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131.
Wei Zhou Jiawei Fang Shuwei Tang Zhengguo Wu Xiaoying Wang 《Molecules (Basel, Switzerland)》2021,26(12)
Cushioning and antibacterial packaging are the requirements of the storage and transportation of fruits and vegetables, which are essential for reducing the irreversible quality loss during the process. Herein, the composite of carboxymethyl nanocellulose, glycerin, and acrylamide derivatives acted as the shell and chitosan/AgNPs were immobilized in the core by using coaxial 3D-printing technology. Thus, the 3D-printed cushioning–antibacterial dual-function packaging aerogel with a shell–core structure (CNGA/C–AgNPs) was obtained. The CNGA/C–AgNPs packaging aerogel had good cushioning and resilience performance, and the average compression resilience rate was more than 90%. Although AgNPs was slowly released, CNGA/C–AgNPs packaging aerogel had an obvious antibacterial effect on E. coli and S. aureus. Moreover, the CNGA/C–AgNPs packaging aerogel was biodegradable. Due to the customization capabilities of 3D-printing technology, the prepared packaging aerogel can be adapted to more application scenarios by accurately designing and regulating the microstructure of aerogels, which provides a new idea for the development of food intelligent packaging. 相似文献
132.
An economical and facile synthesis of Nα‐Boc‐Nβ‐Cbz‐2,3‐diaminopropionic acid derivatives is reported. The key aspect of this method is employment of N‐Boc‐5‐oxazolidinone moiety to simultaneously provide proper protection of α‐amido and α‐carboxyl functional groups and affords the desired isocyanate 5 successfully by a Curtius rearrangement. The obtained intermediate 6 can be readily converted to various derivatives of Nα‐Boc‐Nβ‐Cbz‐2,3‐diaminopropionic acid by conventional procedure. 相似文献
133.
Yuushou Nakayama Takamichi Inaba Yosuke Toda Ryo Tanaka Zhengguo Cai Takeshi Shiono Hiroyuki Shirahama Chikara Tsutsumi 《Journal of polymer science. Part A, Polymer chemistry》2013,51(20):4423-4428
l ‐Lactide (l ‐LA) was polymerized in the presence of N‐methyldiethanolamine as an initiator and Sn(Oct)2 as a catalyst to give hydroxy‐telechelic poly(l ‐lactide) (PLLA‐diol) bearing a tertiary amine group at the center of the polymer chain. Successive chain extension of the PLLA‐diol with hexamethylene diisocyanate afforded PLLA‐based poly(ester‐urethane)s (PEU) with equally spaced tertiary amine groups. Treatment of the PEU with iodomethane converted tertiary amine groups to quaternary ammonium groups to give cationic ionomers (PEU‐MeI). The thermal, mechanical, hydrophilic, and biodegradation properties of the obtained polymers were investigated. The thermal properties of the PEUs and the PEU‐MeIs were similar each other. The PEU‐MeIs exhibited higher tensile modulus than those of the starting PEUs. The contact angles of water on the PEU‐MeIs were lower than those of the PEUs with similar NMDA content indicating their higher hydrophilicity. In compost degradation tests, the PEU‐MeIs showed slower degradation than those of the PEUs. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4423–4428 相似文献
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通过射频磁控溅射的方法制备Au-Ag-SiO2复合纳米金属颗粒膜.实验结果表明颗粒膜的光学吸收峰及共振波长的位置依赖于颗粒膜中金属的介电常数,粒子尺寸,金属的相对体积比;颗粒膜共振波长随着颗粒膜中Au和Ag相对体积比而改变,提高退火温度可以提高复和颗粒膜的光学吸收峰值. 相似文献
137.
Shaojing Bu Zhengguo Jin Xiaoxin Liu Haiyan Du Zhijie Cheng 《Journal of Sol-Gel Science and Technology》2004,30(3):239-248
Porous nanocrystalline TiO2 anatase thin films have been synthesized on glass substrates via a sol-gel dip-coating method. The coating sol was obtained by suppressed hydrolysis of Ti(OC4H9)4 through the addition of complexing molecules as stabilizers in an alcohol solution containing polyethylene glycol (PEG). Chemical changes taking place during the sol-gel process were discussed based on IR spectra analysis. A model concerning the pore formation was established to explain the role of PEG and solvent with core-shell configuration as double-templates. The structural characteristics of porous TiO2 films were found to greatly depend on the concentration and molecular weight of PEG, the types of stabilizing agents and solvents. The pore size of the films was tunable in the range of 10–500 nm and their surface area varied from 51 to 72 m2·g–1. 相似文献
138.
Stable solutions of conjugated poly(phenylene vinylene)s and poly(phenylene ethynylene)s in nematic liquid crystals are reported. The polymers all contain triptycene units fused into their backbones to obtain the high solubility needed to maintain solubility in complex liquid crystalline media. The polymer backbones align with the director of the nematic liquid crystal, and by applying electric fields the polymers can be reoriented. The polymers all displayed lower band gaps in the liquid crystal solvents relative to those obtained in standard solvents such as methylene chloride. Hence, the liquid crystal solution induces a chain-extended highly conjugated structure in the polymers, which is generally associated with optimization of the polymer properties. 相似文献
139.
可聚合非离子型乳化剂稳定的聚丙烯酰胺反相胶乳 总被引:5,自引:0,他引:5
近年来,新型可聚合乳化剂的研制及应用引起了人们的极大兴趣[1~4].目前报道的可聚合乳化剂都是水溶性的,用于正相乳液聚合中改善聚合物膜的性能及聚合物的加工性能[1],提高聚合物胶乳的稳定性以及制备功能化乳胶粒子等[5,6].本文合成了油溶性可聚合非离... 相似文献
140.