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The polycarbonate copolymers poly[trimethylene carbonate-co-2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate] [P(TMC-co-PTC)] were synthesized by the ring-opening polymerization of trimethylene carbonate (TMC) and 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) with tin(II) 2-ethylhexanoate and aluminum isopropoxide as the catalysts. These copolymers were further reduced by a palladium/carbonate (Pd/C; 10%) catalyst to produce partly deprotected copolymers. These two types of copolymers were characterized by 1H-NMR, Fourier transform infrared spectroscopy, UV spectroscopy, gel permeation chromatography, differential scanning calorimetry, and an automatic contact angle meter. The influences of the feed molar ratio of the monomers, the catalyst concentration, the reaction time, and the reaction temperature on the copolymerization process were also studied. The copolymerization of the TMC and PTC monomers was a nonideal copolymerization, and the copolymerization reactivity ratio of TMC was higher than that of PTC. In vitro degradation tests indicated that the partly deprotected copolymers possessed faster degradation rates and more hydrophilicity than the corresponding unreduced copolymers. Moreover, the degradation of these two type copolymers increased when the pH value of the buffer solutions decreased. In vitro drug-release experiments showed that these two types of copolymers had steady drug-release rates and good controlled release properties. Moreover, the partly deprotected copolymers had faster drug-release rates than the corresponding unreduced copolymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Polystyrene/carbon nanotubes composites were readily prepared by reversed microemulsion polymerization. Compared with the composites prepared by solution mixing, the uniform dispersion of carbon nanotubes in polymer matrix could be obtained more easily and the thermal and electrical properties of the as-prepared composites were also enhanced. The as-prepared composites were deposited onto a microelectrode array to fabricate a vapor sensor. The response for different organic vapors was evaluated by monitoring the change in the resistance of the composites upon exposure to various gases. The change in resistance was of the order of about 103 for the composites prepared by reversed microemulsion polymerization. The chemical sensors based on the composites prepared by reversed microemulsion polymerization presented excellent reproducibility and reversibility in response. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

A series of copolymers were synthesized by the ring-opening bulk polymerization of e-caprolactone (CL) and 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) with tin(II) 2-ethylhexanoate as a catalyst. These copolymers were further reduced with a palladium/carbonate catalyst to obtain partly deprotected copolymers. The two types of copolymers that were obtained were characterized with 1H-NMR, Fourier transform infrared spectroscopy, UV, gel permeation chromatography, differential scanning calorimetry, and automatic contact-angle measurements. The influences of the monomer feed molar ratio, catalyst concentration, and reaction time as well as the reaction temperature on the copolymerization process were also studied. The copolymerization of CL and PTC monomers was a nonideal copolymerization, and the copolymerization reactivity ratio of CL was higher than that of PTC in the polymerization process. In vitro degradation tests indicated that the partly deprotected copolymers possessed faster degradation rates and greater hydrophilicity than the unreduced copolymers. In vitro release profiles of fluorouracil from the copolymers showed that these two types of copolymers had steady drug-release rates and good controlled-release properties. Moreover, the partly deprotected copolymers had faster drug-release rates than the unreduced copolymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

A series of polycarbonate copolymers were synthesized by the ring-opening bulk polymerization of 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) and 5,5-dimethyl trimethylene carbonate (DTC) with tin(II) 2-ethylhexanoate and aluminum isopropoxide as initiators. The copolymers obtained were characterized by 1 H-NMR, Fourier transform infrared, and ultraviolet. The influence of the molar ratio of the monomers, the initiators, and their concentrations, the reaction time, and the reaction temperature on the copolymerization was also studied. The copolymerization of monomers DTC and PTC was a nonideal copolymerization, and the copolymerization reactivity ratio of the monomer DTC was higher than that of PTC in the copolymerization process. In vitro release profiles of fluorouracil from the copolymers showed that the copolymer had a steady drug-release rate and good controlled-release property.