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The composite phase change material was prepared via the impregnation method using diatomaceous as the carrier and stearic acid as the phase change material. The effects of diatomite content, temperature, immersion time and pressure on the mass ratio of stearic acid and diatomaceous earth in the composite phase change materials were discussed. The experimental results showed that the optimum conditions for preparing stearic acid/diatomite composite phase change material were immersion temperature of 80℃, socking time of 2 h, diatomite mass fraction of 23.04%, and vacuum degree of 0.03 MPa. Finally, the infrared spectroscopy analysis of stearic acid/diatomite composite phase change energy storage material showed that there is no chemical reaction between stearic acid and diatomite. And they are held together by intermolecular forces.

A novel synthesis path for the monotelechelic polydimethylsiloxane with a diol-end group, abutyl-omega-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}polydimethylsiloxane, is described in this article. The preparation included three steps, which were anionic ring-opening polymerization, hydrosilylation, and epoxy addition. The structure and polydispersity index of the products were analyzed and confirmed by FTIR, 1 H NMR, 13 C NMR, HAH, and CAH.Correlated Spectroscopy and gel permeation chromatography. The results demonstrated that each step was successfully carried out and the targeted products were accessed in all cases.

In this study, α,ω-vinyl telechelic polyurethane macromonomers used as macromonomer and stabilizer of emulsion system were synthesized by reaction of poly(propylene glycol), 4,4-diphenylmethane diisocyanate (MDI), 2,2-dimethylolbutanoic acid (DMBA), diethylene glycol, and 2-hydroxyethyl acrylate (HEA). Different compositions of methyl methacrylate (MMA) and α,ω-vinyl telechelic polyurethane macromonomers were successfully carried out reversible addition-fragmentation chain transfer radical polymerization (RAFT) mediated by RAFT agent, 2-(dodecylthiocarbonothioylthio) propanoic acid. It was demonstrated that the waterborne polyurethane (WPU)-poly(methyl methacrylate) copolymer emulsions prepared by RAFT emulsion copolymerization exhibited enhanced storage stability. No precipitation was observed for longer than six months during the storage at ambient temperature for all the copolymer emulsions. With increase in addition amount of MMA, the electrolyte stability became worse. The water-resistance property and mechanical property of the WPU/poly(methyl methacrylate) copolymer films were improved obviously.