| 摘要 |
<p>Thermoplastic transparent polyamides, with a relative viscosity >=1.5 (1g in 100g m-cresol at 25 degrees C) have the formula: (where R is and are formed by the polycondensation of bis-(4-aminocyclo hexyl)-methane having 40-70% of the cyclohexyl rings with trans orientation, with a dicarboxylic acid mixture contg. 5-100 (pref. 75-100) moles% of 3-ethyl-1,10-decane-dicarboxylic acid and 0-95% (pref. 0-25) mole % of one or more additional 6-16C dicarboxylic acids. The condensation takes place in the molten state at a temp. of 180-240 degrees C under atmospheric or normal stream pressure; water is distilled off, and the reaction continued at 240-320 degrees C usually under vacuum. The polyamides have good colour, mechanical properties and moisture resistance.</p> |
