The polyamides according to the invention are mainly transparent (amorphous), but in some cases also partially crystalline. They have a reduced specific viscosity (0.5% in m-cresol at 25.degree. C.) of at least 0.3 dl/g, and consist of recurring structural elements of the formula I ##STR1## in which R.sub.1 and R.sub.2 are monovalent aliphatic or cycloaliphatic radicals, and Z is a bivalent aliphatic radical. The dicarboxylic acid structural radicals are derived in particular from adipic acid. The polyamides have high glass transition temperatures, and have a low water absorption and also good stability to hydrolysis. They can be processed into moulded articles (for example by the injection moulding process and extrusion process).
本发明的聚酰胺主要是透明(无定形),但在某些情况下也部分结晶。它们具有降低的比旋度(在25°C下0.5%的m-
甲醇中)至少为0.3 dl/g,并由公式I的重复结构单元组成:
##STR1##
其中R1和R2是一价的脂肪族或环烷基,Z是一价的脂肪基。二
羧酸结构基尤其来自
己二酸。该聚酰胺具有高
玻璃化转变温度,并具有低吸
水性和良好的耐
水解稳定性。它们可以通过注塑成型和挤出成型等工艺加工成成型品。