Fluoroalkylpolysiloxane lubricants containing organophosphorus additives

1,198,281. Organopolysiloxane lubricants. DOW CORNING CORP. 20 June, 1967 [13 July, 1966], No. 28390/67. Heading C3T. [Also in Division C5] A lubricating composition consists essentially of a mixture of (1) 100 parts by weight of an organopolysiloxane liquid containing at least 70 mol. per cent of (R f CH 2 CH 2 )CH 3 SiO units, any other units present being (RSiO 3/2 ), (R 2 SiO) or (R 3 SiO 1/2 ), where R f is a perfluoroalkyl radical containing not more than 12 carbon atoms and R is a monovalent hydrocarbon or halohydrocarbon radical; and (2) from 0À5 to 8 parts by weight of a compound selected from R n H 3-n PO 4 , R n H 3-n PO 3 , where R is as defined above and n is 2 or 3. A preferred compound (1) is a polymer of 3,3,3- trifluoropropylmethylsiloxane which has endblocks of the formula (R 3 SiO 1/2 ); preferred organophosphorus additives (2) include tris-(2- ethylhexyl)-phosphate, tributyl phosphate, tricresyl phosphate and di-isopropyl hydrogen phosphate. A solubilizing agent such as glycerol trioctoate may be added.