Polyphenylene Ether Macromolecules. VII. Performance in t-Butyl Styrene/Divinyl Benzene Resin System

摘要

Methacrylate terminated polyphenylene ether macromonomer (M-PPE-M) was used to enhance the performance of free radical cured thermoset compounds. The t-butyl styrene (TBS)/divinyl benzene (DVB) was chosen as a model system. TBS was chosen because of its lower vapor pressure, lower heat of reaction, and lower shrinkage during polymerization compared to styrene and p-methylstyrene. In addition, poly t-butylstyrene exhibits a high glass transition temperature (T_g), low density, and low dielectric properties. Both DVB and M-PPE-M were evaluated as crosslinking agents. Solubility and swelling of TBS/DVB and TBS/M-PPE-M castings in toluene were used to study efficiency of crosslinking. DVB and M-PPE-M were effective in crosslinking TBS and showed increased T_gS. However, DVB decreased toughness and M-PPE-M showed a significant increase in toughness. TBS/M-PPE-M gave a unique combination of high compressive strength and yielding under compressive testing. The combination of M-PPE-M, TBS, and DVB gave a balance of high T_g, increased toughness, low dielectric properties, low moisture absorption, and low density.