Various polyblends of poly(vinyl chloride) and polyurethane (PU) dissolved in a mixture of tetrahydrofuran and N,N‐dimethylformamide were produced by electrospinning, in different ratios, with several electrospinning conditions, and the relationship between morphology and mechanical behavior of the resulting fiber mats was examined in detail. The surface tension, viscosity, and electrical conductivity of polymer solutions affecting electrospinning were measured, and scanning electron microscopy (SEM) along with a universal testing machine were used to examine the family of polyblends under investigation. The SEM images demonstrated that point‐bonded structures in the fiber mats rose with increasing PU composition, and the mechanical properties of the fiber mats, as determined in a static tensile test, can be considered to have a strong effect by the point‐bonded structure. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1256–1262, 2003

Maleated polyethylene (PEMA)/silicate nanocomposites with a different aspect ratio of silicate and maleated PEMA/SiO2 composite were prepared by melt intercalation. The nanocomposites with a high aspect ratio silicate (montmorillonite) showed a faster decrease in the terminal slope of the storage modulus and a steeper increase in complex viscosity than those with a low aspect ratio silicate (laponite) and SiO2. The addition of montmorillonite increases the crystallization and the melting temperature of PEMA but decreases above 3 vol % of the silicate content because of the increased viscosity. The nanocomposite with montmorillonite showed the highest yield strength and secant modulus among the composites because of the highest aspect ratio of the filler. It also revealed strong interfacial adhesion with the matrix and orientation during tensile deformation. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1454–1463, 2002

An ultra high molecular weight polyethylene was irradiated with the electron beam at dose levels ranging from 100 kGY to 1 MGy. The microstructures of the irradiated samples were characterized by FTIR, gel fraction measurement, DSC, and small‐ and wide‐angle X‐ray scattering. For the mechanical properties, a static tensile test and creep experiment were also performed. The crosslinking and the crystal morphology changes were the main microstructural changes to influence the mechanical properties. It was found that 250 kGy appeared to be the optimal dose level to induce crosslinks in the amorphous area and recrystalliztion in the crystal lamellae. At doses above 250 kGy, the electron beam penetrates into the crystal domains, resulting in crosslinks in the crystal domains and reduction in the crystal size and crystallinity. The static mechanical properties (modulus, strength) and the creep resistance were enhanced by the electron beam irradiation. The stiffness rather correlated with the degree of crosslinks while the strength with the crystal morphology. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3019–3029, 2005

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