DYNAMIC-MECHANICAL PROPERTIES OF SEMIINTERPENETRATING NETWORKS BASED ON POLY(STYRENE-CO-MALEIC ANHYDRIDE) - .3. POLY(2,6-DIMETHYL-1,4-PHENYLENE ETHER)-CROSS-POLY(STYRENE-CO-MALEIC ANHYDRIDE)

Semi-IPN's based on linear poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and diamine crosslinked poly(styrene-co-maleic anhydride) (PScoMA) copolymers containing small amounts of maleic anhydride (PSA = 4.7 wt.-% MA, PSB = 5.8 wt-% MA) are studied with respect to the influence of cross-linking on the phase behavior. Temperature-dependent dynamic mechanical analysis (DMA) and DSC show that the semi-IPN's prepared from concentrated solution show weak crystallinity of the PPE phase. After heating above the PPE melting transition the semi-IPN's remain amorphous and the relaxation in the glass transition region as well as the terminal relaxation of the free PPE chains in the network is studied as a function of PPE concentration and network density.