| 摘要 |
<p>1409857 Polycarbonate compositions BAYER AG 4 Oct 1973 [5 Oct 1972] 46327/73 Heading C3R A polycarbonate composition comprises (a) 10-95 p.b.w. of a polycarbonate of recurring units of the Formula (I) where X is -CH 2 -, -C(CH 3 ) 2 - or -(CH 3 ) 2 C-C 6 H 4 -C(CH 3 ) 2 -, and (b) 90-5 p.b.w. of a polycarbonate of recurring units of the Formula (II) which optionally can be replaced in part by units of the Formula (III) where Y is Cl or Br, there being at least 2 units of Formula (II) per unit of Formula (III). The polycarbonates generally have an average molecular weight above 20,000. The composition may contain up to 40 p.b.w. of glass fibres. The compositions may be made either by mixing granules of polycarbonates (a) and (b) and then extruding the mixture on a single- or multiscrew extruder; or by mixing the polycarbonates (a) and (b) in solution, e.g. in CH 2 Cl 2 , and then evaporating off the solvent. In the examples it is shown that the polycarbonate mixtures are (i) transparent, (ii) have only one glass transition temperature, (iii) show improved stability to saponification, (iv) have improved impact strength, (v) their solution and melt viscosity do not increase during thermoplastic processing in the presence of atmospheric oxygen, (vi) are fire-resistant when the polycarbonate component (b) contains cocondensed units of Formula (III), (vii) have improved tracking resistance and (viii) have high structural viscosity. Uses.-Mouldings; films; fibres; coatings.</p> |
