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Vinylidenefluoride (VDF) has been homopolymerized and copolymerized with perfluoro-n-propylvinylether (PPVE) using bis(perfluoro-2-n-propoxyethyl)diacyl peroxide (BPPP) as the initiator in CF2ClCFCl2. The polymers obtained were characterized with 19F NMR and 1H NMR spectroscopy, DSC and TGA. The 19F NMR spectra were used to determine the polymer microstructures and end groups. Both PVDF and poly(VDF–PPVE)...
The polymer surface relaxation in thin films has been a long debating issue. We report a new method on studying surface relaxation behaviors of polymer thin films on a solid substrate. This method involved utilizing a rubbed polyimide surface with a pretilting angle in a liquid crystalline cell. Due to the surface alignment, the liquid crystals were aligned along the rubbing direction. During heating...
Spherical micelles of a series of poly(styrene-block-(2,5-bis[4-methoxyphenyl]oxycarbonyl)styrene) (PS-b-PMPCS) rod-coil diblock copolymers in a selective solvent can organize into large mono-layered films with a well-ordered hexagonal packing of the spheres after solvent evaporation. Organized domains in the spherical micelle film were observed by transmission electron microscopy (TEM) and atomic...
A series of 2,2′-disubstituted-4,4′-dihydroxybiphenyl monomers was prepared from 3,4,5-tris(n-alkoxy)benzyl chlorides (n=5, 6, 8, 10, 12) and tetramethylammonium salt of 4,4′-dihydroxydiphenic acid, which was synthesized from two different 5-step routes. 2,2′-Bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid was synthesized via 5-step route. A series of aromatic polyesters containing multiple alkyl...
Two series of diamine monomers, i.e., 4-[3,4,5-tris(n-alkan-1-yloxy)benzyl]-3,5-diaminobenzoate and 2,2′-bis{4-[3,4,5-tris(n-alkan-1-yloxy)benzoate]}-4,4′-biphenyldiamines containing multiple alkyl side chains, were synthesized in which the length of the alkyl side chains was varied from 5 to 18 ethylene units. Polyetherimides (PEIs) were prepared from these two diamines and bis[4-(3,4-dicarboxyphenoxy)phenyl]propane...
5,15-Bis(4-aminophenyl)-10,20-diphenylporphyrin (trans-DATPP) was synthesized via the condensation of meso-(4-nitrophenyl)dipyrromethane and benzaldehyde. The further reaction with zinc acetylacetonate hydrate afforded zinc 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin (trans-ZnDATPP). A series of soluble polyimides based on trans-DATPP or trans-ZnDATPP, 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl...
A series of newly designed polyimides, composed of aromatic polyimide backbones and methylene side chains with terminal 4-cyanobiphenyl groups, were synthesized based on the polycondensation of 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) with 2,2′-bis{ω-[4-(4-cyanophenyl)phenyoxy-n-alkoxycarbonyl]}-4,4′-biphenyl diamine (nCBBP, where n is the number of methylene units in the side chains)...
Two new asymmetric odd-numbered main-chain liquid crystalline (LC) polyesters (BPE-Cn) were synthesized through the condensation polymerization of A–B type asymmetric α,ω-carboxylic acid–hydroxyl terminated monomers with odd-numbers of methylene units in the spacers (BPCA-Cn-PmOH, where n=7 and 9). The phase behaviors and structures of these odd-numbered BPE-Cn samples were characterized using the...
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