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A novel blend membrane with temperature-and pH-responsive properties was prepared by the physical blending of poly(vinylidene fluoride) (PVDF) bulk material, poly(N-isopropylacrylamide) (PNIPAAm) microgels and poly(acrylic acid) (PAA) microgels with a simple and practical procedure, which is suitable for industrial scale production. The composition and structure of the blend membrane were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and fieldemission scanning electron microscope (FESEM). The results indicated that the incorporation of PAA and PNIPAAm microgels improved the pore size, porosity and hydrophilicity of the blended membrane, leading to a higher water flux and remarkable antifouling property. In particular, the blend membrane exhibited temperature-and pH-sensitive characteristics. The dual responsive feature makes it easy to control the blend membrane's rejection properties as well as the water flux and helps the membrane retain preferable mass transfer and separation property when responding to one of the investigated stimuli.

Palladium (Pd) nanoparticles with different sizes are in situ synthesized by reduction of PdCl2 with NaBH4 as reductant in the presence of poly(methacrylic acid) (PMAA)microspheres. The obtained PMAA/Pd composites are characterized by Fourier transform infrared spectra, X‐ray diffraction, and Transmission electron microscopy. The catalytic activity of the PMAA/Pd composites is investigated using a model reaction, that is, reduction of p‐nitrophenol to p‐aminophenol. The reaction shows first‐order kinetics, and the reaction rate increases with increasing reaction temperature, p‐nitrophenol concentration, and loadings of Pd nanoparticles on PMAA microspheres. The PMAA/Pd composites exhibit good stability, ascribing to the Pd nanoparticles stabilized by PMAA microspheres. POLYM. COMPOS., 35:2251–2260, 2014. © 2014 Society of Plastics Engineers