The curing reaction of poly(ether-sulfone)-modified epoxy resin

✍ Scribed by Yung-Sin Chen; Jun-Shen Lee; Tzyy-Lung Yu; John-Chang Chen; Wen-Yih Chen; Min-Chin Cheng

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 589 KB
• Volume: 196
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1995.021961102

✦ Synopsis

Abstract

One of the useful methods to improve the toughness of epoxy resin is by mixing the resin with poly(ether‐sulfone) (PES). In the present work, two hydroxyl‐terminated PESs with molecular weights M~n~ = 28 600 and 4 200 were used for blending with epoxy resin. The curing reaction of diglycidyl ether/bisphenol‐A (DGEBA) with 4,4′‐diaminodiphenyl sulfone (DDS) in the presence of hydroxyl‐terminated PES was studied by means of differential scanning calorimetry (DSC) and gel‐permeation chromatography (GPC). For the DGEBA‐DDS‐PES system with a stoichiometric ratio of epoxy and amino groups the DSC experimental results showed that at a fixed molecular weight of PES the curing reaction rate decreases with increasing PES concentration. At a fixed PES concentration (in the range of between 0 and 20 wt.‐% of PES), the DGEBA‐DDS system modified with hydroxyl‐terminated PES with lower molecular weight had a faster curing reaction rate at low conversion and a slower curing reaction rate at high conversion. The GPC results showed the evidence of etherification between low‐molecular‐weight PES with epoxy resin. However, very little etherification of high‐molecular‐weight hydroxyl‐terminated PES with epoxy resin was found. Based on the experimental results, a curing reaction mechanism of DGEBA with DDS in the presence of hydroxyl‐terminated PES is proposed.