James H. Wang
Case Western Reserve University
Polymer Bulletin | 1990
Virgil Percec; James H. Wang
Summaryα,ω-Bis(2,6-dimethylphenol)-poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-2OH) was synthesized by the radical-cation phase transfer catalyzed polymerization of 4-bromo-2,6-dimethylphenol (1) in the presence of 2,2-di(4-hydroxy-3,5-dimethylphenyl)propane (2). Copolymerization experiments were performed by a liquid-liquid two phase, benzene/1.5 N NaOH (aq), phase transfer catalyzed reaction with tetrabutylammonium hydrogen sulfate (TBAH) or tricaprylmethyllammonium chloride (Aliquat 336) catalysts. A series of copolymerization experiments were performed with 1/2 molar ratios of 4/1, resulting in PPO-2OH with Mn in the range of 2200–3200 g/mol. Phase transfer catalyzed etherification of the PPO-2OH chain ends with p-chloromethylstyrene was used to synthesize α,ω-bis(vinylbenzyl ether)s of the PPO-2OH (PPO-2VBE). The chain microstructure and the fuctionality of both PPO-2OH and PPO-2VBE was studied by 200 MHz 1H-NMR spectroscopy.
Polymer Bulletin | 1990
Virgil Percec; Ulrich Epple; James H. Wang; Hans Adam Schneider
SummaryThe influence of the total monomer concentration on the radical reactivity ratio r1 of butyl methacrylate (BMA) (M1)-ω-(p-vinylbenzyl ether) macromonomer of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-VBE) (M2) monomer pair was investigated. For two different molecular weights of the PPO-VBE macromonomer (
Polymer Bulletin | 1991
James H. Wang; Virgil Percec
Polymer Bulletin | 1990
Virgil Percec; James H. Wang
\bar M_n = 14,000
Polymer Bulletin | 1990
Virgil Percec; James H. Wang
Polymer Bulletin | 1992
Virgil Percec; James H. Wang; Lisha Yu
,
Polymer Bulletin | 1991
James H. Wang; Virgil Percec
Journal of Materials Chemistry | 1991
Virgil Percec; James H. Wang
{{\bar M_w } \mathord{\left/ {\vphantom {{\bar M_w } {\bar M_n }}} \right. \kern-\nulldelimiterspace} {\bar M_n }} = 1.25
Journal of Macromolecular Science, Part A | 1991
Virgil Percec; James H. Wang
Polymer Bulletin | 1991
Virgil Percec; James H. Wang
and