PNVP-g-PVDF copolymers were synthesized and used to produce microfiltration membranes. The pore size and distribution varied with the grafting concentration and the density of graft points. A significant decrease of the amounts of adsorbed BSA indicated improved antifouling properties of PVDF. The MF membranes were further functionalized via surface-initiated block copolymerization with DMAEMA to obtain (PVDF-g-PNVP)-b-PDMAEMA MF membranes. Quaternization of the tertiary amine groups of the PDMAEMA brushes gave rise to a high concentration of quaternary ammonium salt on the membrane surfaces. The bactericidal effect of the QAS-functionalized membranes on E. coli was also demonstrated and discussed.

New acrylic rubber hollow fiber damping materials were successfully produced by dry–wet spinning technique. The effect of polymer concentration and blending ratio on ACM/PVC hollow fiber were investigated. The results showed that the tensile strength increased with the increase of polymer content and decreased with the decrease of blending ratio. DMA revealed that varying the size of inner diameter, the loss tangent (tan δ) would change. FTIR proved certain interactions among them. In addition, the position of peak of the glass transition temperature not only shifted to a higher temperature with the increase of PVC content, but also its temperature range of tan δ > 0.3 was 40–65°C, inferring that ACM/PVC mixture is a promising damping‐material. The outer skin and inner skin structure of ACM/PVC hollow fiber by SEM were different from that used in water treatment due to the differences between materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Waste rubber powder (WRP)/hindered phenol composites were successfully prepared by mixing tetrakis[methylene‐3‐(3‐5‐ditert‐butyl‐4‐hydroxy phenyl) propionyloxy] methane (AO‐60) into WRP for modification and recycling. The damping properties of the composites were systematically investigated through dynamic mechanical analysis. The experimental results indicate that the damping loss factor (tan δ) of WRP increases sharply from 0.366 to 0.734 via the modification process. With an increase in AO‐60, the tan δ value and the storage modulus in the glassy state gradually increase, and temperature dependence of loss peak gradually improves. The effects of the particle size of WRP, vulcanization temperature, vulcanization pressure, and vulcanization time on damping properties of the composite were investigated further. J. VINYL ADDIT. TECHNOL., 20:225–229, 2014. © 2014 Society of Plastics Engineers

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Optimization designs on the parameters of seven-layers of alternately laminated thin plate structures have been carried out through two orthogonal experiments and a dynamic mechanical analysis apparatus (DMA Q800), including the variations of damping material species, the fiber orientation angle in constrained layers and the thickness of the damping layer. The effects of these parameters on the loss factor of the structures have been investigated. It may provide some experimental basis for new anisotropic design system of the alternately laminated damped structures. Firstly, the experimental results show that the second and the sixth damping layers are respectively the best-influencing layers on the frequency range and the temperature range of the loss factor. As for the second damping layer, the greater the thickness, the better the frequency characteristics of internal friction. Secondly, the effects of the second outer constrained layer on the loss factor are the highest, and the structural damping characteristics are best when the orientation angle is close to 90. Finally, temperature and frequency characteristics of the loss factor can be optimized with different damped materials in different damping layers.