摘要 |
<p>Copolymers of BPA and menthane bisphenols such as BPT1 and BPT2 can be used as a compatabilizer to allow the formation of homogeneous blends of BPA with menthane bisphenol polycarbonates such as poly-BPT1 or poly-BPT2 or copolymers thereof. Thus, a compatible polycarbonate blend is made by combining a bisphenol A polycarbonate, a menthane bisphenol polycarbonate and a BPA/menthane bisphenol copolymer compatabilizer, and mixing the combined materials to form a blend. The compatabilizer may contain one or more species of methane bisphenol. In a specific example, BPT1 and BPT2 are used in the compatabilizer in a ratio, BPT1/BPT2, in the range of 70/30 to 10/90, preferably less than or equal to 1/1, for example around 30/70. By adjusting the relative amounts and the properties of the bisphenol A polycarbonate and the methane bisphenol polycarbonate, the glass transition temperature and the toughness of the blend can be selected.</p> |