Patent GB-752010-A (GB)
Title: Lubricant composition
Filed: 1954-04-15
Abstract: A lubricating composition comprises (a) a liquid organopolysiloxane having the general formula <FORM:0752010/IV(a)/1> , where n has an average value of 2.0-2.9 and each R is a methyl, monocyclic aryl or halogenated aryl radicle, at least 37 per cent of the total number of R radicles in the organopolysiloxane being methyl radicles; and (b) 0.25-5 per cent by weight, based on the organopolysiloxane, of a halogenated fatty acid having 1-12 carbon atoms in the molecule.  R in the general formula may be chosen from methyl, phenyl, tolyl, iodotolyl, dichlorophenyl, heptachloroxenyl, dichloroxenyl, bromophenyl and dibromoxenyl radicles.  Suitable halogenated fatty acids are dichloroacetic, a  - bromocaproic, trichloro - acetic, a  - chloropropionic, a -bromopropionic, a -bromobutyric, a -chlorovaleric, iodo-acetic, b -chloropropionic, a ,b -dichlorobutyric, g -bromovaleric, bromocapric, chlorocapric, chlorolauric and bromolauric acids.  The lubricating composition may be thickened to a grease structure by admixture with a thickening agent and may also contain antioxidants.  Suitable thickening agents are metallic salts of higher fatty acids such as lithium stearate, graphite, clay, carbon black, silica gels and fumed silica.  In the examples, lubricating compositions are described consisting of (i) trimethyl siloxy endblocked dimethyl siloxane polymer and a halogenated fatty acid chosen from dichloro-acetic, trichloro-acetic, a -bromocaproic, a -chloro- or bromo - propionic, b  - chloropropionic and a  - bromobutyric acids; (ii) a -bromobutyric acid and a liquid organopolysiloxane composed of C6H5CH3SiO, (CH3)2SiO and (CH3)3SiO1/2 units; C6H5CH3SiO, (CH3)2SiO, (CH3)3SiO1/2 and dichlorophenyl siloxane units; and C6H5CH3SiO and (CH3)3SiO1/2 units; and (iii) di-iodo-acetic acid and a liquid organopolysiloxane composed of C6H5CH3SiO, (CH3)2SiO, (CH3)3SiO1/2 and dichlorophenyl siloxane units.  Specifications 667,179, 668,166, [Group XXXVI], and 719,912 are referred to.ALSO:A lubricating composition which, besides being suitable for use at high and low temperatures, also compares favourably with petroleum oil at ordinary temperatures, comprises (a) a liquid organopolysiloxane having the general formula <FORM:0752010/III/1> where n has an average value of 2.0-2.9 and each R is a methyl, monocyclic aryl or halogenated aryl radicle, at least 37 per cent of the total number of R radicles in the organopolysiloxane being methyl radicles and (b) 0.25-5 per cent by weight, calculated on the organopolysiloxane, of a halogenated fatty acid having 1-12 carbon atoms in the molecule.  R in the general formula may be chosen from methyl, phenyl, tolyl, iodotolyl, dichlorophenyl, heptachloroxanyl, dichloroxenyl, bromophenyl and dibromoxenyl radicles.  Suitable halogenated fatty acids are dichloro-acetic, a-bromocaproic, trichloro-acetic, a-chloroproprionic, a-chlorobromopropionic, a-bromobutyric, a-chlorovaleric, iodo-acetic, b -chloroproprionic, a, b  - dichlorobutyric, g -bromovaleric, bromocapric, chlorocapric, chlorolauric and bromolauric acids.  The lubricating composition may be thickened to a grease structure by admixture with a thickening agent and may also contain antioxidants.  Suitable thickening agents are metallic salts of higher fatty acids such as lithium stearate, graphite, clay, carbon black, silica gels and fumed silica.  In the examples, lubricating compositions are described consisting of (i) trimethyl siloxy end-blocked dimethylsiloxane polymer and a halogenated fatty acid chosen from dichloro-acetic, trichloroacetic, a-bromocaproic, a-chloro- or bromoproprionic, b -chloroproprionic and a-bromobutyric acids, (ii) a-bromobutyric acid and a liquid organopolysiloxane composed of C6H5CH3SiO (CH3)2SiO and (CH3)3SiOy2 units; C6HH5CH3SiO, (CH3)2SiO, (CH3)3-SiOy2 and dichlorophenylsiloxane units; and C6H5CH3SiO and (CH3)3SiOy2 units and (iii) di - iodo - acetic acid and a liquid organopolysiloxane composed of C6H5CH3SiO, (CH3)2SiOy2 and dichlorophenylsiloxane units. Specifications 667,179, 668,186 [Group XXXVI] and 719,912 are referred to.