| 摘要 |
1,228,493. Polyester-based moulding composition. FARBWERKE HOECHST A.G. 8 Nov., 1968 [9 Nov., 1967], No. 52970/68. Heading C3R. A polyester-based thermoplastic moulding composition having a reduced specific viscosity (in 1% solution in 60: 40 by weight phenol: tetrachloroethane at 25‹ C.) of from 1À0 to 1À5 dl./g. is made by mixing together at least two polyethylene terephthalates each having a reduced specific viscosity of from 0À5 to 2À0 dl./g., which differ by 0À02 to 1À0 units. Each polyethylene terephthalate may contain, in addition, units of isophthalic, naphthalene - 2,6 - dicarboxylic or adipic acids and/or neopentyl glycol, butane - 1,4 - diol, or 1,4 - dimethylolcyclohexane. The composition may also contain 0À005 to 0À5% by weight of a finely divided inorganic substance or organic polymer such as calcium carbonate, aluminium silicate, talc, soot, polyethylene or polypropylene, whose particle size is at most 2 microns, and/or paraffin wax or another wax. Examples (2) to (5) describe making such a composition by mixing compositions of the separate polyethylene terephthalates with the above auxiliary additives, in a tumbling drier. |
