Epoxy/thermoplastic blends: the effects of two different aromatic modifiers

• Published in: Proceedings of the Institution of Mechanical Engineers. Part L, Journal of materials, design and applications Journal of materials, design and applications, 2011-10, Vol.225 (4), p.316-326
• Main Authors: Cicala, G, Mamo, A, Latteri, A, Recca, G
• Format: Article
• Language: English
• Subjects: Blends; Epoxy adhesives; Ethers; Morphology; Phase transitions; Polymer blends; Polyphenylene oxides; Rheology; Scanning electron microscopy; Studies; Thermoplastic resins; Thermoplastics
• ISSN: 1464-4207; 2041-3076
• DOI: 10.1177/1464420711411397

In this article, a study of the properties of selected epoxy/thermoplastic blends based on the addition of two different types of aromatic modifiers is presented. The epoxy monomer used was a diglycidyl ether of biphenol A cured by 4,4′methylene bis(2,6-diethylaniline) as an amine-curing agent. One modifier was a commercial poly(2,6-dimethyl-1,4-phenylene ether or oxide) (PPE or PPO), while the other was a random copolyethersulphone synthesized in our laboratory. Several different percentages of modifiers varying from 5 to 30 wt% were considered in order to evaluate a wide spectrum of morphologies. The blends have been thoroughly characterized by parallel plate rheometry, dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM). The isothermal rheology revealed some peculiar features for the blends modified by the addition of PPO as modifier. PPO bimodal mass distribution induced a two-phase separation transitions that were not observed with blends containing copolyethersulphone. All the blends presented phase-separated morphology that was clearly observed by SEM analysis. DMTA supported the results of SEM and rheology showing multi-peak behaviour in the loss tangent curves that are typical of phase-separated systems.