Patent GB-847630-A (GB)
Title: New polyesters and their method of preparation
IPC: C07C69/34
Filed: 1957-08-30
Abstract: The invention comprises liquid polyesters, and mixtures thereof, having the general formula <FORM:0847630/IV(a)/1> wherein n is an integer, R represents a C4-18 alkyl group and R1 represents an alkylene group containing 2-14 carbon atoms.  Different R and R1 groups may be present in the one ester molecule.  The preferred esters have viscosities of 50-50,000 centistokes at 25 DEG  C.  The esters are prepared by reacting in one or more stages (a) an acid or acids of the formula HOOC.R1.COOH, or the anhydrides thereof where they exist, (b) a saturated monohydric alcohol or alcohols ROH and (c) 2-methyl-2-ethyl- 1 : 3-propanediol; the molar proportion of the diol should be at least half the molar proportion of alcohol(s) and the total molar proportion of alcohol(s) and diol should exceed the molar proportion of acid(s).  Specified alcoholic and acidic reagents are 2-ethyl hexyl, 2-ethyl butyl, cetyl, neopentyl, trimethyl hexyl and trimethyl nonyl alcohols and sebacic, adipic, pimltic, suberic, azelaic and brassylic acids. In an Example, a polyester is formed from the diol, 2-ethyl hexyl alcohol and sebacic acid.  The esters may be used in synthetic lubricants and as plasticisers.  According to the Provisional Specification R and R1 are not restricted to the above specified carbon contents and succinic and glutaric acids are named reagents.  Specifications 687,346, 824,249 and 847,629 are referred to.ALSO:The invention comprises liquid polyesters of the general formula: ROOC. R1. COO [CH2 C.(CH3) (C2H5) CH2 OOC. R1 COO]n R wherein n is an integer, R represents a C4-18 alkyl group and R1 a C2-14 alkylene group.  Different R and R1 groups may be present in a single ester molecule.  The preferred esters have viscosities of 50-50,000 centistokes at 25 DEG  C.  The esters are prepared by reacting in one or more stages (a) one or more acids HOO C. R1.COOH, (b) one or more saturated monohydric alcohols ROH and (c) 2-methyl-2-ethyl-propane-1 : 3-diol, the molar proportion of the diol being at least half the molar proportion of alcohol (s) and the total molar proportion of alcohols (s) and diol exceeding the molar proportion of acid (s). Specified alcohols and acids are 2-ethyl hexyl, 2-ethyl butyl, cetyl, neopentyl, trimethyl hexyl and trimethyl nonyl alcohols and sebacic, suberic, pimelic, azelaic, adipic and brassylic acids. In an Example a mixture of azelaic acid, the diol and 2-ethyl hexanol is heated under nitrogen at 210 DEG C., distilling alcohol being recycled and the pressure is then reduced until an acid value of less than 1 mg. KOH is reached.  The esters may be used as synthetic lubricants or plasticisers.  According to the Provisional Specification R represents the hydrocarbon radical of any aliphatic monohydric alcohol and R1 the hydrocarbon radical of any aliphatic dicarboxylic acid, e.g. succinic or glutanic acid. Specifications 687,346, 824,249 and 847,629 are referred to.ALSO:Synthetic lubricants comprise liquid polyesters, or mixtures thereof, of the general formula ROOC.R1.COO[CH2.C(CH3)(C2H5) CH2OOC.R1.COO]nR wherein n is an integer, R represents a C14-C18 alkyl group and R1 represents an alkylene group containing 2-14 carbon atoms. Different R and R1 groups may be present in a single ester molecule and n may have a fractional value.  The preferred esters have viscosities of 50-50,000 centistokes at 25 DEG C. Specified alcoholic and acidic reagents for preparing the esters are 2-ethyl hexyl, 2-ethyl butyl, cetyl, neopentyl, trimethyl hexyl and trimethyl nonyl alcohols and sebacic, adipic, pimelic, suberic, azelaic and brassylic acids.  A specified polyester is derived from the diol 2-methyl 2-ethyl propane-1 : 3-diol, 2-ethyl hexanol and sebacic acid.  According to the Provisional Specification R and R1 are not restricted to the above specified carbon contents. Specifications 687,346, 824,249 and 847,629 are referred to.