Patent GB-756699-A (GB)
Title: Improvements in or relating to lubricating oil composition
IPC: C10L1/18
Filed: 1954-03-16
Abstract: Polymers of molecular weight at least 1000 are obtained by polymerizing, with or without a simple ester, a complex ester containing no free carboxyl or hydroxyl groups and derived from a glycol, an unsaturated aliphatic dibasic acid and a saturated, aliphatic, monohydric alcohol containing at least 8 carbon atoms. Unsaturated dibasic acids exemplified are fumaric, maleic, itaconic, citraconic and mesaconic.  Specified esters have the formula R11OOC-R-COOR1-CO-R-COOR11 wherein R is an unsaturated aliphatic hydrocarbon radical having 2 to 5 carbon atoms, R11 is a saturated aliphatic hydrocarbon radical of at least 8 carbon atoms and R1 is <FORM:0756699/IV(a)/1> where m is from 0 to 10, n is 1 to 10 and p is 1 to 5.  Suitable simple esters are the diesters of unsaturated dibasic acids and aliphatic monohydric alcohols (e.g. "Lorol" (Registered Trade Mark) fumarate), vinyl and allyl acetates, butyrates, octoates, laurates, stearates and coconut oil esters, and allylidene diacetate.  Catalysts which may be used are benzoyl and acetyl peroxides, t-butyl hydroperoxide and t-butyl perbenzoate.  An inert solvent such as mineral oil, light hydrocarbon solvent, naphtha or carbon tetrachloride may be used to control molecular weight.  The products are useful as pour depressants and viscosity index improvers, e.g. for paraffinic oils, and may also be added to greases, paraffin wax and diesel fuel.ALSO:Polymerizable complex esters containing no free carboxyl or hydroxyl groups are derived from a glycol, an unsaturated aliphatic dibasic acid and a saturated, aliphatic, monohydric alcohol containing at least 8 carbon atoms. Specified esters have the formula R11OOC-R-COOR1-OC-R-COOR11, wherein R is an unsaturated aliphatic radical of 2 to 5 carbon atoms, R1 is <FORM:0756699/IV(a)/1> where m is 0 to 10, n is 1 to 10 and p is 1 to 5, and R11 is a saturated aliphatic radical of at least 8 carbon atoms.  The complex esters may be prepared by esterifying 2 mols. of dibasic acid with 1 mol. of glycol followed by further esterification with 2 mols. of monohydric alcohol.  A mixture containing simple ester may be obtained by using an excess of dibasic acid and then adding sufficient monohydric alcohol to esterify the free carboxyl groups of the glycol half ester and the excess dibasic acid.  The complex ester or mixture is polymerized to give polymers useful as additives for lubricating oils (see Groups IV (a) and III). Compounds used in preparing the complex and simple esters are maleic, itaconic, citraconic, mesaconic and fumaric acids; ethylene, polyethylene, propylene, di-, tri- and tetra-propylene, trimethylene, pentamethylene, butylene and octylene glycols; and octyl, decyl, cetyl, lauryl, tetradecyl, octadecyl and mixed (e.g. "Lorol" (Registered Trade Mark)) alcohols.  In examples the components are refluxed in toluene using sodium bisulphate as catalyst.ALSO:Lubricating compositions comprise polymers of complex esters containing no free carboxyl or hydroxyl groups and derived from a gycol, an unsaturated aliphatic dibasic acid and a saturated, aliphatic, monohydric alcohol of at least 8 carbon atoms. Specified esters have the formula R11OOCR -COOR1-COR -COOR11 wherein R is an unsaturated aliphatic radical having 2 to 5 carbon atoms, R11 is a saturated aliphatic radical of at least 8 carbon atoms and R1 is <FORM:0756699/III/1> where m is 0 to 10, n is 1 to 10 and p is 1 to 5.  Copolymers with simple esters (e.g. Lorol fumarate (the word "Lorol" is a registered Trade Mark) and vinyl acetate) may also be used (see Group IV(a)).  The polymers are pour point depressants and viscosity index improvers for paraffinic type oils and may also be added to soapthickened greases, paraffin wax and diesel fuel. Optional additives are dyes, antioxidants, extreme pressure agents, rust inhibitors and other pour depressants and viscosity index improvers.