Study On The Properties Of Excellent Heat Resistant Resin Modified By Polyhedral Oligomeric Silsesquioxane (POSS)

In this paper, the octa(aminophenyl)silsesquioxane (OAPS) were synthesized. Furthermore, a novel polyimide (PI) hybrid nanocomposite containing polyhedral oligomeric silsesquioxane (POSS) with well defined architecture had been prepared by copolymerization of octa(aminophenyl)silsesquioxane (OAPS), 4,4'-oxydianilinediamine(ODA), and 4,4'-carbonyldiphthalic anhydride (BTDA). POSS as nano-particles was covalently attached to the polymer backbone successfully. The results showed that the mechanical properties and thermal stability of the PI/POSS composites were significantly improved. The glass transition temperature (Tg) and modulus at high temperature dramatically increased, owing to the significant increase of the cross-linking density and molecular reinforcing effects of POSS in the nanocomposite. Taking pyromellitic anhydride (PMDA) instead of BTDA, the thermal properties wasn't improved.Heptamertic cyclopentyl Trisilanol (T7) was synthesized and Cyanat Ester Resin was modified by T7 to get a series of CE/T7 organic-inorganic materials with different content of T7. As a result, T7 was copolymerized with cyanate ester monomer. The result showed that the existence of T7 resulted in increased flexibility and thermal stability of CE resin, while the dielectric properties of the modified CE varied little.