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81.
生物可降解聚丁二酸乙二醇酯的合成与降解性能研究 总被引:2,自引:0,他引:2
以丁二酸和乙二醇为原料,直接熔融聚合,合成了高相对分子量的聚丁二酸乙二醇酯(PES),用FTIR,1H-NMR表征其结构;考察了不同聚酯反应催化剂对其聚合反应的影响,结果表明:三氧化二锑的催化效果是最佳的。同时,利用酶降解和体外水解的方法,对聚合物降解性能进行研究,结果表明:PES是一种可生物降解的聚合物,且在体外具有一定的降解性。 相似文献
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以丁二酸(SA),1,4-丁二醇(BDO)为原料,通过熔融聚合法合成聚丁二酸丁二醇酯(PBS)。通过对催化剂筛选及用量、缩聚反应温度、总反应时间和酸醇比等因素对产品粘均分子量影响的探讨,优化出了熔融法合成PBS的最佳工艺条件:选择SnCl2做催化剂,用量在2%(以催化剂加入SA的质量比表示),缩聚反应温度在230℃,总反应时间5h,在酸醇配比为1∶1.1时,反应得到的PBS产品的粘均分子量最大,粘均分子量为5.14×104g/mol,产品颜色为白色。用IR、TG、1H-NMR等表征证明产品合成成功。 相似文献
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以早籼米淀粉为原料,采用水相体系制备不同黏度的辛烯基琥珀酸淀粉酯,并对其糊化特性、冻融稳定性及在鸡肉灌肠中的应用进行研究。结果表明:淀粉经酸解和辛烯基琥珀酸酐改性后,可以得到不同黏度的辛烯基琥珀酸淀粉酯,具有良好的冻融稳定性。在鸡肉灌肠中应用时,加入早籼米辛烯基琥珀酸淀粉酯的鸡肉灌肠与加入木薯变性淀粉的鸡肉灌肠相比较,其硬度、弹性和咀嚼性都有不同程度的提高(P<0.05)。扫描电子显微镜分析显示,添加木薯变性淀粉的样品,内部结构比较蓬松,而添加早籼米OSA-H6的样品,其内部组织则相对紧实细腻。该研究表明,辛烯基琥珀酸酐改性淀粉(烯基琥珀酸淀粉酸)可以改善肉制品的质构特性,在肉制品中具有潜在的应用价值。 相似文献
85.
Yihe Zhang Bo Lu Fengzhu Lv Wenmin Guo Junhui Ji Paul K. Chu Changan Zhang 《应用聚合物科学杂志》2012,126(2):756-761
Polymeric foams have many advantages such as light weight, high specific strength, strong energy absorption, as well as good sound and thermal insulation. Unfortunately, most polymeric foams such as polyvinyl chloride foams do not undergo natural degradation and thus giving rise to white pollution to the environment. Here, we report the preparation and properties of poly (butylene succinate) (PBS) foam which is a biodegradable plastic. Ammonium bicarbonate is used as the foaming agent during the formation of the PBS foam by the molding method, and under the optimal conditions of 5 wt % ammonium bicarbonate, 10 MPa pressure, and 5 min pressing time, the pristine PBS foam with the smallest bulk density can be obtained, whereas under the conditions of 5 wt % ammonium bicarbonate, 7.5 MPa pressure, and 7 min pressing time, the toughening PBS foam has the smallest bulk density. Adding talc as a nucleating agent can reduce the bulk density of the foam and in this case, an NH4HCO3 content of 3 wt % yields the best result. Moreover, addition of plasticizers can effectively improve the mechanical properties of the products. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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The miscibility of poly(butylene succinate) (PBS)/poly(butylene thiodiglycolate) (PBTDG) blends was investigated by DSC technique. PBS and PBTDG were completely immiscible in as blended‐state, as evidenced by the presence of two Tgs at ?34 and ?48°C, respectively. The miscibility changes upon mixing at elevated temperature: the original two phases merged into a single one because of transesterification reactions. Poly(butylene succinate/thiodiglycolate) block copolymers, prepared by reactive blending of the parent homopolymers, were studied to investigate the effects of transesterification reactions on the molecular structure and solid‐state properties. 13C‐NMR analysis evidenced the formation of copolymers whose degree of randomness increased with mixing time. Thermal characterization results showed that all the samples were semicrystalline, with a soft rubbery amorphous phase and a rigid crystal phase whose amount decreased by introducing BTDG units into the PBS chain (20 ≤ χc ≤ 41). Lastly, the mechanical properties were found strictly related to crystallinity degree (χc), the random copolymer, exhibiting the lowest elastic modulus (E = 61 MPa) and the highest deformation at break (εb (%) = 713). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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《分离科学与技术》2012,47(2):215-223
The carrier mediated transport of Cu2+ ions from an aqueous medium has been examined. The ability of Erythromycin Ethyl Succinate (EES) as a carrier to form a complex with Cu2+ ions and transport them to the receiving phase is reported. The fundamental parameters influencing the transport of Cu2+ ions such as the pH in the source and receiving phases and concentration of the stripping agent in the receiving phase have been optimized and accordingly, the amount of Cu2+ transported across the liquid membrane after 5 h was 94.3 ± 1.8% in the presence of L-histidine as a suitable stripping agent. Moreover, the selectivity and efficiency of Cu2+ ions transport from aqueous solution over other cations in ternary and quaternary mixtures have been investigated. The results indicate that our fabricated membrane is very sensitive toward Cu+2 ions in the presence of heavy metal ions. 相似文献
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