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Modulated-temperature differential scanning calorimetric and dynamic mechanical analyses and dielectric spectroscopy were used to investigate the glass transition of hydrated wheat gliadin powders with moisture absorption ranged from 2.30 db% to 18.21 db%. Glass transition temperature ( T) of dry wheat gliadin was estimated according to the Gordon-Taylor equation. Structural heterogeneity at high degrees of hydration was revealed in dielectric temperature and frequency spectra. The activation energies ( E) of the two relaxations were calculated from Arrhenius equation. [ABSTRACT FROM AUTHOR]

Environment friendly thermosetting composites were prepared by blending wheat gluten (WG) and rice protein (RP) at different weight ratios with glycerol as plasticizer followed by compression molding the mixture at 120°C to crosslink the proteins. Reducing agent of sodium bisulfate and sodium sulfite and crosslinking agent formaldehyde were used to adjust the properties of the composites. Morphology, moisture absorption and tensile properties were evaluated. The results showed that formaldehyde could increase tensile strength of the composites without significant influence on Young's modulus and elongation at break. On the other hand, reducing agents could improve tensile strength and extensibility simultaneously, which was much marked at WG/RP ratios from 7/3 to 3/7. [ABSTRACT FROM AUTHOR]

The dynamic rheological properties of a composite composed of solution-polymerized styrene butadiene rubber (SSBR) filled with starch/silica (SiO2) compound fillers were studied by means of temperature, frequency and strain sweeps, respectively, and the influence of the starch content in the compound fillers (SCCF) on the rheological behaviors was discussed. It is found from frequency sweeps that a maximum of loss tangent (tanδ) appears at 20 rad/s, which is independent of SCCF. G′ of the composites decreases whereas tanδ and critical strain (γc) of Payne effect increase with increasing SCCF. The reasons for these are believed to be that both SiO2 and starch could form filler networks due to interaction of hydrogen bounding between them, and the interactions between SiO2 and SSBR are stronger than those between starch and SSBR. Moreover, increasing SCCF in the compound fillers is in favor of improving the stability of the filler networks. Furthermore, tanδ values at 0°C and 60°C representing the properties for the wet traction and the rolling resistance of SSBR composites respectively can be improved by partial replacing SiO2 with starch. However, the reinforcement effect of starch to SSBR is weaker than that of SiO2 due to starch agglomeration. [ABSTRACT FROM AUTHOR]

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene (LDPE), ethylene copolymer and organoclay. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer. [ABSTRACT FROM AUTHOR]

Examines the nonlinear J-E characteristics of conductive composites based on high density polyethylene under self-heating equilibrium. Determination of filler contents and ambient temperature; Involvement of the conduction behavior in the limited microstructure transformations; Development of the reversible thermal fuse model.