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Photoreactive and degradable hyperbranched (HB) copolymers with various 3,4‐dihydroxycinnamic acid (DHCA) compositions, poly(ε‐caprolactone)‐co‐poly(3,4‐dihydroxycinnamic acid) (PCL‐co‐PDHCA), were obtained by thermal melt‐polycondensation of PCL and DHCA. The HB structures and the branching degree (BD) of the PCL‐co‐PDHCA copolymers were confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR). The melting points (Tm) of the PCL‐co‐PDHCA copolymers changed depending on the PCL and DHCA composition by differential scanning calorimetry (DSC) measurements. Wide angle X‐ray diffraction (WXRD) analysis showed semi‐crystalline of the PCL and PCL‐co‐PDHCA polymers. The PCL‐co‐PDHCA copolymers showed good photoreactivities and fluorescent properties. Crosslinking of the cinnamoyl groups in the copolymers caused by UV irradiation affected the thermal stability and wettability slightly. Moreover, the hydrolysis experiments revealed that copolymers are facile degradable. 相似文献
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Celia Regao Antxon Martínez De Ilarduya Jos I. Iribarren Sebastin Muoz‐Guerra 《Journal of polymer science. Part A, Polymer chemistry》2000,38(15):2687-2696
A series of aregic poly(ester amide)s (a‐PEAT6) with ester/amide ratios (a : b) varying from 1 : 19 to 1 : 2 were prepared with L ‐tartaric acid, 6‐aminohexanol, and 1,6 hexanediamine as the starting materials. Polycondensation in a solution of the diamine with mixtures of pentachlorophenyl‐activated di‐O‐methyl‐L ‐tartaric and 6‐aminohexyl‐di‐O‐methyl‐L ‐tartaric acids led to a‐PEAT6(a : b), with the a : b ratio determined by the composition of the feed. The newly synthesized poly(ester amide)s were characterized by elemental analysis, size exclusion chromatography, and IR and NMR spectroscopy. They had number‐average molecular weights between 25,000 and 45,000 and were highly crystalline, showing melting temperatures ranging from 100 to 230 °C and glass‐transition temperatures oscillating between 50 and 100 °C. The thermal degradation of a‐PEAT6(a : b) began above 200 °C and concluded with a final weight loss between 60 and 90% of the initial mass. The process evolved with the formation of cyclic tartarimide units and extensive main‐chain scissions. The degradation mechanism is discussed in relation to the chemical composition and microstructure of the polymers. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2687–2696, 2000 相似文献
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Wen Huang Guang Yang Qingbo Xu Meixiao Zhan Lijuan Yao Honghui Li Fengfeng Xiao Zirun Chen Xiaoguang Zhao Wenting Li Wei Zhao Fujun Zhang Yong Li Ligong Lu 《Macromolecular bioscience》2023,23(4):2200442
Developing proper wound management via wound dressings represents a global challenge. Ideal wound dressings shall encompass multiple integrated functionalities for variable, complex scenarios; however, this is challenging due to the complex molecular design and synthesis process. Herein, polymer composites, cross-linked poly(styrene oxide-co-hexaphenylcyclotrisiloxane)/crosslinked poly(hexaphenylcyclotrisiloxane) (cP(SO-co-HPCTS)/cPHPCTS) with multiple functionalities are prepared by a one-step, open-air method using catalytic ring-opening polymerization. The introduction of a mobile polymer cP(SO-co-HPCTS) endows the composite with good flexibility and self-healing properties at human body temperature. The hydrophobic groups in the main chain provide hydrophobicity and good water resistance, while the hydroxyl groups contained in the end groups enable good adhesion properties. Drugs can be efficiently loaded by blending and then sustainably release from the polymer composite. The material can rapidly degrade in a tetrahydrofuran solution of tetrabutylammonium fluoride due to its Si O Si bonds. The facile, one-step, open-air synthesis procedure and multiple functional properties integrated into the composites provide good prospects for their extensive application and batch production as wound dressing materials. 相似文献