GB419604A - Manufacture of synthetic resins - Google Patents

Abstract

Synthetic resins are prepared by heating together a polybasic acid and a polyhydric alcohol having in the molecule at least five carbon atoms and two or three --CH2OH groups attached to a single carbon atom. Fatty oils and monohydric alcohols or acids may also be present. In examples: (1) phthalic anhydride is condensed with dimethylol dimethylmethane to give a resin soluble in alcohol-toluol mixtures acetone and ethyl acetate and compatible with pyroxylin. If desired a portion of the polybasic acid may be replaced by a fatty acid, fatty oil acids, natural acidic gum or mixtures such as linseed oil acids and rosin. (2) 2 : 2 : 6 : 6 - Tetramethylolcyclohexanol is condensed with phthalic anhydride and oleic acid. (3) Ethyltrimethylolmethane is condensed with phthalic anhydride and linseed oil acids. (4) Amyltrimethylolmethane is condensed with phthalic anhydride and cotton seed oil acids giving a product soluble in xylol, ethyl lactate and readily compatible with nitrocellulose. (5) Ethyltrimethylolmethane is condensed with rosin and phthalic anhydride. giving a product soluble in acetone and which may be blended with drying oils. In the above examples the monobasic acids may be replaced by their glycerides or esters with other polyhydric alcohols. (6) Linseed oil and dimethylol dimethylmethane are heated together and the product condensed with phthalic anhydride to give a resin soluble in hydrocarbons, butyl alcohol, esters and ketones and compatible with nitrocellulose, ethyl cellulose and benzyl cellulose. (7) Linseed oil acids, chinawood oil acids, dimethylol dimethylmethane and phthalic anhydride are condensed in the presence of a hydrocarbon mixture giving a product which may be thinned with esters, ketones, alcohols or hydrocarbons as desired and used with or without the addition of nitrocellulose. (8) A mixture of ethyltrimethylolmethane and benzyl alcohol is condensed with adipic acid to give a product soluble in alcohol-toluol mixtures, ethyl acetate, xylol and dioxane and compatible with nitro cellulose, cellulose nitroacetate and ethyl acetate. The alcohol used in examples 1, 6 and 7 may be replaced in part by ethylene glycol whilst the alcohol used in examples 3, 5 and 8 may be replaced in part by glycerol. (9) Chinawood oil acids, ethyltrimethylolmethane, glycerol and phthalic anhydride are condensed to give a product soluble in toluol, butyl alcohol or acetate and mixtures of ethyl alcohol with toluene or aliphatic hydrocarbons and compatible with nitrocellulose. (10) Adipic acid, dimethylolquinaldine (a -quinolylpropanediol) and ethylene glycol are condensed together in the presence of chlorobenzene giving a resin soluble in hydrochloric acid. In general suitable polybasic acids include succinic, sebacic, fumaric, tartaric, citric, dilactylic, thiodilactylic, salicylacetic, diphenic, naphthalic, pyromellitic, tricarbyllylic, hexahydrophthalic, quinolinic acids. Suitable polyhydric alcohols for use to replace part of the special alcoholic compounds include glycerol, ethylene glycol, propylene glycol, butylene glycol, diethyleneglycol, polyvinyl alcohol and polyhydric ether alcohols such as monoalkyl or aryl ethers of glycerol. Suitable monobasic fatty acids include oleic, butyric, stearic, lauric, lactic, benzoic, benzoylbenzoic salicylic, linseed oil, cotton seeed oil, chinawood oil, soya bean oil, perilla oil and coconut oil acids. Suitable monohydricalcohols include benzyl, N - butyl, ceryl, cetyl and cyclohexyl alcohols. Suitable gums include rosin, pontianac, kauri or congo in the natural or esterified state such as ester gum or ethyl abietate. Fatty oils include linseed, chinawood, soya bean, fish, castor, coconut, cottonseed and rubber seed oils. The products are useful as coatings with or without the addition of cellulose derivatives such as cellulose acetate, nitrate, acetopropionate, ethyl and benzyl cellulose, natural resins such as rosin, kauri, damar, ester gum and ethyl abietate; drying oils such as linseed and chinawood oils; synthetic resins such as phenol-formaldehyde, amine-aldehyde and polyvinyl resins; bitumens and asphalts. Pigments, fillers, lakes, plasticizers, antioxidants and solvents may also be added. The products may also be used as binders or cements; moulding plastics; impregnating and coating agents for paper, fabrics, porous stone etc.; adhesive layer in the manufacture of safety glass; binders for cellulose acetate and mica; and in the preparation of laminated products. The polyhydric alcohols may be prepared in general by condensing formaldehyde with aldehydes and ketones having at least three carbon atoms and one or more hydrogen atoms in the a -position to the carbonyl group. The aldehydes have the general formula <FORM:0419604/IV/1> where R1 is a monovalent hydrocarbon radical and R2 hydrogen or a monovalent hydrocarbon radical. Thus trimethylolmethylmethane is derived from propionaldehyde, trimethylolethylmethane from butyraldehyde, dimethyloldimethylmethane from iso-butyraldehyde, amyltrimethylolmethane from heptaldehyde, methylethyldimethylolmethane from 2-methylbutyraldehyde and trimethylolphenylmethane from phenylacetaldehyde. Typical ketones have the formula <FORM:0419604/IV/2> where R1 is a monovalent hydrocarbon radical and R2 hydrogen or a monovalent hydrocarbon radical. Suitable ketones for use include acetone, methyl ethyl ketone, diethyl ketone, butyrone, benzalacetone and acetophenone. The completely saturated products such as hexamethyloldi-iso-propyl ketone (derived from acetone) tend to form dehydration products and also tend to polymerise. Hexamethyloldi-iso-propyl ketone dehydrates to fesin anhydroenneaheptite which is a suitable alcohol for the process. Ketones wherein R1 and R2 are linked to form part of a ring containing at least three carbon atoms such as those of the general formula <FORM:0419604/IV/3> wherein R is an alkylene or substituted alkylene radical such as ethylene, butylene, propylene, trimethylene or amylene. 2 : 2 : 6 : 6 - tetramethylolcyclohexanol and the corresponding 3-methyl derivative are derived from cyclohexanone and 3-methylcyclohexanone; 2 : 2 : 5 : 5 - tetramethylolcyclopentanol from cyclopentanone and 2 : 2 : 4 : 4 - tetramethylolcyclobutanol from cyclobutanone. A further type of alcohols or ketones that may be used are those of the formula <FORM:0419604/IV/4> wherein R2 is hydrogen or a monovalent hydrocarbon radical and R1 an alkylidene radical of at least two carbon atoms such as ethylidene, propylidene and isoamylidine. Ethyltrimethylolmethane is derived from crotonaldehyde and other alcohols may be derived from methyl propenyl ketone and b -ethylacrolein. Other suitable alcohols may be derived from pyridine homologues such as a -picoline and quinaldine by condensing formaldehyde with the alkyl (especially a and g -) derivatives of pyridine, quinoline or derivatives thereof such as lepidine, a -pipecoline, lutedines and collidines to give di- and trimethylol picolines and quinaldines. Further suitable alcohols may be obtained from substituted aldehydes and ketones such as diacetone alcohol, levulinic acid, diacetyl, \su-chlorobutyraldehyde and b -ethoxyvaleraldehyde.