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1.
生物降解性聚酯   总被引:1,自引:0,他引:1  
本文阐述了生物降解性聚酯的主要产品,生物降解性聚酯的降解机理及生物降解性聚合物的存在问题和研究方向.  相似文献   

2.
合成生物降解性聚酯研究的进展   总被引:20,自引:0,他引:20  
对近年来采用化学法,主要是缩合聚合法及开环聚合法,合成生物降解性聚酯的研究进展作了综述。  相似文献   

3.
从四个方面综述了近年来聚对苯二甲酸乙二酯(PET)和聚对苯二甲酸丁二酯(PBT)生物改性的研究进展:(1)在聚酯合成中采用生物原料;(2)采用共聚技术制备可生物降解性共聚酯;(3)生物活性物质在聚酯中的引入改性,可提高其生物相容性和抗菌能力,在聚酯用于人造器官时,可使血管纤维原细胞的细胞增殖;(4)生物酶对聚酯进行水解改性,可减轻重量,并改善吸湿性、染色性等性能。  相似文献   

4.
以TiCl4为原料,采用溶胶-凝胶法制备了纳米级的TiO2,并用XRD和TEM等手段进行了表征,并以TiO2-TBOT(钛酸四丁酯)为催化剂,1,4-丁二醇、己二酸和对苯二甲酸二甲酯为原料制备了聚己二酸丁二醇酯和对苯二甲酸丁二醇酯的共聚物,对共聚物的相对分子质量、断裂拉伸强度和断裂伸长率进行了测试,以各反应的时间长短、共聚酯的分子量的高低和力学性能对催化剂性能进行了考察.并采用堆肥埋片法,以失重率作为降解性指标,考察了含芳香组分为40%、50%和60%摩尔分数的三种共聚酯的生物降解性.结果表明,纳米TiO2与TBOT的复合催化剂具有良好的催化性能,当TBOT/TiO2比例为1.2时,所制备共聚酯的重均分子量达到82000.在脂肪族聚酯中引入摩尔分数为40%~60%的芳香族组分,所制备的共聚酯具有较好的力学性能和生物降解性;且随着所含芳香组分的增多,生物降解性变差.  相似文献   

5.
近年来,作为生物降解高分子材料,脂肪族聚酯由于良好的生物降解性及生物相容性受到人们的广泛关注。脂肪族聚酯在环境友好材料和生物医用材料领域都具有极大的应用价值,目前,部分聚酯材料已经商品化。与此同时,脂肪族聚酯的合成方法尤其是活性开环聚合也成为学术界及工业领域的研究热点。采用开环聚合法得到的聚合产物化学组成精确、分子量分...  相似文献   

6.
淀粉/聚酯体系生物可降解材料   总被引:4,自引:0,他引:4  
主要从淀粉/聚酯共混、聚酯—淀粉—聚酯复合层、交联及生物降解性方面综述了近年来淀粉/聚酯体系的生物可降解材料的研究进展。  相似文献   

7.
用熔融缩聚法合成了一系列聚(丁二酸丁二醇酯丁二酸-1,4-环己烷二甲醇酯)无规共聚物。通过。H—NMR、FT—IR、DSC、TGA、XRD、酶降解测试等方法表征了材料的结构与性能。结果表明:合成得到的共聚酯为预期产物;共聚酯的晶体结构发生了改变,并产生了共晶行为;随着1,4-环己烷二甲醇(CHDM)含量的增加,产物的熔点由113.7℃降至64.6℃,然后升至114.2℃,玻璃化转变温度由-33.8℃单调升高至5.4℃;CHDM的引入增强了共聚酯的热稳定性;酶降解测试得出产物P51、P31具有良好的生物降解性,且P51降解最快。  相似文献   

8.
共聚酯PEIT-PEG结构与性能的研究   总被引:3,自引:0,他引:3  
PET与PEG共聚可改善PET的抗静电性,但PEG含量的增加,会使共聚物的结晶温度大幅度地降低,不利于纤维加工,且伴随着结晶的发生,纤维的抗静电性也受到影响。在共聚体系中添加间苯二甲酸(IPA),不仅能破坏大分子链结构的规整性、降低共聚酯的结晶性,而且能提高共聚酯纤雏的抗静电性能。用DSC与TG对共聚酯(PEIT-PEG)的聚集态结构、热性能、结晶性能等进行了表征。  相似文献   

9.
可生物降解聚酯酰胺共聚物的合成与表征   总被引:8,自引:0,他引:8  
刘孝波  朱方华 《合成化学》1999,7(4):354-358
以两种合成的酰胺二元醇和癸二酸为原料合成了可生物降解的聚酯酰胺共聚物,研究了该癸半晶性聚合物的合成、结晶及其生物降解性,并应用IR,^1H NMR,SEM及DSC进行了表征。  相似文献   

10.
聚十二烷二元酸丁二酯是长碳链脂肪族聚酯中的一种新的聚合物材料.近年来,随着对环境问题的日益重视,利用脂肪族聚酯容易水解的特性,开发生物降解脂肪族聚酯材料的研究得到广泛开展.目前脂肪族二元酸酯的研究大多是围绕聚丁二酸酯、聚乙二酸酯及其共聚酯这一类降解速度较快的材料进行的.虽然这些聚酯已有部分商品化,但远远不能满足对特定降解速率材料的需求.长碳链脂肪族聚酯由于其具有类似PE的结构特征,又兼具聚酯的结构特征,有望在可降解包装材料、书籍装订、服装用热熔胶等方面获得广泛的应用.  相似文献   

11.
With the increasing use of one-off plastic products, the environmental pollution resulted from the plastic waste has become more and more serious. So many scientists have focused their attention on developing biodegradable polymers to substitute the traditional unbiodegradable polymers in the manufacture of disposable products. Thus the plastic waste can be treated by landfill or composting technique. It has been found that aliphatic polyesters possess better biodegradability compared with oth…  相似文献   

12.
A series of aliphatic biodegradable polyesters modified with fumaric residues was synthesized by transesterification in the melt of dimethyl succinate, dimethyl fumarate and 1,4-butanediol. The amount of unsaturation, originating from the fumaric acid residues in the polyesters chains was varied from 5 to 20 mol%. The molecular structure and composition of the polyesters were determined by 1H NMR spectroscopy. The effects of the content of fumaric residues on the thermal and thermo-oxidative properties of the synthesized polyesters were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis. The degree of crystallinity was determined by DSC and wide angle X-ray scattering. The degrees of crystallinity of the unsaturated copolyesters were reduced, while the melting temperatures were higher in comparison to poly(butylene succinate). Biodegradation of the synthesized copolyesters was estimated in enzymatic degradation tests using a buffer solution with Rhizopus arrhizus lipase at 37 °C. Although the degree of crystallinity of the copolyesters decreases slightly with increasing unsaturation, the biodegradation is not enhanced suggesting that not only the chemical structure and molecular stiffness but also the morphology of the spherulites has an influence on the biodegradation properties. The highest biodegradability was observed for the copolyesters containing 5 and 10 mol% of fumarate units.  相似文献   

13.
A number of polyacrylic (PAA) and polymethacrylic (PMAA) acids have been synthesized by living anionic polymerization of the monomeric tert-butyl esters followed by subsequent hydrolysis of the corresponding polyesters. The necessary precautions were taken in order to assure good molecular weight control, as well as high yields in the polymerization reactions. The intermediate and final polymers were characterized by gel permeation chromatography and NMR-H1 spectrometry.  相似文献   

14.
Functionalized poly(lactic acid) having sulfur‐protected groups along the chain have been synthesized with the ultimate aim to obtain materials for reversible and degradable self‐assembly systems. The first step in the synthesis was the preparation of hydroxy‐(4‐methyl‐phenylsulfanyl)‐propionic acid and hydroxy‐(tritylsulfanyl)‐propionic acid. These sulfur‐functionalized hydroxy acids were subsequently used as comonomers in the condensation polymerization of lactic acid producing functionalized polyesters with thio‐protected groups along the chain. The ratio of functionalized hydroxyl‐acid in the copolymer was determined by the feed ratio. The polyesters obtained were amorphous and size exclusion chromatography analysis showed a monomodal distribution. When treated with iodine, the polyesters chains bearing the tritylsulfanyl side groups assembled with the formation of S? S bridges and the molecular weight increased accordingly. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

15.
Various phase behavior of blends of poly(vinyl ether)s with polyesters of two types (highly crystalline and less crystalline with different main‐chains) were examined using differential scanning calorimetry (DSC) and optical microscopy (OM). Effects of varying the main‐chain polarity of the constituent polyesters on the phase behavior of the blends were analyzed. Miscibility in PVME/polyester blends was found only in polyesters with backbone CH2/CO ratio = 3.5 to 7.0). Tg‐composition relationships for blends of PVME with highly crystalline polyesters (PBA, PHS) were found to differ significantly from those for PVME blends with less‐crystalline polyesters (PTA, PEAz). Crystallinity of highly crystalline polyester constituents in blends caused significant asymmetry in the Tg‐composition relationships, and induced positive deviation of blends' Tg above linearity; on the other hand, blends of PVME with less crystalline polyesters exhibit typical Fox or Gordon‐Taylor types of relationships. The χ parameters for the miscible blends were found to range from ?0.17 to ?0.33, reflecting generally weak interactions. Phase behavior was analyzed and compared among blends of PVME with rapidly crystallizing vs. less‐crystallizing polyesters, respectively. Effects of polyesters' crystallinity and structures on phase behavior of PVME/polyester blends are discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2899–2911, 2007  相似文献   

16.
Four poly(butylene adipate) (PBA) polyesters, the structure ranging from linear to highly branched, were synthesized and solution casted with poly(vinyl chloride) (PVC) in 20 or 40 wt % concentrations to evaluate the influence of polyester chain architecture on miscibility, surface segregation, and mechanical properties. The miscibility of PVC and polyesters is based on specific interactions between the carbonyl group in the polyester and PVC. These interactions cause a shift in the carbonyl absorption band in the FTIR spectra. The shifting of the carbonyl absorption band was more significant for all the 40 wt % blends compared with the blends containing 20 wt % of the same polyester. In the 20 wt % blends surface segregation and enrichment of polyester at the blend surface increased as a function of branching. However, all the films containing 40 wt % of polyester had similar surface composition. This is explained by better miscibility and stronger intermolecular interactions in the 40 wt % blends, which counteract the effect of branching on the surface segregation. High degree of branching resulted in poor miscibility with PVC and poor mechanical properties. A linear or slightly branched polyester structure, however, resulted in good miscibility and desirable blend properties. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1552–1563, 2007  相似文献   

17.
In previous report, we discovered that a novel improvement technique to enhance the thermal properties of poly(L ‐lactide)s (PLLAs) by terminal conjugation with 3,4‐diacetoxycinnamic acid (DACA). In this study, we clarified the mechanism of the enhancement of thermal stability by using commercial polyesters and polyethers. The effect of thermal improvement by the terminal conjugation of DACA on poly(DL ‐lactide), poly(ε‐caprolactone), and poly(ethylene glycol) was almost the same as about 100 °C increase. The amount of residual tin catalyst, which enhances the thermal degradation of polyesters, was reduced at undetected level after the terminal conjugation of DACA probably due to the removal of tin during DACA conjugation process. Furthermore, the π‐π stacking interactions of DACA units and the chemical protection of terminal hydroxyl groups, which enhances intramolecular scission, were also important for the high thermal stability. We clarified that the extreme high thermal stability by DACA conjugation was induced by these above mechanisms. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

18.
以苯甲醇、3-氯-1,2-丙二醇和固体光气等为原料,制备了一种五元环状碳酸酯4-苄氧甲基-1,3-二氧戊环2酮(BPC),并用IR、1H NMR、13C NMR、MS、元素分析对其进行了表征.在辛酸亚锡作用下制备了BPC均聚物及其与DL丙交酯(DL- LA)的共聚物,并进行了表征.结果表明,BPC可均聚也可与DL- LA共聚,为改善传统的生物降解型脂肪族聚酯的亲水性及在可降解聚合物中引入反应性基团提供了新的途径.  相似文献   

19.
Three series of terephthalate polyesters (copolyesters and terpolyesters) containing 70, 80, and 90 mol % of ethylene glycol respectively, 1,4‐cyclohexanedimethanol (CHDM) and isosorbide in varying ratios, were synthesized by melt polycondensation. It was found that only ~75 mol % of the feeding isosorbide was incorporated in the resulting polyesters and that their content in diethylene glycol oscillated between 2 and 4 mol %. The polyesters had weight‐average molecular weights in the 25,000–33,000 g mol?1 range and polydispersities between 2 and 2.5. The combined 1H and 13C NMR analysis revealed that the microstructure of all these polyesters was at random. They showed good thermal stability with decomposition temperatures above 400 °C. Their glass‐transition temperatures were observed to increase with the content in cyclic diols, this effect being more pronounced when isosorbide was the replacing comonomer. Only the series containing 90 mol % of ethylene terephthalate units was able to crystallize upon cooling from the melt. Compared isothermal crystallizations revealed that isosorbide was more effective than CHDM in repressing the crystallizability of PET. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

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