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981.
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Ao Sun Xinye He Xiao Ji Danrong Hu Meng Pan Linghong Zhang Zhiyong Qian 《中国化学快报》2021,32(7):2117-2126
Owing to the special fo rmation of photopolymerized hydrogels,they can effectively control the formation of hydrogels in space and time.Moreover,the photopolymerized hydrogels have mild formation conditions and biocompatibility;therefore,they can be widely used in tissue engineering.With the development and application of manufacturing technology,photopolymerized hydrogels can be widely used in cell encapsulation,scaffold materials,and other tissue engineering fields through more elaborate manufacturing methods.This review covers the types of photoinitiators,manu facturing technologies for photopolymerized hydrogels as well as the materials used,and a summary of the applications of photopolymerized hydrogels in tissue engineering. 相似文献
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Xiao Feng Yang Qiao Ling Li Zhi Ping Chen Lei Zhang You Zhou 《Journal of Thermal Analysis and Calorimetry》2013,112(2):567-571
Thermolysis behavior of flame-retardant copolyamide 66 (FR-PA66) in the presence of triaryl phosphine oxide (TPO) has been studied using different techniques such as differential scanning calorimetry, thermal gravimetric analysis, Fourier transform-infrared spectroscopy, and gas chromatography–mass spectrometry. The results indicate that TPO extends the thermolysis time of FR-PA66, and improves the thermolysis temperature. A three-stage mechanism for the decomposition of FR-PA66 has been proposed in this article. In the first stage, cleavage of P–C bond takes place in FR-PA66, while in the second stage, cleavage of polyamide chain occurs mainly. In the third stage, formation of cyclic compounds proceeds along with the formation of carbonized protective layer on the degraded polymer. 相似文献
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A new type of polyimide foam (PIF) was prepared and characterized based on a one‐pot process by the reaction of a first solution with different ratios of a second solution. The first solution was comprised of pyromellitic dianhydride (PMDA), N, N‐dimethyl formamide (DMF), methanol, water, surfactant, and catalysts, while the second solution contained polyaryl polymethylene isocyanate (PAPI). In the present study, the relationships among compositions, structures, and properties of PIFs were investigated. The results indicated that with the increase in the weight ratio of PAPI/(first solution), the foaming degrees of PIFs increased from 10.14 to 10.52 times and the apparent densities before postcure decreased from 15.96 to 14.51 kg/m3. The open cell contents, average sound absorption coefficients, and average cellular diameters of PIFs after postcure increased with increase in the weight ratio of PAPI/(first solution). The glass transition temperatures (Tg) of PIFs after postcure first increased from 287 to 299°C, then decreased to 292°C, and the 5% weight loss temperatures and 10% weight loss temperatures presented the same trend as well. The compressive and flatwise tensile properties scaled very well with the relative densities of the foams after postcure, with the highest compressive strength of 0.03 MPa and the highest flatwise tensile strength of 0.15 MPa. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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偏钒酸铵催化合成2-芳基取代苯并噁唑 总被引:2,自引:0,他引:2
在偏钒酸铵催化下,以2-氨基苯酚和芳醛为原料、乙醇为溶剂,在室温下合成了一系列2-芳基取代苯并噁唑类化合物.该方法具有操作简便、反应条件温和、产率高等优点. 相似文献
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