Effect of Silane Coupling Agent and Compatibilizer on Properties of Short Rossells Fiber/Poly(propylene) Composites

Rossells fiber reinforced polypropylene composites were prepared by melt mixing. The fiber content was 20 wt%. Octadecyltrimethoxysilane (OTMS) and maleic anhydride grafted polypropylene (MAPP) were used to improve the adhesion between poly(propylene) (PP) and the fiber. The mechanical, rheological, and morphological properties, and heat distortion temperature (HDT) of the composites were investigated. Tensile strength, impact strength, flexural strength and HDT of MAPP modified PP composites increased with an increase in MAPP content. However, no remarkable effect of MAPP content on the Young's modulus of the composites was found. OTMS resulted in small decreases of tensile strength and Young's modulus, and increase in impact strength. Scanning electron micrographs revealed that MAPP enhanced surface adhesion between the fiber surface and PP matrix.     

Preparation and photoinduced isomerization study of a homopolymer and a copolymer based on 4′‐(6‐acryloxy)hexyloxy‐4‐methoxyazobenzene and acrylic acid

The synthesis and characterization of a copolymer based on 4′‐(6‐acryloxy)hexyloxy‐4‐methoxyazobenzene (MAB6) and acrylic acid (AA) are reported. A reaction was carried out by free‐radical polymerization, yielding an MAB6 homopolymer and an AA–MAB6 copolymer with an MAB6 concentration of 16–80%. A nematic phase was observed in the copolymer when the MAB6 content was 44% or higher. Both nematic and smectic phases were observed in the MAB6 homopolymer. All of the polymers were investigated for trans–cis–trans isomerization in a solid film. The samples were irradiated with nonpolarized ultraviolet light (385 nm) before absorption measurements were taken with an ultraviolet–visible spectrometer. The copolymer and homopolymer exhibited a thermal cis–trans isomerization, which could be described by a double‐exponential relaxation process (fast and slow). The relaxation experiment suggested that the hydrogen bonding may have hindered the slow process but had no effect on the fast process. A film of a copolymer sample with a high MAB6 content could be optically aligned by the exposure of the sample to polarized light (385 nm). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 4017–4024, 2003     

A polymer surface for antibody detection by using surface plasmon resonance via immobilized antigen

A polymer substrate based surface plasmon resonance (SPR) technique was developed for detection of specific monoclonal antibody 10B2 (MAb 10B2) against bacterium Acidovorax avenae subsp. citrulli (Aac). The monolayer of Aac antigen was physically immobilized on 95:5 polystryrene – copoly acrylic acid (95PSMA) for detection of antibody. The amount of antigen–antibody binding was found to depend on the surface density of immobilized Aac on the sensor surface and the antibody concentration. The detection limit was 5 μg/ml which was lower than the required concentration during the normal production of the antibody at 10–100 μg/ml. This suggests a possible use of surface for the antibody screening. Moreover, an application in antibody screening was explored by combination of surface plasmon resonance imaging (SPR imaging) and antibody detection assay on the 95PSMA surface. Two antigens of bovine serum albumin (BSA) and Aac were used as a model system for antibody screening. The result shows that both antibodies can be distinguished using the immobilized antigens on the 95PSMA surface based SPR imaging technique.