Homoepitaxial Crystallization in Films of a Thermotropic Liquid Crystalline Chloro-Poly(aryl ether ketone)

Abstract

The homoepitaxial crystallization in the films of a thermotropic liquid crystalline chloro‐poly(aryl ether ketone) is studied by transmission electron microscopy (TEM) and electron diffraction (ED). The homoepitaxy takes place in the temperature range 330–320°C, in which a highly ordered smectic crystalline phase of the copolymer with a single‐crystal‐like banded structure is formed during the cooling process from the isotropic melt. The homoepitaxial crystallizations with angles of 32° and 122° between the two b axes are the major populations observed, and possess epitaxial contact planes of (100)I–(210)II and (010)I–(210)II, respectively.

Poly[2,6‐(1,4‐phenylene)‐benzobisimidazole] Nanofiber Networks

“…It might be speculated that the brushlike crystals were formed by the homoepitaxial crystallization in the crystallization of poly(aryl ether ketone), polyimides and others as previously reported. [16][17][18][19][20] Low molecular weight oligomers form the plate-like crystals at the initial stage in the polymerization, and then higher molecular weight oligomers crystallize to form the needlelike crystals epitaxially on the plate-plane of the plate-like crystals with polymerization time. Alternatively, cilia formed on the surface of the plate-like crystals by the distribution of the molecular length of the precipitated oligomers might afford the crystal growth step to form the needle-like crystals reported in the crystallization of poly( p-phenylene benzobisthiazole).…”

Synthesis and Thermotropic Liquid Crystalline Behavior of Novel Main-Chain Poly(aryl ether ketones) Copolymer Containing Phthalazinone Moiety and Biphenyl Mesogen

“…24 Moreover, the fact that the heat fusion of melting (ÁH m ¼ 35:5 J g À1 ) was higher than that of isotropization (ÁH i ¼ 1:5 J g À1 ) also indicated that no highly ordered mesophase was shaped for P-5050. 20 The weight loss temperatures (T d ) of P-5050 was 510 C (T d5% weight loss percent) (from TGA curve), and the char yield (C y ) of P-5050 at 800 C in nitrogen was 63 wt. %.…”

“…[17][18][19][20][21][22] Quite recently, a novel kind of lyotropic liquid crystalline poly(aryl ether ketones) copolymer and several kinds of polyamides containging phthalazione structure which possessed nematic lyotropic liquid crystalline properties were firstly described in our works. [9][10][11]13 In the present paper, a novel kind of nematic thermotropic liquid crysatlline poly(aryl ether ketones) copolymer was prepared by a one-step mild solution polycondensation reaction with 4-(4-hydroxyl-phenyl)(2H)-phthalazin-1-one (DHPZ), 4, 4 0 -biphenol (BP) and 1, 4-bis(4-fluorobenzoyl)-benzene (BFBB).…”

Rhythmic growth of ring‐banded spherulites in blends of liquid crystalline methoxy‐poly(aryl ether ketone) and poly(aryl ether ether ketone)

“…To obtain different properties of poly(aryl ether ketone) for various applications, structural changes, such as introduction of lateral groups and mesogenic biphenyl units into the main chains, have been attempted 6, 7. Recently, we have been actively pursuing investigations on a series of thermotropic liquid crystalline poly(aryl ether ketone)s (LC‐PAEKs),8–10 which were obtained by introducing substituted side‐groups (such as chloro, p ‐phenyl, t ‐butyl, methoxy, 3‐trifluoromethylbenzene etc.) and biphenyl mesogenic units into the PAEK backbones.…”