GB797270A - Improvements in transesterification catalysts - Google Patents

Abstract

Transesterification reactions are catalysed by a phenol represented by either of the formul <FORM:0797270/IV (b)/1> and <FORM:0797270/IV (b)/2> where R1 is alkyl, cycloalkyl or aryl; R2 and R3 each are hydrogen, alkyl, cycloalkyl or aryl; and R4 is alkylene, cycloalkylene or arylene. The proportion of catalyst generally ranges from about 0.1 to about 5 per cent based on the weight of the carboxylic acid used to prepare the ester. Phenols specified include: 2,21-methylene - bis - (4 - methyl - 6 - t - butylphenol); 2,21 - methylene - bis - (4 - ethyl - 6 - t - butyl - phenol); 2,4 - dinonylphenol; 2,6 - dinonyl-phenol; 2,4,6 - trinonylphenol; 2,6 - di - t - butyl 4 - cresol; 2,4 - didodecylphenol; bis-(2-hydroxy - 3 - t - butyl - 5 - methylbenzyl) durene; 2,6 - dicyclohexyl - 4 - cresol; 2 - cyclohexylphenol; 2,21 - methylene - bis - (6 - cyclopentylphenol); 2,21 - methylene - bis - (4 - methyl-6-cyclopentylphenol); 2 - phenylphenol; 2,6-diphenyl - 4 - cresol; 2,21 - propylene - bis - (4-methyl - 6 - phenylphenol); 2,4 - dinonyl - 6 - methylphenol; 2,4 - di - t - butyl - 6 - methylphenol. In Example (2) n-hexyl stearate is prepared by reacting methyl stearate with n-hexanol in the presence of 2,21-methylene-bis-(4 - methyl - 6 - t - butylphenol. In Example (1) bis-(b -hydroxyethyl) adipate is prepared from adipic acid and ethylene glycol conventionally prior to conversion to a polyester by the process of the invention (see Group IV (a)).ALSO:Polyesters are prepared from esters of dicarboxylic or polycarboxylic acids with glycols or polyhydroxy compounds using as catalyst a phenol represented by either of the formulae <FORM:0797270/IV (a)/1> where R1 is alkyl, cycloalkyl or aryl; R2 and R3 each are hydrogen, alkyl, cycloalkyl or aryl; and R4 is alkylene, cycloalkylene or arylene. The proportion of catalyst is generally about 0.1 to 5 per cent based on the weight of the carboxylic acid used to prepare the ester. Phenols specified include: 2,21 - methylene - bis (4 - methyl - 6 - t - butylphenol); 2,21 - methylbis - (4 - ethyl - 6 - t - butylphenol); 2,4-dinonylphenol; 2,6 - dinonylphenol; 2,4,6-trinonylphenol; 2,6 - di - t - butyl - 4 - cresol; 2,4-didodecylphenol: bis - (2 - hydroxy - 3 - t - butyl5 - methylbenzyl) durene; 2,6 - dicyclohexyl-4-cresol; 2 - cyclohexylphenol; 2,21 - methylene-bis - (4 - methyl - 6 - cyclopentylphenol); 2,21-methylene - bis - (6 - cyclopentylphenol); 2-phenolphenol; 2,6 - diphenyl - 4 - cresol; 2,21-propylene - bis - (4 - methyl - 6 - phenylphenol); 2,4 - dinonyl - 6 - methylphenol; 2,4 - di - t - butyl - 6 - methylphenol. Dicarboxylic acids which may be used in the starting material esters are succinic, glutaric, adipic, pimelic, suberic, azelaic, sebacic, dilinoleic, octadecanedicarboxylic acid, phthalic, maleic, fumaric and derivatives such as -ethylsuberic or a ,a 1-diethyl adipic acid. Polycarboxylic acids include tricarballylic, aconitic, citric and linoleic. Suitable glycols include ethylene, propylene, butylene, pentylene, 2,2-dimethyl-1,3-propylene, hexylene, dilinoleyl and 1,12-octadecylene glycols. Polyhydroxy compounds, such as glycerol, sorbitol, pentaerythritol and triethanolamine may be used and also alkylene oxide polymers, such as diethylene, triethylene, dipropylene, polyethylene, polypropylene, polybutylene glycols and poly - 3 - chloro-1,2-propylene ether glycol. In examples, polyesters are prepared from: (1) - bis - (b - hydroxyethyl) adipate using as catalysts 2,21-methylene - bis - (4 - methyl - 6 - t - butylphenol), a mixture of dinonyl- and trinonylphenol, and 2,6 - di - t - butyl - 4 - methylphenol; (4) a reaction product of adipic acid, diethylene glycol and 2 - methylol - 2 - methyl - 1,3 - propanediol using 2,21 - methylene - bis - (4 - methyl - 6 - t - butylphenol) as catalyst.