Abstract
| - Matrix polymerization can be viewed as an intriguing procedure for the preparation ofhomogeneous blends that are otherwise difficult or practically impossible to prepare. Poly(p-phenyleneterephthalamide) has been synthesized by direct polycondensation in the presence of poly(N-vinylpyrrolidone) or poly(4-vinylpyridine) as polymer matrices. The molecular weight effect of the latter polymerson the intrinsic viscosity of the aramid has been investigated. Poly(p-phenyleneterephthalamide),characterized by intrinsic viscosity as high as 14.2 dL/g, is obtained when high molecular weight poly(N-vinylpyrrolidone) is used. The intimate composites formed in situ have been characterized by solid-state NMR. The parent and daughter polymers in the composite present the same proton T1 relaxationtimes in the rotating frame, and this value differs from that of the neat polymers; this result demonstratesthe intimacy of the blend at the level of a few nanometers.
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