para-positions are free in relation to the -OH and -O~CH2)nH groups. It is underseood that these numbers for n, b, c, d and x represent average values and an actual hemiformal composition will comprise a equilibrium mixture of various hemiformals of phenol as represented by the above formulas. R is ~ny substituent typically employed in conjunction with ~ phenolic ~tructure. With respect to R~ it is preferably a monovalent radical which includes alkyl of fxom about 1 to about 18 carbon atoms, cycloal~yl from 5 to 8 carbon ato~s, ~2~7097 aryl containing ~rom 1 to about 3 aro~atic rings, aralkyl, alkaryl, slkoxy containing fro~ 1 to about 18 carbon atoms, aroxy cont~ining 1 to 3 aromatic nuclei, h~lide such as choride, bromide, fluoride, and iodide: alkyl ~ulphides having from 1 to ~bout 18 carbon atoms, aryl sulphides having from 1 to about 3 aromatic nuclei, and the like with the proviso that at least 50 mole percent of a hem~formal mixture be unsubstituted with respect to R, i.e. x ~ 0 for 50 mole percent of the ~emiformal composit$on.
The hemiformals shown above are formed by the reaction o formaldehyde with the hydroxyl-group of a pnenol t~ ror~ ~le~iror~16 of ~n~2..01~ and/or the reaction with the methylol group of a methylolated phenol to form hemiformals of methylolated phenol.
Thi.s i5 accompl~shed by reactin~ formaldheyde with liquid phenol and/or with a solution containing methylolated phenol.
The liquid phenols suitable for use in forming hemiformals of phenol useful in the invention are of the formula:

OH
~x where R and x are def ined above and where at least 50 mole percent o~ the phenol is unsubstituted wiSh respect to R. The substitution with respect to the R substituent should be such that at least two reactive sites on the aromatic ring of the para- and ., ~ . .

- 13 ~ 1 ~ ~ 0 9'7 ortho positions in relation ~o the phenolic hydroxy remain free. ~he liquid phenol may be in ~olution wi~h a 601vent, that i8 unreactive to phenols and aldehydes, or be essentially pure molten phenol.
S Preferably, the phenol i8 molten phenol. Another source o~ suitable liquid phenols are those prepared by reacting phenol and an oil such as linseed oil or tung oil in the presence of an acid ion exchange resin. It is well known that these so-called oil-modified phenols comprise complex mixtures containing phenol and vari OU6 subs t i tut ed phenols derived from reaction of the phenol with the sites of unsaturation in the carbon-chains of the oils.
The resulting substituted or modified phenol mixture can then be treated with formaldehyde as is described herein to produce a hemiformal mixture.
In using oil modified phenols to maXe hemiformals, at least 50 mole percent of the phenol should be unreacted with the oils.
The suitable methylolated phenols are of the formula: OH
VIII ~ ~ (CH2H)a where a is 1 to about 3, and R and x are defined above, and the sum of x and a does not exceed 5.
Although the methylolated phenols can be isolated and reacted as such with formaldehyde to form hemiformals, they are preferably formed in situ by reacting a liquid phenol, as defined above, and formaldehyde in the presence of a divalent metal catalyst defined below. Thus, hemiformals of methylolated phenol can be formed directly from liquid phenols without isolating the methylolated - . . .. .... .. .. . . . .

~ 14 -~2~7~

phenol~ ~enerally, when phenol and formaldehyde are reacted without ~ divalent metal ~atalyst essentially no methyl~lated phenol is formed, the ~ncatalyzed reaction forming methylol phonols being S very slow. Therefore, essentially all of the hemiformals ~ormed in a ca~alyst-free reaction mixture are formed by reaction of the phenolic hydroxy ~roup and are represented by formula (IV).
If a divalent metal catalyst is present in a reaction mixture o2 phenol and formaldehyde, methylolated phenols are formed. Therefore, both the phenol hydroxy and phenol methylol groups participate in hemiformal production and equilibrium mixtures of hemiformals of Formulas IV, V and VI are formed. Thus the reaction may be carried out catalyst-free to ~orm hemiformals essentially of Formula IV, or be carried out with a divalent metal catalyst to form hemiformals of Formulas IV, V and VI.
The catalyst-free reaction to form hemiformals of Formula IV is preferably carried out by passing gaseous formaldehyde through molten phenol. The molten phenol may be phenol ~r se or phenol which is oil-modified or substituted with R
as characterized above. The gaseous formaldehyde may be obtained from a number of sources. A
preferred method of producing gaseous formaldehyde is by heating and decomposing paraformaldehyde into formaldehyde and passing the formaldehyde, free of water, into molten phenol. Another method for producing gaseous formaldehyde is to take the formaldehyde directly as produced by the oxidative decomposition of methanol and introducing the formaldehyde, free of water, to the molten phenol.

The reaction between the ~onomeric or ga~eous formaldehyde and the molten phenol take6 place at a temperature ~t which the phenol i6 molten, such as from melting point of un~ubstituted phenol, about 40C to about 75-C, preferably about 45C to about 60-C.
When using substituted phenols the ~elting temperature may differ, therefore the reaction temperature may need to be higher to achieve a molten phenol. In any case the temperature ~hould not exceed 75C, As stated above it is desirable that the gaseous formaldehyde should be free of water.
However, providing formaldehyde which is free of water is quite difficult to do and in the normal case water will be introduced with the formaldehyde which is provided to the reaction. Usually the amount of water which is tolerable in the practice of this invention is that a~ount of water which will provide in association with the hemiformal a water concentration of up to about 15 weight percent, basis the total weight of the hemiformal composition. In the preferred embodiment it is desirable that the a~ount of water which is present in the resultant he~iformal not exceed about 5 weight percent, basis the total weight of the composition.
As described above, the reaction to form essentially only he~ifosmals of Formula IV does not have to be carried out in the presence of ~ny catalyst and preferably the reaction is carried out in the absence 9 any catalyst. The typical acidic or basic catalysts which are utilized in the reaction of phenol with formaldehyde to produce resinous structures adversely affect the formation of the hemiformal and their absence from the reaction is highly preferred.
The reaction between the gaseoue formaldehyde and the molten phenol is carried out with stirring so as to effect intimate admixture of the reactants and to a~sure uniform reaction. The reaction may be carried out at subatmospheric or superatmospheric pressures, however, in the usual case one will practice the hemiformal reaction at atmospheric pressure conditions. Since the uncatalyzed reaction between forma~dehyde and phenol to make the phenol hemiformal is only mildly exothermic, very little in ' the way of temperature control is necessary in order to produce the desired hemiformal products.
The reaction carried out in the presence of a divalent-metal catalsyt to form an equilibrium mixture of hemiformal6 of formulas IV, V and VI is preferably carried out by reacting essen~ially water-free paraformaldehyde with molten phenol at a temperature of about 60-C to 100C preferably about 80~C to about 90C.
The reaction takes place in the presence of a divalent metal cation such as magnesiu~, calcium, lead, manganese, strontium, barium, zinc, cadmium or mercury, at a pH of about 3 to 8, preferably from about 4 to 6. Typically, the metal cation is supplied as a salt or as an alkoxide such as a carboxylate salt, or a methoxide or ethoxide of the metal in combination with a mild acid to achieve the desired pH. Suita~le sal~s include the formates, acetates, benzoates, and valerates. Examples of these salts include zinc acetate dihydrate, calcium formate, manganous acetate, lead acetate and zinc D-12824-l - 17 ~ ~ ~709 benzoate.
The divalent ~etal catalyst is typically present at a concentration of about 0.2 to 1 weight percent, preferably about 0.4 to about 0.7 weight percent, based on the total weight.
The paraformaldehyde can be introduced directly to the liquid phenol. Preferably the paraformaldehyde is water-free.
As ~tated above it is desirable that t~e 0 paraformaldehyde be es~entially free of wa~er.
However, providing a ~ource of paraformaldehyde which is free of water is quite difficult to do and in the normal case water will be carried along with the paraformal-dehyde which is provided to the reaction. Usually the amount of water which is tolerable in the practice of this invention is that amount of water which will provide in association with the hemiformal, a water concentration o~ up to about 15 weight percent, ba~ed on the total weight of the hemiformal composition. In the preferred embodiment it is desir~ble that the amount of water which is present in the resultan~ hemiformal not exceed about 5 percent, based on the total weight of the hemiformal composition.
The reaction between parafor~aldehyde and the molten phenol is carried out with stirring so as to effect intimate admixture of the reactants and the metal catalyst and to assure uniform reaction.
~he reaction may be carried out at subatmospheric or superatmospheric pressures, however, in the usual case one will practice the hemiformal reaction at atmospheric pressure conditions. Since the catalyzed reactions between formaldehyde and phenol to ~ake phenol hemiformals, methylolated phenols and ~-12824-1 7~

hemifor~als of methylolated phenol, are exothermic, a cooling ~ater bath may be required to maintain the reaction temperature.

The polymer~ suitable for use in the liquid thermosetting solutions used in the invention are of the phenol-for~aldehyde resole, phenol-formaldehyde novolac, aromatic polyester, polycarbonate, unsatureated polyester, poly(aryl-ether), urea-~ormaldehyde and ~elamine-formaldehyde type. They must be mi~ci~le with the hemifor~al and be capable of forming a ~olution with the hemiformal that has a viscosity low enough to be useful in injection molding or sheet ~olding compound methods. The viscosity of the hemifor~al-polymer solution is preferably less than about 500,000 cps for use in sheet molding compound methods and most preferably le~s than about 10,000 Cp5 for use in molding methods such as LIM, RIM or RTM. The viscosity depends on the concentration and molecular weight of the polymer or polymers u~ed.
The phenol-formaldehyde resole polymer6 that can be used in the composites of the invention include phenolic resins produced by reacting ~n aldehyde and phenol at an aldehyde to phenol molar ratio equal to or greater than one, generally ~reater than one, and generally in the presence of an alkaline cat~lyst. Resoles are generally characterized as eo~positions that can be cured to a ther~oset state by the application of heat without additional aldehyde. The aldehyde component is usually formaldehyde, although not restricted to it. Other aldehydes ~uch ~s acetaldehyde, furfuraldehyde and the like can replace part or all ~L2~ 97 of the formaldehyde employed in the preparation.
Those skilled in the ~rt are fully familiar with resoles, their ~tructure, and methods of manufacture.
The phenol-formaldehyde novolac polymers that can be used in the composites of the invention are phenolic resins that require additional aldehyde or its equivalent, such as hexamethylene~etramine, to cure to a thermoset s~ate. They are produced by reacting an aldehyde and a phenol at an aldehyde to phenol ratio of less than one, usually in conjunction with an acidic catalyst. Those skilled in the art are fully fa~iliar with novolacs, their structure, and methods of manufacture.
The aromatic polyesters useful in tne composites of the invention can be obtained by the condensation of a difunctional phenol or mixture of difunctional alcohol and phenol with a dicarboxylic acid. The polymerization is performed in 6uch a way that the resulting polyester contains the phenolic moiety as the terminal group. An~ong the difunctional phenols useful for the preparation of these polyesters one can name hydsoquinone, 2,2-bis-(4-hydroxyphenyl~propane (bis-phenol A), bis(hydroxyphenyl)ether, bis(hydroxyphenyl)-thio-ether, ~is(hydroxyphenyl)-methane, bis(hydroxy-phenyl)sulfone, and the like. Suitable difunctional alcohols include ethylene giyco_, butanediol, hexanediol, cyclohexane dimethanol. Among the suitable dicarboxylic acids are maleic acid, fumaric acid, terephthalic acid, isophthalic acid, naphthalene dicarboxylic acids as well as alXyl substituted homologs of these acids, whesein the alkyl groups contain fsom 1 to 4 carbon atoms.
Otner suitable dicarboxylic acids are ylutaric acid, .

~2¢7097 adipic ~cid, suberic ~cid, azelaic acid, seb~clc acid, and dodecane dioc acid.
The arom~tic polyesters useful in the compositions of the invention may cont~in any substituent which will not adversely Qffect the miscibility or solubllity of these polymers in the hemiformal or the subsequent cure of the mixture to a thermosee~ Among such substituents one csn name halide, hydrocarbyl, alkoxy, ether and thioether.
Illustr~tive of suitable aromatic polyesters for use in the compositions of this invention one can n~me bisphenol-A terminated, poly(bisphenol-A iso- or terephthalate), bisphenol-A
terminated polyethylene terephthslate, snd the like. A preferred arom~tic polyester is the poly(bisphenol-A iso- or terephthalate) of the general formulQ
1~0~ O-CO--3--CO ~ 0_~

Preferably, the aromatic polyesters should have a molecular weight less than ~bout lO,000.
The unsatur~ted polyesters useful in the compositlons of this invention are well known; these polyesters are ch~racterized by having at least one internal or terminal unsaturat~on, i.e., -C=C-, which is capable of reacting with a phenol or methylol phenol compound by an alkylation reaction of the double bond and an ortho- or para- position to the hydroxyl of the benzene ring. Gener~lly, due to availability or ease of preparation the uns~turated polyester is structopendant, i.e., the re~ctive unsaturation 1s present at ~n internal rather than at a terminal position ~nd usually the internsl D-12824-l i~

~ 7()9~
unsaturation i~ alpha to a carbonyl group.
The ~uitable struct~pendant unsaturated polyesters are rea~tion products of maleic anhydride, maleic acid and/or fumaric acid with a difunctional alcohol such as propylene glycol, diethylene glycol, lt3-butanediol and the like or a dihydroxy phenol such as ~ phenol A, and the like, or hydroquinone and the like. Isophthalic ~cid and/or terephthalic acid m~y also be included in the mixture. A preferred unsaturated polyester is a poly~er formed by reaction mixture of isophthalic and/or terephthalic acid, maleic acid and/or fu~aric acid and a difuncional alcohol of the formula HO-R'-OH where R' is a substituted or unsubstituted alkylene or arylene, ~aid polymer having the repeating unit;
n - C-CH=CH-CO-O-R'-O-CO ~ CO-O-R'~O-The unsaturated polyesters useful in the compositions of this invention may contain any substituent which will not adversely affect the miscibility of these polymers in the he~i~ormal or the subsequent cure of the mix~ure to a thermoset.
Am~ng such substituents one can name halide, hydrocarbyl, alkoxy ether ~nd thioether. Preferably the molecular weight i~ less than lO,OOO.
The aromaeic polycarbonates useful in the invention are polyesters of carbonic acid and a dihydric phenol.
The polycarbonates are pepared by reacting the dihydric phenol with a carbonate precur~or.

D-12824-l ~LZ~7~97 Typical of some of the dihydric phenols th~t may be employed Are bisphenol-l, bis(4-hydroxyphenyl)-methane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 4,4-bis(4-hydroxyphenyl)-heptane, (3,3'-dichloro-4,4'-dihydroxydiphenyl)meth~ne, and the like. The terminal group of the dihydric phenol should be phenol which has at least one para- or ortho-position to the phenolic hydroxy ~ree for reaction with the hemiformsl. Other dihydric phenols of the bisphenol type Are described in, for example, U.S.
Patents 2,999,835, 3,02B,365 ~nd 3,334,154.
It is, of course, possible to employ two or more different dihydric phenols, or a copolymer of a dihydric phenol with a glycol or with hydroxy or acid termin~ted polyesters or with u dlbasic ecid in the event a carbonate copolymer or inter-polymer rather than ~ homopolymer ls derived for use in the preparstion of the aromatic carbonate polymer.
The carbon~te precursor may be either a carbonyl h~lide, a carbonate ester, or a haloform~te. The carbonyl halides which c~n be employed herein are carbonyl bromides, carbonyl chlorlde ~nd mixtures thereof. Typ1cal of the c~rbonate esters which may be employed herein are diphenyl carbonate, di(halophenyl)carbonates such as dl-(chlorophenyl)carbonate or di-~bromophenyl)car-bonate, etc., di-(~lkylphenyl)csrbon~tes such as di(tolyl)cflrbonate, di(naphthyl)carbonate, di(chloronaphthyl)carbonate, etc., or mixtures thereof. The haloformates suitable for use herein include bls-haloformate of dihydric phenols for example, b~schloroformates of bisphenol-A, of hydroqu~none, etc., or glycols, for example, bishaloformates of ethylene glycol, neopentyl 1;2~7097 glycol, polyethylene glycol, etc. ~le other carbonate precursor~ will ~e apparent to those skilled in the ar~, carbonyl chloride, al50 ~nown as phosgene, is preferred.
The aromatic polycarbonate polymers may be prepared by methods well Xnown in the art by using phosgene or a halofor~ate and by employing a molecular weight regulator, an acid acceptor and a catalys~. The ~olecular weight regulators which can be employed in carrying out the process include monohydric phenols, such as phenol, para-tertiary-butylphenol, para-bromophenol, primary and secondary amines, etc. Preferably, a phenol is employed as the molecuar weight regulator.
A suitable acid acceptor may be either an organic or an inorganic acid acceptor. A suitable organic acid acceptor is a tertiary amine and includes materials, ~uch as pyridine, tsiethylamine, dimethylaniline, tributylamine, etc. The inorganic acid acceptor may be one which can be either a hydroxide, a carbonate, a bicarbonate, or a phosphate of an alkali or alkaline earth metal.
The catalysts for making an aromatic polycarbonate can be any of the suitable catalyst~
that aid the polymerization of, for example, bisphenol-~ with phosgene. Suitable catalysts include tertiary amines, such as triethylamine, tripropylamine, N,N-dimethyl-aniline, quaternary ammonium compounds, 6uch as tetraethylammonium bromide, cetyl triethyl ammonium bromide, tetra-n-heptylammonium iodide, and quaternary phosphonium compounds, such as n-butyltriphenyl-phosphonium bromide and methyl triphenyl phosphonium bromid2.

~ 24 -~Z~7097 The aromatic polycarbonates can be prepared in a one-phase (homogeneous solution) or two-phase ~interfacial) sy6tems when phosgene or ~ halofor~ate are used. Bulk reactions are possible when the diarylcarbonate precursors are used.
The aromatic polycarbonates useful in the compositions of this invention may contain any substituent which will not adversely affect the miscibility of these polymers in the hemiformal or the subsequent cure of the mixture to a thermoset.
Among such substituents one can name halide hydrocarbyl, alkoxy, ether, and thioether. The aromatic polycarbonates 6uitable for use in the invention preferably have a molecular weight less than about lO,OOO.
The poly(aryl-ether) resin components suitable for use in the invention are linear, thermoplastic polyarylene polyether polysulfones, characterized by arylene units interspersed with ether and ~ulfone linkages, and by at least one terminal or pendant phenol moiety which is capable of reacting with an aldehyde or methylol phenol compound. These resins may be obtained by reaction of an alkali me~al double salt of a dihydric phenol and a dihalobenzenoid compound, either or both of which contain a sulfone or ketone lir.kage i.e., -SO2- or -CO- between arylene groupings, to provide sulfone or ketone units in the polymer chain in addition to arylene units and ether uni.s. The polysulfone polymer has a basic structure comprising recurring units of the ~ormula.
O E O E' wherein E is the residuum of the dihydric phenol and E' is the residuum of the benzenoid compound having D-12824-l , ~, .. ..
' - .~ ' :' - 2~ -~l2~7~)97 an inert electron withdrawing group in nt least one of the positions ortho and para to the valence bonds; both of said residua are valently bonded to the ether oxygens through aromatic carbon atoms.
Such polysulfones are included within the class of polyarylene polyether resins described in U.S.
patent 3,264,536 and 4,1~8,837, for example~ A
terminal phenol can be obtained by using a stoichiometric excess of the dihydric phenol component so that the terminating group is derived from the dihydric phenol component.
The residuu~ of a dihydric phenol, E is derived fro~ dinuclear phenols haYing the structure:
~A)r (Al ) r OH(Ar Rl Ar)OH
Wherein Ar is an aromatic group and preferably i5 a phenylene group, A and Al may be the same or different inert substituent groups, such as alkyl groups having from 1 to 4 carbon atoms, halogen atoms, i.e., fluorine, chlorine, bromine or iodine, or alkoxy radicals having from 1 to 4 carbon ato~s, r and rl are integers having a value of from O to 4, inclusive, and Rl is representative of a bond between aromatic carbon atoms as in dihydroxydi-phenyl, or is a divalent radical, including, forexample, Co, O, S, S-S, SO2 or a divalent organic hydrGcarbon radical, ~uch as alkylene, alkylidene, cycloalkylene, or the halogen, alkyl, aryl or like substituted alkylene, alkylidene and cycloalkylene radicals as well as alkarylene and aromatic radicals and a ring fused to both Ar groups.
Typical preferred poly(aryl-ether) poly~ers , . ;

- 26 - ~ 2~7 0 g 7 have recurring units having the following ~tructure:
tA)r (~l)r R2 e;3 as described in U.S. Patent 4,108,837, supra. In the foregoing formula A and Al can be the same or different inert substi~uent groups that will not adversely affect the fiolubility or miscibility of the polyme~ in the hemiformal or the subsequent cure to a thermoset. These include alkyl groups having from 1 to 4 carbon atoms, halogen atoms (e.g.,.
fluorine, chlorine, bromine or iodine) or alkoxy radicals having from 1 to 4 carbon atoms, r and r are integers having a value of fro~ 0 to 4, inclusive. Typically, Rl is representative of a bond between aromatic carbon atoms or a divalent connecting radical and R2 represents sulfone, carbonyl, or sulfoxide. Preferably, Rl represent~
a bond between aromatic carbon atoms. Even more preferred are the thermoplastic polysulfones o~ the above formula wherein r and rl are zero, Rl is a divalent connection radical of the formula:
I
R" C - R"

wherein R" is selected from lower alkyl, aryl, and the haloge~ substituted groups thereof, preferably methyl and R2 i5 a sulfone group.
The most preferred poly(aryl-ether) polymers are polysulfones are those having the general formula:

H0 ~ ~ 0 ~ - S2 ~ - ~ ~ ~ n ~2~709~7 Where n is ~uch that the molecular weight of the poly(aryl ethers) used in the invention i8 preferably less than lO,OOO, most preferably less ~han 5,000.
The urea-formaldehyde resins useful in the ccmpositions of this invention are produced from the reaction of for~aldehyde with the -NH2 groups of the urea. The initial base catalyzed reaction between formaldehyde and urea produces methylol-, dimethylol- and ~ri~ethylolureas. This reaction is followed by condensation reactions that eliminate water to form polymers. This mixture of low molecular weight polymers and methyiolureas is known as urea-formaldehy~e resin ~hich on ~.eati~g yields insoluble, infusible, crosslinked products. The preparative reactions are illustrated by the idealized s~ructures depicted in the equation below:
2 2 2 > HO-CH2NH-CO-NH2 +
HO-~H2NH-CONH-CH2t)H
HOCH ~
~ N-CO-NHCH2OH

NH ( CH2 - N~ ) CO CO
HOCH2-~H NH

where R is CH2OH or H.
Preferab~y the urea-fcr~alde~yde resin are free of volatile sol~ents such as water, alcohol~, and the like.

~-12824-1 - 2B - ~ Q97 The ~ela~ine-formaldehyde resins u~eful in th~ ~ompo~itio~6 ~f this inventi~n are produced from the conden~tion of for~aldehyde with the ~mino group~ ~f ~el~mine (2,4,6 -tri~ino-1,3,5- triazine) S gener~lly ~n~er ~a~ic pH conditions. One ~le of the ~elamine can r~act with 1-6 ~ole~ ~f formal~ehyde yielding ~ono, di-, tri, t~tra-, pent~-, and hexa~ethylcl~elamines. These ~ethylol ~erivatives further poly~eri2e with the eli~ina~isn w~ter for~ing ~el~ines linked by ~ethylene and ~ethyl~ne either bridges. The r~aetion i~
illustrated by the following equ~tion:

f ~ 2 HOCH3~ NHCH2OH
~/' ~1/
~H2 NH2 ~CH2NH ~ ~ HCH2NH ~ _ NHCH2OH
~aH2 hH;~CH20H

HOCH2NH ~ ~I~ NHcH2ocH2NH ~ NHCH20H

~urther condensation of the ~elamine-~or~ldehyde recin, ~celer~ted by he~t or ~cid ,~,~
, ~

'70g7 catalyst, nnd especially when tri- to hexamethylol~elamine derivatives are involved yields crosslinked structure~.
Preferably the ~ela~ine-~ormaldehyde resins are free of volatile solvents such as water, alcohols and the like.
The thermosetti~g composition~ useful in this invention ~re prepared by admixing the phenol-formaldehyde resole, phenol-~ormaldehyde 0 novolac, aromatic polyester, unsaturated polyester, aromatic polycarbonate, poly(aryl ether), urea-formaldehyde or melamine-~ormaldehyde polymer with the phenol hemiformal and/or ~ethylolated phenol hemiformal in the previously described concentrations and in a manner such that a solution is obtained with a viscosity less than about 50~,00 centipoise and preferably less than about 10,000 centipoise, depending on the molding method to be used. The admixture ~ay be carried out at any suitable pressure, at~ospheric pre~sure bein~
convenient, and at a temperature of ~rom about a~bient temperature (about 20~C) to about lOO-C, preferably from about 60-C to about 80~C. It is generally advantageous to agitate the ~ixture vigorously during the preparation to facilitate dissolution. The resultin~ mixtures comprise liquid thermosetting compositions which are curable to thermosets.
The liquid co~positions can be cured by the .
addition of heat. Generally, a catalyst is also added to the composition to enhance the cure rate.
Either acids, such as sulfuric and toluene sulfonic acid, or bases, ~uch as organic amines, &lkali or alkaline earth hydroxides, can be employed ~l2U7~9~7 a6 the aforeme~tioned catalyst. In general, substances which can catalyze phenol/aldehyde condensation reactions can be employed as the catalyst for the ~uring reaction. The selection of tha type and concentration of the catlyst depends on the molding process and the cure rate desired. For exanple, when employed in a process such as that for sheet molding compounds, wherein the cure of ~he molding composition i5 interrupted at some inter~ediate ~ttage for ~torage or additional handling, less ~ctive ca~alysts and less vigorous curing conditions would be required. For liquid injection ~olding or reaction injection molding ~perations where short cycle time is desired, a more active catalyst and at a hi~her concentration is of greater utility.
A~ong the ~cidic catalysts which have been successfully employed are included phenol sulfonic acid, phosphoric acid, maleic acid, chlorosulfonic acid, toluene sulfonic acid and many others. Phenol sulfonic acid has been found to be quite convenient and is readily obtained by dissolving sulfuric acid in phenol. For processes such as liquid injection molding or reaction injection molding the preferred catalyst is an acidic catalyst at a concentration of about 0.2 to 5 weight percent based on the weight of the uncatalyzed liquid composition. For processes such as sheet molding compounds, the catalyst is preferably a less active catalyst such as basic catalysts like amines at a concentration of up to 10 weight percent based on the weight of the uncatalyzed liquid composition.
The actual concsntration will depend on the activity of the catalyst used. These catalysts and their activi-ties in phenol/aldehyde condensation reactions are well known in the art.

--- . . .... . . ~ .. . ..

~2~7~97 The preferred curing procedure wherein the catalyst is preferably introduced to the liquid compositions of ~hi6 invention before the curing step may be termed a one-component ~ystem. In such a sy~tem the catalyst level is adjusted such that c~re is substantially avoided during handling prior to injection into a mold. The mold is at a higher temperature, generally greater than 80C, 50 that the curing reaction i8 activated thermally. Once activated the curing reaction accelerates due to heat evolved by the exothermic reaction.
Another procedure, which may be termed a two-component i~ystem, may be employed when one does not wish to keep the composition containing the catalyst in such a ~tate for very long before injection into the mold. In such a two-component sy6tem an acidic catalyst is introduced into a solution of phenol and the polymer. This mixture i5 then pumped and metered into a mixing device concurrently with and separately from the hemiformal such that the components are mixed in the mixing device. After mixing, the liquid composition of this invention which contains a catalyst is injected immediately into a mold where the cure takes place.
The liquid composi'ion of this invention which has had catalyst added thereto, which may be termed a liquid prepolymer, and which may be prepared by either the one or two-component ~ystem described above, or any other convenient method, should have a total aldehyde to total phenol molar ratio of from 1:1 to 2:1, preferably from 1.1:1 to 1.8:1, most preferably from 1.2:1 to 1.5:1.
By total aldehyde and total phenol, it is meant the total amount of ~uch moieties existing as ~Z~709~
free aldehyde or phenol or the equivalent thereof present in the hemifor~als or the polymere in the solution. The ratio m~y be adjusted by addition of ~ phenol, an aldehyde or additional hemiformal to the prepolymer.
The li~uid prepolymer composition~ are cured by the application of heat. A temperature of from 80CC to 200-C, preferably from 120C to 160C, is employed ~or the cure. The curing ti~e will vary and will depend on such factors as the particular makeup of the ~hermosetting composition, the temperature, the a~ount to be cured, the configuration of the cured part, and other factors known to those in the art. Generally curin~ times are from 1 to 15 minutes.
Suitable reinforcing materials useful in the composites of the invention include glass fibers, carbon fibers, graphite fibers, wollastonite, cellulousic fibers such as wood flour and the like, organic fiber~ ush as aromatic polyamide ibers, and mica.
The preferred reinforcing materials are glass fibers, graphite fibers and aromatic polyamide fibers. These fibers may be in any form common to the art such AS chopped fiber, mat, and woven cloth. In injection processes the fibers may be introduced into the thermosetting composition by mixing therewith before injection into the mold; or preferably, the fiber is placed into the mold and the thermosetting composition is injected therea~ter. In sheet moldin~ compounds the fiber may be mixed as chopped fiber prior to the initial cure.
Other additives may be included in the ~Z~7097 composites of the invention. These include those com~only u~ed in the above molding method~, ~uch as pigments and various processing aids.
The composites of the invention show superior physical properties and have content of reinforcing material unobt~inable in the prior art.
Because of the reactivity and low viscoity of the liquid thermosetting ~olution used, the composites are easily ~ade rom conventional molding processes.
T~e following examples serve to further illustrate the invention. They are not intended to limit the invention in any way.
In the examples the following evaluation procedures were employed.
Flexural Modules - ASTM D790 Flexural Strength - ASTM D790 Notched Izod - ASTM D256 Heat Distortion Temperature (HDT) (264 psi) AS~M D648 Tensile Modulus - ASTM D638 Tensile Strength - ASTM D637 Elongation - ASTM D638 Vertical Flame - UL-94 Example 1 Methylolated phenol hemiformal was prepared as follows: to a 5 liter reaction flask equipped with a thermometer, ~tirrer and addition-port there were charged 1410 srams ( 15 g-moles ) of phenol, 74~
grams of 91 mole percent paraformaldehyde (parafor~) (22.5 g-moles formaldehyde equivalent) and 10.8 grams of zinc ~cetate dihydrate as catalyst. The mixture was stirred and heated to 85~C for about 20 minutes. A ~ild exotherm ensued. The re~ction 709~

mixture was m~intained at from 80 to 90C by removsl of the external heat source ~nd by occ~sional cooling with a water bath. After the exotherm subsided, heat was reapplied to maintain a reaction mixture temperature of from 80 to 9~C until a cle~r solution was obtained; this took from Qbout 1 to 2 hours. Nuclear magnetic reson~nce showed the product to be ~ mlxture of hemiform~ls of phenol ~nd hemiformals of methylolsted phenol.
Eight liquid resin compositions were prepared by dissolving various phenol-formaldehyde resole and novolac resins in a hemiformal of methylolated phenol. For runs 1 to 5 the hemiformal prep~red above WRS used. For runs 6 to 8 a hemiformsl was used that was prepared in the ssme manner ~s above except that 659 grsms of 91 weight percent paraform~ldehyde (equivalent to 20 moles of formaldehyde), 940 grams phenol (10 moles) ~nd 4.7 grams of zlnc acet~te dihydr~te were uæed. The resoles h~d an Inclined Pl~te Flow of 40-90 mm at 125C. The novolacs h~d an Incllned Plate Flow of 60-80 mm when copulverized with 9~
hex~methylene-tetremine, b~sed on the total weight of the mixture. The Inclined Plate Flow W2S
determined by compressing ~ one-grsm semple of a pulverized product to ~ pellet 12-13 mm in diameter. This pellet w~s pl2ced on 8 glQSS plate ~nd heated for three minutes in ~ 125C oven. The plste w~s then tllted to ~ 60 ~ngle ~nd hesting continued for an additionel 20 minutes. The distance, measured in mm, the resin travelled is known ~s the Inclined Pl~e Flow. The Inclined Plate Flow reflects both the melt viscosity and cure r~te of the resin.

~-r / :3"

'~ TAEIT-F I
., Formaldehyde/Phenol V1scosity Mole Ratio Poly~er Liquid Recin Compo~itlon ~rookfield RunIn Hemiformal Type Hemiformal ~wt ~ Polymer ~wt ~) cp~, C
1 1.5 Resole, lumps 70 30 1,500, 40C
2 1.5 Resole, lumps 60 40 5,000, 40~C
.-; , 3 1.~ Resole, lump~ 50 50 20~000, ~0C
'" ! . ' S 1.5 Resole, powder 70 30 1,15G, 50-C
., 5 l.S Resole, powder 60 40 6 2.0 No~olnc, flake~ 70 30 540, 50-C
~' 7 2.0 Novolac, flakes 60 40 1,300, 50-C
8 2.0 Novolac, flakes 50 50 6,800, 50C ~n s ''''~' ' ' C:~
.~'.

~!
., .
-''-;'' ,, :;' ,~, ~LZ~7097 The hemiformal was heated t~ about 50C to 70C ~nd agit~ted ~s the polymer was ~dded. In T~ble I are shown the formaldehyde to phenol ratio of the hemi$ormal used, the polymer type ~nd its S form, the compRrative perc~nt~ges of the hemiform~l snd polymer in the liquid thermosetting composition, ~nd the Brookfield viscosity of the liquid thermo-setting composition for e~ch run.
ExamPle 2 Liquid resins prepared in Example 1 were cured ~nd used to form reinforced composites by the following procedure. A reactive liquid prepolymer was prepRred by Rddin8 ~ solution of phenol and sulfuric acld to a liquid resin of Ex~mple 1 to form ~ liquid prepolymer containing phenol sulfonic acid. The added phenol to sulfuric ~cid welght ratio was 9. The welght percent, of the added phenol-sulfuric acld cst~lyst, based on the total liquid prepolymer, is shown in Table II, as ~re the p~rticul~r liquid resins from Ex~mple I th~t were used. The c~tslyzed mixture w~s then chRrged into mold cont~ining 5 fiber-glass m~t. The fiber-gl~ss m~t was type AKM avail~ble from PPG Industries, Inc., Pittsburgh, Pennsylv~nia. The mold was pl~ced in ~ press and hested to curing temperature. The temperature r~nges of the cure and the curing times ere shown in Table II. The content of fibergl~ss in weight and volume percent ~nd the content of thermosets composition in the cured composites Are also shown. In Runs 9 to 11 equ~l amounts by weight of the resins prep~red in Runs 4 and 6 of Example l were used.
E~ch composite was evalu~ted ~nd the results ~re reported in T~ble III. As the results TA~L.E II

i Liquid Resin Co~po~te ~itior~ fro~Ca~lyst Mold Temp.Cure Ti~e Fibe~glass Fibergla~ ~hermo~et ~o. Run (Wt ~) ~C~ (min, ) ~Vol. ~ ~wt. 11) ~wt.
4 0.04120-150 15 46 65 35 2 4 0.0~14û-160 14 47 66 34

3 4 0.04150 1~ 33 52 48 , 4 5 0 . 03 147-150 10 24 40 60 5, ~ 0.04150 11 ~ 36.5 63.5 ;- 6 1 0.1120-150 8 q5 63.6 36.
0.1 120-15010 - 31 49 51 6 1 0 . 1 120-150~ 20 35 65 9 9 ,6 O .0412G-155 13 49 67 33 - 10 4,6 ~.04110-150 14 43 62 38 11 ~,6 û.04140-153 1~ 21 37 63 .. 12 4,6 0.0~120-150 12 21 ~Ç.4 63.6 13 4,6 0.04liO-150 16 35 53.6 46.4 s i TABLE III

~lexural Flexural Tengile Tensile Elongation HDT Notched Izod Compo~te Mbdulu8 Strength Mbdulus Strength ~ C (ft-lb/in Notch) No. (lo-6 p~i) (10 4 psi (10-4 i 10-4 i (264 p~i) 1 2.02 3.45 1.91 2.55 1.55 260 25 - 2 1.94 3.3 1.73 2.58 1.8~ 260 27 ' 3 1.5 3.5~ 1.5 2.09 1.6 260 21

4 1.27 2.85 1 1.~3 1.83 260 15

5 ' l.li 2.7 1.02 1.28 1.55 26~ 15

6 1.19 2.8 1.72 2.53 1.7 260 26 ~ 7 1.4q 3.37 1.23 1.71 1.6 260 la ; a 1.08 2.13 1.05 1.29 1.3 260 13 9 ~.14 3.~7 1.~9 2.71- 1.65 2S0 25 1.75 3.46 1.76 2.58 1.65 260 23 - 11 1.19 2.71 1.05 1.36 1.57 260 16 w 12 1.05 2.7 1.12 1.54 1.78 260 15 - . 13 1.27 3.27 1.45 2.29 l.g3 260 20 :
,~ ;

., _' ... .
-. . Q
;7~r,.
".' ' ., ~

7 ~ ~

"
' ' .1 ' ' ` ~' ~2~7097 demonstrate, the fiber-glass reinforced composite prepared with the liquid thermosetting compositions of this Example display excellent mechanical properties and ~llow higher than heretofore possible glass content.
Composites 1 to 3, 6, 9, lO and 13 show particularly high ~lass ~ontent (Table I~) ~nd these composites demonstrate better properties than some of those ~ontaining a lower glass content. This demonstrates the high-fiber content composites contemplated ~y the present invention and the excellent mechanical properties thereof, particularly with respect to impact resistance.
Typically, phenol-formaldehyde resins composites of the prior art have a notched izod impact resistance of the order of about 1 ft-lb/in, many having an impact resistance as low as about 0.4 ft-lb1in.
This is at least an ordex of magnitude lower than the notched izod impact resistance of the composites of ~he invention, as i8 demonstrated in Table III
wherein composites having an impact resistance of from 13 to 27 ft-lb/in are shown.
Example 3 Composites were ~ade as the composites numbered 4, 9, and 11 (Table II) made in Examples 2. These were evaluated for fire resistance using the vertical flame test UL-94, wherein the composites are ignited with a flame. Table IV shows the thickness the composite tested and sum~arizes the results ~f the fla~e ~e3t. Shown are the extinguishing times (E.T.) and the drip for a first burn and a second succesive burn. The extin~uishing time (E.T.) is the time it takes for the burning compssite to extinguish itself after the flame is 40 - ~ z~7097 withdrawn. As shown by Table IV the6e times, with one exception, are all 0, which means that these composites ceased to burn as soon as the flame was withdrawn. "Drip" refers to the property of some plastics to form burning liquid drops as th~y burn.
A drip of 0 indicates that no such drops were formed. The data ~hown i~ Table IV demonstrate a superior flame resistance of these composites. Also shown is the rating for each composite as defined by the test used. A V-0 ra~ing is the highest rating for flame resistance for the flame test used.
Example 4 Eleven liquid thermosetting composition~
were prepared by dissolving various polymers in he~iformal compositions.
The hemiformals were prepared as follows.
(a) Preparation of a Phenol Hemiformal. Monomeric formaldehyde was generated by the pyrolysi6 of paraform as follows. A slurry o~
200 gra~s of commercial 95~ paraformaldehyde in 500 ml of mineral oil was charged into a 2 liter flask which was equipped with a stirrer, thermometer, gas inlet and outlet tubes. The mixture was heated at 120C - 140C under a nitrogen atmosphere. The gaseous formaldehyde formed was swept by a stream of nitrogen via heated connecting glass t~bes through a cold trap (-20C) and then fed to 400 grams of molten phenol. Additional paraform in 100 gram portions was added to the mineral oil as it was being depleted by the pyrolysis. The formaldehyde concentration in the hemiformal was deter~ined as ~ollows. About l-1.5 grams of hemiformal was - 41 - lZtI7Q97 ~tirred in ~bout 75 ml of methanol and adjusted to a pH of 4Ø One normal (1 N) ~ydroxylamine hydrochloride solution (75 ml), also at pH 4.0 was added tv the ~ethanol solution and allowed to react for about 1 hour. ~he solution was then titrated wi~h a standarized 0.5N 60dium hydroxide to a pH
4Ø The resulting hemiformal contained the equivalent of 34.4% formaldehyde which corresponds to a phenol/for~aldehyde ratio of 1.6. Five other phenol hemiformals were prepared in the same manner as above, were similarly analyzed and found to have TABLE IV

Composite - First Burn Second Burn No. from Thickness E.T. Drip E.T. Drip 15Table II Imils) (sec) (sec) Rating 11 lOB O O O O

11 11~ 0 0 0 0 4 116 0 0 0 .0 & formaldehyde to phenol ratio of 1.75, 1.87, 1.65, 1.48, and 1.73.
(b) Preparation of a Phenol/p-Cresol Hemiformal - Gaseous formaldehyde was generated by the method dessribed in (a) above and was fed into a 28709~
mixture of 54 grams of p-cresol and 141 grams of phenol at 40 - 60~C. The hemiformal was analyzed for formaldehyde by the ~ethod in ~a) and was found to contain and equivalent of 34.7% formaldehyde corresponding to a ~ormaldehyde to phenol-p-cresol molar ratio of 1.73:1.
(c) Preparation of a Hemiformal of Linseed Oil o Modified Phenol. Linseed Oil-modified phenol was prepared by ~ixing together in a three-necked flask equipped with a stirrer 69.5 grams of Linseed oil, 188 grams of phenol and 2 grams of an ncidic ion exchange resin tAmberlyst A-15) for 4 hours at 150-C. The ion exchange resin was then removed from the linseed oil-modified phenol by fil~ration.
Gaseous formaldehyde was prepared as in (a) above and fed into the modified phenol at 45-6SC.
The resulting hemiformal was analy~ed as in (a) above and found to contain the equivalent Qf 27 percent formaldehyde, corresponding to a formaldehyde'to modified phenol molar ratio of 1.6:1.
(d) Preparation of a Hemiformal of Tung Oil-Modified Phenol. Tung Oil-modified phenol was prepared by mixing together in a three-necked flask equipped with ~ stirrer 52 grams of tung oil;
188 grams of phenol and an acid ion exchange resin (Amberlyst A-15) for 3 hours at 100C.
To prepare the hemiformal, gaseous formaldehyde prepared as in (a) was fed into the modified phenol at 45-65-C. The resulting hemiformal of tung oil-modified phenol was analyzed as in (a) and found to contain the equivalent of 40 percent formaldehyde which corresponds to a for~aldehyde to ~odified phenol molar ratio of . ~ .

~2()7097 2.7:1.
The polymers used in the thermosetting compositions of this example were prepared and characterized as followæ:
(e) Preparation of Unsaturated Polyester. A solution of 2,2-dimethyl-3-hydroxy-propyl 2,2-dimethyl-3-hydroxy-propionate t224.7 grams, 1.1 moles), fumaryl chloride (76.69, 0.5 mole~ and 150 isophthaloyl chloride ~101.5 grams, 0.5 mole) in 1 liter of anhydrous trichlorobenzene was heated at reflux while a stream of nitrogen was sparged through to displace the hydrogen chloride evolved. After about 18 hours, at reflux, the evolution of hydrogen chloride ceased; the un~aturated polyester was recovered by evaporating the solvent under reduced pressure.
(f) Preparation of Aromatic Polyester. A mixture of 31.25 grams (0.3) mole) of neopentyl glycol, 152.3 grams (0.75 g-mole of isophthaloyl chloride and 50.76 grams (0.25 g-mole) terephthaloyl chloride in 3 liters of anhydrous trichlorobenzene was stirred at reflux. The hydrogen chloride liberated was sparged from the reaction mixture with a stream of nitrogen. When hydrogen chloride evolution ceased, which was about 2 3 hours, 171.3 grams ~0.75 mole) of bisphenol-~
was added. Heating and sparging with nitrogen was continued until no more hydrogen chloride was evolved. The solution was cooled and the polyester recovered by coagulation in methanol had a reduced viscosity (in p-chlorophenol at 50C) of 0.2 dl/g.
The aromatic polyester thus formed had the phenol moiety in the terminal position.
(g) The Novolac Phenolic Resin. The ~Z~709~

novol~c resin w~s ~ commercisl resin h~ving an Inclined Plate Flow of 60-80 mm when contQinlng 9 weight percent, bssed on the total weight of the composition, of hex~methy~eneltr~mine.
VRrious solutions of the ~bove described hemiformals wlth the novol~c resin in (g) were prepared by stirring ~he hemiformal at abou~ 60 to 85C while ~dding the pulverized novol~c resin in sm~ll portions over 15 - 30 minutes. The stirring w~s continued until ~ solution resulted; this took an ~dditional 15 - 30 minutes. The composition was then cooled to room temperature.
V~rious solutions of the Above described hemiformals with the aromstic polyesters of (f) and the uns~turated polyester of (e) were prep~red by vigorously stirring 319 grAms of hemiform~l ~t 60 to 70C and sdding an ~mount of polyester over 1 hour to give solutions of the compositions shown in Table V. Solutions h~ving two different polymers were made by dissolving ~ppropri~te Qmounts of esch polymer individuslly 8S described above. The solutions were then cooled to room ~emper~ture.
In Table V ~re summarized the eleven thermosetting composltions th~t were prep~red.
Shown ere the weight percent, b~sed on the tot~l weight of the composition, of the specific hemiformsls and polymers ln e~ch thermosettlng composition.
Ex~mple 4 The eleven thermosetting compositions prep~red in Example 3 were formulated into cured 81~ss-fiber reinforced composites.
To Compositions 9, ~nd 11 to 19 ,~ r ~., ~Le v ~nlLoro~l Co~pooltion He8l1Or~al ll ~ /phenol ~oly er ~o Iyp~ ~t ~ ~ol~ hatlo Typ~ ~t ~
g phenol 70 6 1 75 ro~t~c polre~ter 29 4 phenol 7C 1 ~7 ~roc~tlc polye~t~ 30 11 phenol 50 1 65 novol-c 50 12 phcool 66 1 1 ~ un~t polyenter 16 9S
r~ novol-c 16 95 13 phenol 66 1 1 73 un~-t polyc8ter 16.95 nGvo~c 16 95 ~ 19 phenol 66 1 1 73 ncvolrc 33.5 - 15 ph2nol ~72 3 ~t ~ un ~ poly~-t~ 16.~5 p-c;e~ol 127 7 ~t t3 U 7 1 7 novol~c lb 95 ; 1~ pbenol 173 t 3 50 1 6 novol~c 50 17 pAenol ~7~ 3 ~t t3 ~; tung oll ~1 7 ~t ~) 50 2 7 novol~c 50 - lB pbenol ~lJ 66 1 1 6 novol~c 16 95 unn~t polye8ter - ?
; 19 phenol l23 ~6 1 1.6 IlOVGlrC 16.95 uns-t polye8ter 16 95 ,'i .~ :
(1) cont-lns 7 ~tt ethylene glycol D vl-co lty reducer IZ3 cont~ln~ 7 ~t t of dlethylcn~ glycol 3~ viscG~ler reducer 1 ' ~ O
~ r' ' ' Ci~

i~
:'' ~2~0~7 hexamethylenetetramine (he~a) was mix~d with the liquid thermosettin~ compo~ition to supply additional ~ormaldehyde and to act as a catalyst by the release of ammonia. To Compo~ition 10 no hexa was added, and sodium hydroxide was added as a catalyst. The mixtures were then poured into reinforcing glass fiber. The glass fiber was non-woven glass fiber mat, Type AKM, available from PPG Industries, Inc., Pittsburgh, Penn. The mixtures were heated at about 60 to 160-C for about 15 minutes to yield a partially cured tack-free composition (B-staged). The B-staged compositions were then charged into a mold and completely cured.
In Table VI are sho~n that weight percent hexa or NaOH present in the mixture, the content of glass fiber in weight percent, the conditions of the second curing step, the cure time and the mold temperature.
Each cured composi~ion was evaluated using the above cited proceedures. The results shown in Table VII show excellent physical properties ~or these composites. Composites of high glass content such as those from numbers 18 and 19 show results superior to those of lower glass content. This demonstrates the superiority of the high-fiber composites of the invention.
Example 5 A composition having a pasty consistency comprising 60 grams of a phenol hemiformal-resole liquid reactive composition made as in Example 1, 3 grams of calcium oxide catalyst, 17 grams of calcium carbonate filler and 20 grams of chopped glass fiber was squeezed into a sheet about 1/8 inch thick ~2(~7~97 TABLE: VI

~lex~ oc Na0~1 Mold Temp Cure ~ime Fiberglass Composition twt ~) tC) tMin) ~Wt ~) 9 1.8 140-150 45 30 0.3~ 200 20 20 11 1.0 140-155 15 39 12 1.0 140-155 15 40 1~ 1.0 160 25 50 14 1.0 150 20 38 1.5 150-155 Ç0 31 16 1.0 160 30 34 1~ 1.0 140 15 30 lB 1. 0 150 25 64 19 1.0 150-155 25 57 ~ NaOH cataly~t.

D-1~824-1 t,`, ' TABLE VII
~ , .
C~po~ite Fraa Flexural Flexu~alTensile Tensile HDT Notched ~zod Canposltion ~dulus St~eng~h Modulus 5trength C (ft-lb/ln Notch) : No. (lo-6 p9i~ ~10-4 i (10-4 P~) (10 4 psi)(264 p~) 9 1.14 2.0 ------ ------ 260 4.3 1.~1 1.46 ---- ---- 82 6,4 11 0.96 1.7 1.42 1.1 250 8.
,,~. 12 1.1 2.61 O.9g 1.37 250 17 . 13 1.15 2.74 1.. 2 1.51 250 15 '16 0.96 2.09 0.89 1.26 250 8 ~,` 15 0.78 1.~1 0.64 0.77 250 10 - '' 16 0.97 1.58 0.74 0.82 250 8 17 1.0 1.,97 0.56 0.79 ~50 10 - 18 1.16 2.06 1.~8 1.~9 250 21 ,. 19 1.39 2.58 ~.29 1.69 250 21 ~'' 02 , '";' -v,' :-,,, C;~

- 49 - ~ ~V 7 between layers of polyethylene film ~nd then heated at 100C for ~0 minutes in a circulating air oven. ~The glass fiber was 1/4" chopped glass, Type 1156 avail~ble from PPG Industries, Inc., Pittsburgh, Penn.) A soft, malleable sheet was obtained which remained malleable for over 3 ~onths storage. The completely cured composite was obtained by compression molding at 150 to 175C for 5 minutes.

Claims (4)

WHAT IS CLAIMED IS:

1. A reinforced composite comprising from 20 to 70 weight percent of a reinforcing material, based in the weight of the composite, and from 30 to 80 weight percent, based on the weight of the composite, of a liquid thermosetting solution, the solution comprising:
(I) From 40 to 80 weight percent, based on the total weight of the solution, of a hemiformal composition of a phenol having any one of the formulas:
wherein n is a positive number of at least 1, b is 1 to about 5, and c is 1 to about 3, d is 0 to about 2, the sum of c and d is at least 1 and no greater than 3, the sum of c, d and x is at least 1 and no greater than 5, x is 0 to 3, R is a monovalent radical wherein x is 0 for at least 50 mole percent, based on the hemiformal compositon, of the hemiformal composition: and (II) from 20 to 60 weight percent, based on the total weight of the solution, of a polymer capable of forming solution with the hemiformal coposition of (1), said polymer being from the group; phenol-formaldehyde resoles, phenol formaldehyde novolacs, aromatic polyesters, aromatic polycarbonates, unsaturated polyesters, aromatic polyethers, urea-formaldehyde resins and melamine-formaldehyde resins.

2. A reinforced composite as in claim 1 wherein (I) of the solution is present in a concentration of from 50 to 70 weight percent, based on the weight of the solution, and (II) is present in a concentration of from 30 to 50 weight percent based on the weight of the liquid solution.

3. A reinforced composite as in Claim 1 or Claim 2 wherein the reinforcing material is present in a concentration of from 45 to 70 weight percent, based on the weight of the composite, and the solution is present in a concentration of from 30 to 55 weight percent based on the weight of the solution.

4. A reinforced composite as in Claim 1 wherein the reinforcing material is glass fiber, graphite fiber, carbon fiber or aromatic polyamide fiber.