Polycarbonate

About: Polycarbonate is a research topic. Over the lifetime, 14032 publications have been published within this topic receiving 141740 citations. The topic is also known as: PC & Polycarbonate, PC.

Carbohydrate-Based Polycarbonates. Synthesis, Structure, and Biodegradation Studies

Abstract: Linear homo- and co-polycarbonates have been prepared from the sugar-based diols 2,3,4-tri-O-methyl-l-arabinitol and 2,3,4-tri-O-methylxylitol. Statistical co-polycarbonates were obtained from molar feed ratios of sugar:bisphenol A of 1:1 and 2:1. The polycarbonates were stable up to ∼280 °C with maximum decomposition rate above 345 °C. The arabinitol-based homopolymer was found to be semicrystalline whereas the xylitol-based one was amorphous. All the copolymers were amorphous with Tg ranging between 60 and 80 °C. Both homo- and co-polycarbonates showed high resistance to chemical hydrolysis; however, they were enzymatically degraded in different degree. The xylitol-based polycarbonates were the more easily degraded by lipase B from Candida antarctica in acetonitrile at 70 °Cthis enzyme showing a high selectivity toward the configuration of the sugar-based moiety.

Thermoplastic resin composition

Abstract: PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition which is excellent in physical property balance and has its flow property improved without deteriorating excellent properties inherent in an engineering plastic SOLUTION: The thermoplastic resin composition is obtained by adding 1-100 ptsmass copolymer (B) to 100 ptsmass engineering plastic resin (A) The copolymer (B) has a number average molecular weight of 3,000-40,000 and comprises a block or graft structure composed of 1-40 wt% polymer block (B1) which is incompatible with a polycarbonate resin and 60-99 mass% polymer block (B2) which is compatible with or has an affinity for the polycarbonate resin (provided that the total amount of B1 and B2 is 100 mass%) COPYRIGHT: (C)2004,JPO&NCIPI

Synthesis and Characterization of Novel Glycerol-Derived Polycarbonates with Pendant Hydroxyl Groups

Abstract: A novel type of glycerol-derived, water-soluble polycarbonate with pendant, primary hydroxyl groups was prepared from 2-(2-benzyloxyethoxy)trimethylene carbonate (BETC). Ring-opening polymerization of BETC and 2,2-dimethyltrimethylene carbonate (DTC) gave narrow distribution of homopolymers or random copolyiners with high molecular weights. The protecting benzyl groups were removed by catalyzed hydrogenation at atmosphere H 2 pressure to give hydroxyl polycarbonates without observable changes on the polymer backbone and molecular weight distribution. The hydrophilicity of the copolymers increases with tile increase in the hydrophilic glycerol-derived carbonate content.

Characterization of Thermo-Mechanical and Fracture Behaviors of Thermoplastic Polymers

Abstract: In this paper the effects of the strain rate on the inelastic behavior and the self-heating under load conditions are presented for polymeric materials, such as polymethyl methacrylate (PMMA), polycarbonate (PC), and polyamide (PA66). By a torsion test, it was established that the shear yield stress behavior of PMMA, PC, and PA66 is well-described by the Ree-Eyring theory in the range of the considered strain rates. During the investigation, the surface temperature was monitored using an infrared camera. The heat release appeared at the early stage of the deformation and increased with the strain and strain rate. This suggested that the external work of deformation was dissipated into heat so the torsion tests could not be considered isothermal. Eventually, the effect of the strain rate on the failure modes was analyzed by scanning electron microscopy.