| 摘要 |
1,267,984. P.V.C. compositions. KUREHA KAGAKU KOGYO K.K. 29 Aug., 1969 [31 Aug., 1968], No. 43141/69. Headings C3G and C3P. P.V.C. containing a lubricant and other additives also contains two graft copolymers of butadiene-styrene-acrylic monomer having refractive indices above and below that of the P.V.C., preferably in the ranges 1.538-1.548 and 1.530-1.541. The amounts are chosen in accordance with the other additives to give a transparent, colourless product. In the examples the additives used are dibutyl tin laurate with a lubricant chosen from ester wax, aliphatic alcohol, butyl stearate, paraffin and " Loxiol GH-2 " (Registered Trade Mark). The graft polymers used are (a) styrene, methyl methacrylate and divinyl benzene or butadiene/ styrene/divinylbenzene copolymer such that the ratio butadiene : styrene : methylmethacrylate is 46 : 38 : 16 and the divinylbenzene content is 0.5% and (b) as (a) but the final ratio is 50 : 31 : 19. |
