Resultat (
engelska) 3:
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a novel bisphenol - a aniline type polybenzoxazine (pba - (a) modified with dianhydride was successfully prepared by reacting bisphenol - a aniline based benzoxazine (ba - (a) a resin with 3,3 ', 4,4' - benzophenonetetracarboxylic dianhydride (btda) in 1 - methyl - 2 - (pyrrolidone is nmp) solvent. the miscible monomer mixture was easily transformed into transparent pba - a / btda copolymers village thermal cure. - fourier transform infrared spectroscopy reveals the formation of ester linkage which is a covalent interaction between hydroxyl group of the pba) and the carbonyl group in the dianhydride. the pba - a / btda copolymers show only one glass transition temperature (tg) with the value as high as 263 degrees celsius to ba a: btda = 1.5: 1 mol ratio. the value remarkably is higher than that of the unmodified pba (i.e., 160 degrees celsius. in addition, the resulting pba - a / btda copolymers display relatively high degradation temperature up to 364 oc and substantial enhancement in char yield with a value of up to 61% by weight. moreover, the flexibility of the pba - a / btda copolymer samples is also significantly enhanced compared to the unmodified pba). the obtained copolymer demonstrates high potential for those applications that require high thermal and mechanical properties with fire resistant characteristics.
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