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To solve the problem of poor waterproof and moisture resistance caused by the high open-cell ratio of polyacrylate foam, a special foam stabilizer (MMA-g-SI) for acrylate was synthesized with polyacrylate as the main chain and aminosiloxane as the side chain. MMA-g-SI has good foam stability in the process of acrylate foaming, and can significantly reduce the surface tension and further increase the closed-cell content. When the amount of MMA-g-SI was 1.0 wt%, the water absorption of foam decreased from 64.3% to 2.1%. The point impact energy absorption increased from 50% to 72%, and the surface impact energy absorption increased from 28% to 35%. Moreover, with the increase of density, the point impact energy absorption of the foam increased, while the surface impact energy absorption decreased. The special foam stabilizer has a good application prospect in the field of acrylate foaming. KEYWORDS energy absorption, foam stabilizer, polyacrylate, poor waterproof, surface tension, 1 | INTRODUCTION With the development of technology, electronic devices, such as mobile phones and computers, have become a part of people's life. However, the screens of these electronic devices [...]

The comb‐like polymers with crystalline aliphatic side chains are synthesized and then applied as the supporting material of phase change material. First, poly(styrene‐co‐acrylic acid)n‐graft‐octadecylamine (P(S‐AA)n‐C18, wherein "n" denoted AA feed ratio) is prepared. The crystalline behaviors of the comb‐like polymer with different grafting densities are investigated. Then the paraffin@P(S‐AA)n‐C18 is obtained by packing paraffin into P(S‐AA)n‐C18. Attributed to the cocrystallization with paraffin, a form‐stable phase change material (FSPCM) with high content of paraffin (≥90 wt% paraffin in FSPCMs without obvious leakage) and enhanced thermal property is obtained. The melting and freezing enthalpies of FSPCMs reach 124.4 and 126.3 J/g, respectively, which are higher than that of pure paraffin. And good thermal cycling stability and good thermal stability of FSPCMs are also exhibited. The result offers an avenue for developing the high‐efficient thermal energy storage materials. [ABSTRACT FROM AUTHOR]

A comb‐like polymer containing crystallized alkyl side chains and the intermolecular hydrogen bonds between the linking groups was fabricated by grafting long‐chain fatty amine onto poly(styrene‐co‐acrylic acid)n (P(S‐AA)n, wherein "n" denoted AA feed ratio). The chemical structures and crystallization behaviors of the comb‐like polymer P(S‐AA)n‐g(p) (wherein "p" denoted the number of side‐chain carbon atoms) were analyzed by Fourier transform infrared, gel permeation chromatography, X‐ray photoelectron spectroscopy, and X‐ray diffractometer, differential scanning calorimetry, atomic force microscopy, respectively. It was found that the lamellar morphology could be generated by controlling the grafting density and side chain length of P(S‐AA)n‐g(p). Moreover, it was identified that the hydrogen bonds between amide groups could enhance the crystallinity and then adjust the interlamellar spacing of lamellar phase. As a result, P(S‐AA)70‐g(18) with the highest degree of crystallinity and closely packed lamellar morphology showed a good gas‐barrier performance, and the nitrogen permeability reached 1.78 × 10−14 cm3·cm/cm2·s·Pa. Furthermore, the permeation switch of the obtained comb‐like polymer could reach 500 times traversing the melting point. [ABSTRACT FROM AUTHOR]

A polymer foam material with both the open‐cell porous structure and the polyethylenemine (PEI)‐grafted inner face was constructed for CO2 capture. The porous poly(tert‐butyl acrylate) foam was first prepared via a concentrated emulsion polymerization, and then the carboxyl groups were introduced on the interface of porous polymer after the hydrolysis reaction. Subsequently, the surface of the foam was grafted with PEI, and finally the PEI‐grafted porous polymer foam designed as a CO2 capture material was obtained. The structures of the foams were characterized by infrared spectroscopy, EDS, and SEM. The CO2 adsorption properties were measured by adsorption/desorption cycles. As a result, the polymer foam contained a large number of amine groups (13.9 wt % N), and therefore possessed a high CO2 adsorption capacity (5.91 mmol g−1 at 40°C and 100 kPa). In addition, they also exhibited high CO2 adsorption rate, good selectivity for CO2‐N2 separation, and good stability according to CO2 cyclic adsorption/desorption test. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47844. [ABSTRACT FROM AUTHOR]