In order to improve the performance of traditional sodium alginate (SA) hydrogels cross-linked by Ca2+ ions to meet greater application demand, a strategy was designed to structure novel SA-based gels (named OP-PN gels) to achieve both stimulus responsiveness and improved mechanical strength. In this strategy, the SA chains are co-cross-linked by CaCl2 and cationic octa-ammonium polyhedral oligomeric silsesquioxane (Oa-POSS) particles as the first network, and an organically cross-linked poly(N-isopropyl acrylamide) (PNIPA) network is introduced into the gels as the second network. Several main results are obtained from the synthesis and characterization of the gels. For OP-PN gels, their properties depend on the content of both uniformly dispersed Oa-POSS and PNIPA network directly. The increased Oa-POSS and PNIPA network content significantly improves both the strength and resilience of gels. Relatively, the increased Oa-POSS is greatly beneficial to the modulus of gels, and the increased PNIPA network is more favorable to advancing the tensile deformation of gels. The gels with hydrophilic PNIPA network exhibit better swelling ability and remarkable temperature responsiveness, and their volume phase transition temperature can be adjusted by altering the content of Oa-POSS. The deswelling rate of gels increases gradually with the increase of POSS content due to the hydrophobic Si–O skeleton of POSS. Moreover, the enhanced drug loading and sustained release ability of the target drug bovine serum albumin displays great potential for this hybrid gel in the biomedical field.

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Investigation of the effect of the surface properties of dispersed particles on the shear thickening behavior of their corresponding suspensions.

Application of porous polymeric materials is severely limited by their ultralow thermal conductivities. Herein, by promoting the formation of thermal conduction pathways, we fabricated open-cellular structured polyethylene/hexagonal boron nitride hybrid thermal conductors via melt compounding plus salt leaching. The structural analyses indicate that the inclusion of hBN can enhance the open-cell level of resultant materials. X-ray diffractions confirm the high in-plane alignments of hBN in each sample. Consequently, the test results evidence the superior thermal conductivities of our samples, and the thermal conductivities of each sample are characterized as functions of hBN loadings. Ultimately, our advanced porous thermal conductor with a low hBN loading of 3.1 vol% exhibits a high specific thermal conductivity of 0.75 (W/mk)/(g/cm3), which is 82.9% higher than virgin PE and far higher than bulk PE/hBN composites. Our work also intends to reveal the architectural advantages of open-cellular, as compared with the close-one, in fabricating porous materials with highly interconnected fillers.