PROCEDURE FOR PREPARING MODIFIED EPOXIDIC RESINS THAT HAVE A DISTRIBUTION OF MOLECULAR WEIGHTS.

摘要

A PROCESS TO PREPARE A MODIFIED EPOXY RESIN WITH A MOLECULAR WEIGHT DISTRIBUTION BETWEEN 1.9 AND 4.5 AND AN EPOXY GROUP CONTENT LESS THAN 200 MMOL / KG REACTING A TEMPERATURE OF BETWEEN 135 AND 215 C WITH AN AROMATIC EPOXY RESIN WITH A EPOXY OF AT LEAST 250 MMOL / KG AND BETWEEN 1.5 AND 2.2 EPOXY GROUPS PER MOLECULA WITH BETWEEN 5 AND 170% MOLAR EXCESS OF A DIHYDROXY COMPOUND OF FORMULA; IN WHICH R IS HYDROGEN OR ALKYL C SUB 1-C SUB 4 AND N IS A NUMBER BETWEEN 1 AND 4, IN THE PRESENCE OF AN ETERIFICATION CATALYST CHOSEN BETWEEN STANNOSE HALIDES AND STANDARD CARBOXYLATES.