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The synthesis and application of polybenzoxazine adsorption resin was studied. First, the precursor was synthesized by the solventless method. And then a kind of spherical and granular polybenzoxazine resin was obtained using reverse-phase suspension polymerization technique in the process of solidification. Besides, the influence of dispersion medium, the volume ratio of precursor to medium, the solidification temperature, and the agitation speed were studied in detail in the process of polymerization. Second, the spherical shape of the polybenzoxazine resin was identified by scanning electronic microscope and the thermal stability of resin was measured by thermogravimetric analysis. Finally, the adsorption capacity of the spherical resin on pyridine was studied in cyclohexane systems. The correlation coefficient of Langmuir adsorption constant temperature line was bigger than 0.99, which indicated that the equilibrium sorption date was coincident with the Langmuir isotherm equation. And the saturated adsorptive capacity of dried resin achieved 222.2 mg g−1. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

A novel preservative film was prepared by blending konjac glucomannan (KGM) and poly (diallydimethylammonium chloride) (PDADMAC) in aqueous system. The effects of PDADMAC content on the miscibility, morphology, thermal stability, and mechanical properties of the blend films were investigated by density determination, scanning electron microscopy (SEM), attenuated total reflection infrared spectroscopy (ATR-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile tests. The results of the density determination predicted that the blends of KGM and PDADMAC were miscible when the PDADMAC content was less than 70 wt %. Moreover, SEM and XRD confirmed the result. ATR-IR showed that strong intermolecular hydrogen bonds interaction occurred between the negative charge groups of KGM and the quaternary ammonium groups of PDADMAC in the blends. The tensile strength and the break elongation of the blends were improved largely to 106.5 MPa and 32.04%, when the PDADMAC content was 20 wt %. The thermal stability of the blends was higher than pure KGM. Results from the film-coating preservation experiments with lichi and grapes showed that the blend film had excellent water-holding and preservative ability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

In this study blend films of chitosan (CH) and hydroxypropyl guar gum (HGG) were prepared using a conventional solvent-casting technique and were dried at room temperature. Their miscibility and other properties were studied by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, scanning electron microscopy, differential thermal analysis, ultraviolet analysis, and tensile strength tests. The physical and thermal properties of the films depended on the blending ratio. The maximum tensile strength and breaking elongation values achieved were 58.94 MPa and 17.25%, respectively, with a 60% content of HGG. Thermal stability also was improved, and the blend film containing 60% HGG had greater thermal stability than did the other blend and pure CH films. In addition, the best optical transparence was observed from 500 to 800 nm in the blend film containing 60% HGG. The results indicate that intermolecular interactions that resulted from hydrogen bonding between CH and HGG occurred in the blend films. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1991–1995, 2003

Regenerated cellulose (RC) films were plasticized with glycerol, glycerin α-monobutyrate, glycerin α-monocaproate, glycerin α-monocaprylate, and glycerin α-monocaprate. The structure and properties of the films were investigated by using Fourier transform IR, wide-angle X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and tensile tests. The experimental results showed that the addition of plasticizer enhanced the elongation at break, thermal stability, and crystallinity and lowered the tensile strength of the films. The formation of hydrogen bonds between the cellulose and plasticizers weakened the inter- and intra-hydrogen bonds among cellulose molecules, leading to reduced tensile strength. These α-monoglycerides have relatively good plasticizing effects. Compared with glycerol, the resistance against water washing of the synthesized compounds was significantly enhanced. With the increase of the carbochain length of the α-monoglycerides, the plasticizing effect decreased but the resistance against water washing was enhanced. When the RC films were immersed in a 10% glycerin α-monocaproate solution, the elongation at break increased to 15% and stayed at 14.8% after water washing. Glycerin α-monocaproate might be better for plasticizing RC films than others. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3500–3505, 2003

In this article, two kinds of poly(phenylene sulfide) (PPS) with terminal groups predominated by chloro and thiohydroxy groups have been synthesized using endcapping by adding monomer. Compared with PPS with terminal thiohydroxy groups, PPS with terminal chloro groups possesses a greater crystallinity, larger crystallite dimensions, a larger particle size, higher thermal stability, and a longer gelation time. © 1993 John Wiley & Sons, Inc.

The visualization of monolayers at the air/water interface by Brewster Angle Microscope (BAM) was used to watch the movement of the domains of surfactant or surface-active complexes without any adscititious probe materials, and to examine the changes in surface rheology of partially hydrolyzed polyacrylamide (HPAM)/surfactant systems. Clear indications of rheological properties at the air/water interface are obtained over substantial concentration regions of the HPAM/Sodium Dodecyl Benzene Sulfonate (SDBS) and HPAM/Triton X-100/SDBS systems, respectively. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 704–706, 2000