Krystalická struktura a morfologie čerstvě připravených vzorků symetrických aromatických polyesterů II.poly(p-fenylen 2,6-naftalát)

Abstract

Polymerací v tenké vrstvě v tavenině (CTFMP) naftalen chloridu s hydrochinenem ( NC/ HQ;1/1) při polymerační teplotě (Tp) pod ca 300°C byly získány relativně tlusté protažené krystaly.

Confined thin film melt polymerization (CTFMP) of naphthalene chloride/hydroquinone (NC/HQ, 1/1, molar) mixtures at polymerization temperatures (T-p) below ca. 300degreesC resulted in relatively thick, elongated crystals. Polymerization of NC/HQ above 300degreesC between glass yielded well-formed lamellar crystals ca. 100 Angstrom thick. Phase I and II [001] ED patterns were obtained for all T-p the relative amount of phase I increasing with T-p. Polymerization of naphthalene dicarboxylic acid/hydroquinione diacetate 1/1 mixtures at high T-p also yielded lamellar crystals that "curled up" off of the substrate. When the high temperature CTFMP polymerization was conducted between mica, aggregates of lamellae on edge developed but epitaxial growth did not occur. Epitaxial growth of lamellae between mica could be obtained, however, by confined thin film solution polymerization, with both of the latter samples yielding apparently related ED patterns from a different unit cell than phase I or II. Fiber patterns, obtained from sheared samples, indicated considerably greater crystal disorder than in the nascent crystals. Refinement of the phase I unit cell parameters, based on the [001] and [0 (1) over bar1] ED patterns, with modeling based on Cerius(2), suggests a monoclinic phase I unit cell with a = 7.76, b = 5.71, c = 14.99 Angstrom, alpha = gamma = 90degrees, beta = 99.7degrees, rho = 1.47 g/cm(3), space group P12(1)/a1.