| abstract |
PURPOSE: To improve heat resistance, thermal stability of the melt dwelling in a molding machine, water resistance, and weatherability by melt polycodensing an arom. dihydroxyl compd. with a carbonic diester and neutralizing the resulting polycondensate with an acidic compd. n CONSTITUTION: 1mol of an arom. dihydroxyl compd. [e.g. 2,2-bis(4- hydroxyphenyl)propane], 1.0-1.30mol of a carbonic diester (e.g. diphenyl carbonate), and, if necessary, 0.001-0.02mol of a polyfunctional compd. having at least 3 functional groups in the molecule [e. g. 1,1,1-tris(4-hydroxyphenyl)ethane] are melt polycondensed at 80-250°C for 0-5 hr in the presence of 10 -4 mol or lower of an alkaline catalyst (e.g. NaOH) and further polycondensed under a reduced pressure of 5mmHg or lower at 240-320°C to give a polycondensate, which is neutralized with an acidic compd. (e.g. Broensted acid). n COPYRIGHT: (C)1992,JPO&Japio |