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Thermal expansion molding process (TEMP) is a new technology for integrated molding sandwich composites. However, the development of high‐performance expandable foam prepreg limits the scale applications of this technology. In this study, epoxy foam prepreg (M‐1) with expandable function was used to prepare foams with different expansion ratios via restricted foaming. Three suitable expansion ratios were determined to prepare foam sandwich composites by analyzing the density, bubble sizes, compressive strength, and expansion pressures of expandable foam. The maximum expansion pressure produced by four, six, and eight times of foam expansion were 251, 160, and 115 kPa, respectively. Tensile test and digital imaging computer technology confirmed that with the increase of foam expansion ratio, the strength decreased, but the plastic deformation ability increased. Failure modes such as foam matrix fracture, glass fiber mat fracture, and mutual‐slipping between the foam matrix and glass fiber mat occur during the stretching process. Finally, the PMI/M‐1 foam hybrid sandwich composites with three structures were prepared via the TEMP technology, which verified the feasibility of this technology in forming sandwich composites. [ABSTRACT FROM AUTHOR]

Poly vinyl acetate grafted calcium alginate hydrogel microspheres were prepared with bovine serum albumin (BSA) as molecular template. The microspheres exhibited homogeneous and core-shell structure according to different preparation strategy. The rebinding and swelling property of microspheres showed responsiveness toward ionic strength, temperature, and pH. It was found the highest separation factor of 1.85 and imprinting efficiency of 1.75 when the Ca2+ ionic strength was 1.25 and 0.34 mol/kg, respectively. The separation factor was found decreased as temperature grew from 29 to 45°C while the imprinting efficiency reached a peak value at about 37°C. Separation factor of BSA imprinted microspheres at different pH was also recorded and two peaks were found, which were considered to be caused by the similar swollen state due to ionic and covalent crosslinking structure of modified microspheres. The recognition responsiveness is suggested to be influenced by environmental effects due to the changing in imprints' configuration at different swollen states. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]