Polymer Journal
Vol. 37, No. 11 (November, 2005)

Web Release Date: November 15, 2005

797-812 Photorefractive Effect of Liquid Crystalline Materials  T. Sasaki [Full Text PDF(J-STAGE)]

This paper reviews our recent work on the photorefractive effect in liquid crystalline materials. The interference of two laser beams in a photorefractive material establishes a refractive index grating. This phenomenon enables the creation of different types of photonic applications. Recently, the development of organic photorefractive materials has been attracting great interest. Liquid crystalline materials are a strong candidate for practical photorefractive materials and application. In this paper, the photorefractivity of liquid crystalline polymers and ferroelectric liquid crystals is described.

[Regular Article] Web Release Date: November 15, 2005

813-817 Removal of Diazonaphthoquinone/Novolak Resist Using UV Laser (266 nm)  H. Horibe, T. Kamimura, T. Hata, M. Yamamoto, I. Yamato, O. Nigo, M. Fujita, A. Yoshikado, and K. Yoshida [Full Text PDF(J-STAGE)]

This study revealed a promising method for removing positive-tone diazonaphthoquinone/novolak resist. The fourth harmonic of an Nd3+:YAG pulsed laser was irradiated onto the resist. Resist was removed when laser power exceeded 35 mJ/cm2. XPS proved that 1100 nm-thick resist could be completely removed from a Si surface when it was irradiated almost 700 mJ/cm2. The resist onto three-inch Si wafer was removed in two minutes by laser. No damage to the processed Si wafer could be detected. This method is good for environment.

[Regular Article] Web Release Date: November 15, 2005

818-825 Synthesis and Magnetic Property of Poly[bis(4-methoxyphenyl)aminiumacetylene]s  H. Murata, D. Miyajima, R. Takada, and H. Nishide [Full Text PDF(J-STAGE)]

Poly[bis(4-methoxyphenyl)aminiumacetylene]s were designed and synthesized as a π-conjugated polymer bearing multiple aminium radicals. Bis(4-methoxyphenylaminoacetylene and 1-methyl-2-bis(4-methoxypheny)aminoacetylene were synthesized and polymerized with a metathesis catalyst to yield the corresponding polyacetylenes. The oxidation of the polymer with SbCl5 gave the corresponding poly(aminium radical)s as blue powders. The introduction of a methyl group onto the polyacetylene backbone significantly enhanced the chemical stability of the poly(aminium radical). We succeeded in spin alignment through the π-conjugation of the polyacetylene backbone with a spin quantum number of S = 4/2.

[Regular Article] Web Release Date: November 15, 2005

826-832 Physical Modification of Agar: Formation of Agar-fatty Acid Complexes  K. Prasad, K. Trivedi, R. Meena, and A. K. Siddhanta [Full Text PDF(J-STAGE)]

Four saturated (C12:0–C18:0) and one unsaturated fatty acid (C18:1) were allowed to react with agar and the resulting agar-fatty acid inclusion complexes were investigated. The bound fatty acids present in agar-fatty acid complexes were isolated and estimated by HPLC using UV–vis detector. Subsequently, confirmatory analysis of these fatty acids were done using TOF LC–MS technique. It was observed that the presence of fatty acids in the agar-fatty acid complexes affected the physical (e.g. gel strength, viscosity, swelling behaviour, syneresis and surface tension) and rheological behaviour (e.g. dynamic viscosity and viscoelasticity) of agar sol and gel.

[Regular Article] Web Release Date: November 15, 2005

833-840 Mechanism and Kinetics of Epoxy-Imidazole Cure Studied with Two Kinetic Methods  T. Zhou, M. Gu, Y. Jin, and J. Wang [Full Text PDF(J-STAGE)]

Curing kinetics and mechanism of the diglycidyl ether of bisphenol-A (DGEBA) initiated with 2-ethyl-4-methylimidazole (EMI-2,4) were studied with two methods by using differential scanning calorimetry (DSC). Method I and Method II were deduced by assuming a constant E and a variable E, respectively. With Method I, the cure reaction activation energy E, the frequency factor A and the overall order of reaction m + n are calculated to be 49.03 KJ mol−1, e14.5 and 1.22, respectively. With Method II, E is proved to decrease initially, and then increase as the cure reaction proceeds. The variations of E were used to study the cure reaction mechanism.

[Regular Article] Web Release Date: November 15, 2005

841-846 Amphiphilic Block Copolymers of Polyvinyl Alcohol and Polystyrene and Their Surface Properties  H. Li, Y. M. Zhang, M. Z. Xue, and Y. G. Liu [Full Text PDF(J-STAGE)]

Well-defined amphiphilic block copolymers of poly(vinyl alcohol)-b-polystyrene (PVA-b-PS) were successfully synthesized by atom transfer radical polymerization of styrene, followed by complete hydrolysis of polyvinyl acetate block. The block copolymers were characterized by GPC, FT-IR and 1H NMR. PVA-b-PS has amphiphilic properties, which was confirmed with the study on the surface activity in N,N'-dimethylformamide and toluene. And the Pearlescent pigment which was modified by PVA-b-PS shows improved dispersing stability.

[Regular Article] Web Release Date: November 15, 2005

847-853 Ring-Opening Polymerization of ε-Caprolactone Using Novel Dendritic Aluminum Alkoxide Initiators  T. Muraki, K. Fujita, A. Oishi, and Y. Taguchi [Full Text PDF(J-STAGE)]

We have prepared two novel types of dendritic aluminum alkoxide initiators —an aluminum trialkoxide dendrimer and a dithiothreitol-derived aluminum alkoxide dendrimer— for ring-opening polymerization of ε-caprolactone. The possitive dendritic effect on the relationship between the generation of the dendritic initiator and the polydispersity (Mw/Mn) of poly(ε-caprolactone) was observed by the use of the dithiothreitol-derived dendritic aluminum initiator.

[Regular Article] Web Release Date: November 15, 2005

854-857 Fabrication of Depth-controllable Nanochannel with Polymer Nanoassembled Films Using Atomic Force Microscopy Lithography  T. Mikayama, T. Suzuki, J. Matsui, and T. Miyashita [Full Text PDF(J-STAGE)]

Fabrication of a nanochannel consisting of poly(N-neopentylmethacrylamide) Langmuir–Blodgett film (polymer nanosheet) utilizing atomic force microscopy (AFM) lithography is demonstrated. We obtained the nanochannel with 1–20 nm depth and 150–280 nm width. The channel surface is highly homogenous which is an advantage for covering the channel tightly without leaking point. The depth of the channel increases linearly with increasing number of layers, which indicates that the channel depth is controllable in a nanometer level. The width of the nanochannel is independent with the thickness of the film.

[Note] Web Release Date: November 15, 2005

858-861 Novel Bimorph-Structured Hydrogel Containing Segregated Polymer Surfactant  H. Yan and K. Tsujii [Full Text PDF(J-STAGE)]

Bimorph-structured NIPA/NIPA–PMDP gel was fabricated from a NIPA gel containing a polymer surfactant (PMDP) by an electrophoretic method.

Web Release Date: November 15, 2005

862-865 Effect of 6-Dioctylamino-1,3,5-triazine-2,4-dithiol Concentration on the Polymer Plating on Iron Plates  K. Mori, Z.X. Kang, and Y. Oishi [Full Text PDF(J-STAGE)]

The polymer plating of 6-dioctylamino-1,3,5-triazine-2,4-dithiol(DO) in 0.1 mol/dm3–Na2CO3 aqueous solution, provided amorphous polymer film with a low density, when is conducted according to parabolic law in low DO concentrations such as 0.1 and 0.3 mmol/dm3. The rate-determining step was found to be on the diffusion of DO anions. When the polymer plating is carried out in high DO concentration such as 1, 5 and 10 mmol/dm3, polymer film increased with high rate in proportion to plating time according to linear law, indicating the charge transfer emitting electrons from DO anions to anode and had high crystalline, indicating a 26.7 nm of layer spacing distance

Web Release Date: November 15, 2005

866-869 Effects of Clay and LNR on Mechanical Properties and Morphology of NR/HDPE-Aramid Composites  I. Ahmad, N. A. Latif, and I. Abdullah [Full Text PDF(J-STAGE)]

Twaron fiber was hybridized with clay in order to study the effect of clay content in the composites on the mechanical and morphological properties. The results have shown that the mechanical properties improved significantly at low clay contents especially with the introducing of liquid natural rubber (Figure 1). However, at higher filler loading, the mechanical properties decreased. This indicates that clay in NR/HDPE/Twaron composites produce a good filler particle distribution and better particle wettability.