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.

Morphology and mechanical properties of poly(ethylene terephthalate)-poly(hydroxybenzoic acid) and polycarbonate blends.

Abstract: Blends of an engineering plastic; polycarbonate (PC) and a liquid crystalline polymer; random copolymers of the poly(ethylene terephthalate) and the poly(hydroxybenzoic acid) were prepared in an internal mixer. Fibers were extruded from the capillary rheometer and spin-drawn at varying draw ratios. The morphology and the mechanical properties were investigated by DSC, SEM, polarizing optical microscopy, X-ray diffraction, and tensile tests. SEM studies revealed that the liquid crystalline polymer (LCP) formed finely dispersed spherical domains with a diameter of 0.2—2.0 micron in the PC matrix and the inclusions were deformed from the spherical droplets to fibrils as the draw ratio increased. The interphase adhesion between the two polymers was good and therefore it was confirmed that the LCP could act as a reinforcement of PC.

Flame-retardant polycarbonate resin composition

Abstract: A resin composition which is excellent in appearance, impact strength, hydrolysis resistance and drip prevention properties The resin composition comprises (A) 100 parts by weight of an aromatic polycarbonate resin (component A), (B) 001 to 6 parts by weight of a polymer mixture (component B) obtained by suspension polymerizing a styrene monomer, a maleic anhydride monomer and an acrylic monomer in the presence of polytetrafluoroethylene particles, and (C) 001 to 30 parts by weight of a flame retardant (component C)

Effect of drawing on structure and properties of a liquid crystalline polymer and polycarbonate in - situ composite

Abstract: Fibers (strands) with various draw ratios were spun from the liquid crystalline state of a pure aromatic liquid crystalline copoly(ester amide) and the melts of its blend with polycarbonate. Scanning electron microscopy (SEMI, wide angle X-ray scattering (WAXS), and differential scanning calorimetry (DSC) were employed to investigate the structure and properties of the resulting fibers. Mechanical properties of the fibers were also evaluated. It was found that both the crystallite size and heat of fusion of the liquid crystalline polymer (LCP) increase steadily with draw ratio. However, the crystal-nematic transition temperature of the LCP is virtually unaffected by drawing. Moreover, heat of fusion of LCP is much smaller than that of isotropic condensation polymers despite the presence of very sharp dmraction peaks in WAXS measurements. These results are ascribed to the (semi)rigid rod nature of the LCP chains and the persistence of an ordered structure in the LCP melt, i.e., entropy effect. It was further observed that tensile modulus and tensile strength along fiber axis rise with draw ratio for the composite fibers. The elastic modulus of the composite fibers were found to be as high as 19 GPa and tensile strength reached 146 MPa with draw ratios below 40 and an LCP content of 30 wt%. Compared with the thermoplastic matrix, the elastic modulus and tensile strength of the in-situ composite have increased by 7.3 times and 1.4 times, respectively, with the addition of only 30 wt% LCP. This improvement in mechanical properties is attributed to fibrillation of the LCP phase in the blend and the increasing orientation of the LCP chains along the fiber axis during drawing.

Controlled nanostructure and high loading of single-walled carbon nanotubes reinforced polycarbonate composite

Abstract: This paper presents an effective technique to fabricate thermoplastic nanocomposites with high loading of well-dispersed single-walled carbon nanotubes (SWNTs). SWNT membranes were made from a multi-step dispersion and filtration method, and then impregnated with polycarbonate solution to make thermoplastic nanocomposites. High loading of nanotubes was achieved by controlling the viscosity of polycarbonate solution. SEM and AFM characterization results revealed the controlled nanostructure in the resultant nanocomposites. Dynamic mechanical property tests indicated that the storage modulus of the resulting nanocomposites at 20 wt% nanotubes loading was improved by a factor of 3.4 compared with neat polycarbonate material. These results suggest the developed approach is an effective way to fabricate thermoplastic nanocomposites with good dispersion and high SWNT loading.