Volume 44 Issue 10, October 2012

A retardation film consists of optical polymer to control polarized light by the oriented birefringence. One of the issues of the films is wide-banding of birefringence. We have researched a novel molecular design to control dispersion, and found that the wide-band properties appear in a narrow range near the birefringence zero point, which is determined by the volume fractions of the positive monomer units to the negative units. The wide-band retardation film has been industrialized using a novel co-PC with a fluorene ring based on the molecular design.

Segmented polyurethane prepared using a novel chain extender, calcium lactate along with polytetramethylene glycol and hexamethylene diisocyanate. The properties of the synthesized polyurethane compared with that of polyurethane without any calcium. The prepared polymer has high glass transition temperature and storage modulus, and has improved mechanical properties. In vitro hemocompatibility evaluation reveals that the material is blood compatible and does not induce any hemolysis to blood.

Chemiluminescence spectra of natural rubber, chloroprene rubber and ethylene propylene diene rubber were measured in N₂ and in air with a multichannel Fourier-transform chemiluminescence spectrometer. Samples were measured before and after γ-ray irradiation in air and in the absence of O₂. A strong emission from ethylene propylene diene rubber was observed in air only when the sample was γ-irradiated in air. The observed spectrum was separated into two bands at 678 and 523 nm because of peroxidic compounds and excited carbonyl groups, respectively.

Analysis of photoproducts derived from 1-(arylmethyloxy) anthracene initiator 1 as well as polymer end groups demonstrated that the arylmethyloxyl radical and arylmethyl carbocation are involved in the initiation steps of St and CHO polymerization reactions, respectively. The ability of the radical and carbocation species to initiate polymerizations increased with the stability of these species.

The structural development during the CO₂ laser-heated drawing of low-oriented α-crystalline as-spun PBT fibers was analyzed with a time resolution of 0.3 ms. The α-crystal was transformed into an oriented β-form crystal at the necking position, and the crystallite size and orientation were increased <2 ms after necking at the temperature of 100–160 °C. In contrast to the PET and PEN, quasi-smectic structure was not observed before crystallization. The oriented β-crystal of the drawn fiber transformed into the oriented α-crystal when the drawing tension was released.

The surface of polyimide (PI) film was successfully patterned by nanoimprinting poly(amic acid) (PAA) film and then hard baking. An appropriate nanoimprinting process was established through the study of the thermal and dynamic mechanical properties of PAA and PI film. Atomic force microscopy revealed that line pattern was transferred from silicon mold to PI film successfully and the nanostructures remain undamaged even though a larger shrinkage took place during the hard baking.

Three series of functionalized poly(aryl ether ketone)s/metallophthalocyanine nanocomposites are prepared using the solution cast method. They exhibit well dispersion and better dielectric properties.

UV–vis spectra of (a) poly(N-methyl pyrrole) (PNMPy), (b) P(CPDT-co-NMPy) and (c) PCPDT deposited onto indium-tin-oxide-coated at the neutral state. Insets: (A) light yellowish green, (B) reddish brown, (C) purple are de-doped films, and (A′) pale cyan, (B′) light blue, (C′) blue are doped films of PNMPy, P(CPDT-co-NMPy) and PCPDT, respectively. The different electrochromic properties of the three polymers confirmed the occurrence of copolymerization between NMPy with CPDT

The graphene oxide (GO)-reinforced poly(vinyl alcohol) (PVA) nanocomposites were prepared using a simple and environment friendly process using aqueous medium. GO was revealed to be nanodispersed in the PVA matrix. The Young’s modulus of the nanocomposites largely exceeded the predicted value with only a low content of GO. We also revealed the increase in the thermal resistance and the barrier properties. As a result, not only the excellent properties but also the advantageous effects derived from the sheet-like structure of GO were successfully imparted to the nanocomposites.

An inorganic metal salt, copper sulfate (CuSO₄), was mechanically mixed with acrylate rubber (AR) and heat pressed to prepare a novel crosslinkable AR/CuSO₄ composite. The coordination reaction between the ester lateral groups and the copper (II) ions was carried out at elevated temperatures. A straightforward method of vulcanizing AR was explored via the introduction of in situ coordination crosslinking.