| 摘要 |
1507745 Fillers UNION CARBIDE CORP 4 June 1975 [5 June 1974 14 April 1975] 24149/75 Heading C1A [Also in Division C3] A filler suitable for use in polymer composition is made by contacting in the presence of water a metal carbonate or sulphate or mixture thereof wherein the metal is Ba, Ca. Mg. Zn. Sr. Be or mixtures thereof with a precipitated, undried water-insoluble metal silicate wherein the metal is Al, Ba. Be, Cd, Ca, Co, Cu, Fe, Pb, Li, Mg, Mn, Hg, Ni, Ag, Sr, Sn. Zn, Zr or a rare earth metal having an atomic number of 57-71 inclusive or mixtures thereof, the amount of silicate employed ranging from 0À1-20 parts by weight per 100 parts of the mineral, drying the silicate salt on the surface of the sulphate/carbonate and then treating with an organo silane coupling agent of formula: wherein R, which contains a carbon atom directly bonded to Si, is a functionally substituted organic radical, R' is R or a monovalent hydrocarbon radical, a is 0 or 1 and X is a hydrolysable group, a hydrolysate of said silane, a condensate of said silane or a mixture thereof. The metal/oxide ratio of the silicate is preferably less than 3.1. The silicate is preferably precipitated in the presence of the mineral. The coupling agent is suitably used in amounts of 0À1-10 parts by weight per 100 parts by weight of the modified mineral and a number of suitable coupling agents are specified. |
