不饱和脂肪族聚酯生物降解性的研究

以1，4-反丁烯二酸和一缩二乙二醇（DEG）为原料，采用缩聚法合成端羟基不饱和聚酯，并采用红外光谱分析（FT—IR）、羟值、酸值、黏度等对所得聚合物进行表征，确认了其分子结构．对其降解性进行研究，并且与1，4-丁二酸与一缩二乙二醇合成的饱和脂肪族聚酯进行了对比。研究结果表明，不饱和脂肪族聚酯和饱和脂肪族聚酯的生物降解性差别不大，也就是双键的引入对其生物降解性没有大的影响；但是不饱和脂肪族聚酯膜经过高温处理后，双键会打开发生交联，而交联后的不饱和脂肪族聚酯的生物降解性变差，而且交联度越高，生物降解性越差。     

缩聚法合成生物可降解聚酯研究进展

本文从分子设计的角度,综述了缩聚法合成生物可降解聚酯的研究进展,涉及脂肪族聚酯和含有芳香组分聚酯的合成。其中,对脂肪族聚酯 聚乳酸的缩聚合成,以及可再生资源用于聚酯的合成进行了重点介绍。同时也对一些合成聚酯的生物降解性能与结构的关系进行了讨论。     

PBS及其共聚酯生物降解性能的研究进展

综述了PBS(聚丁二酸丁二醇酯)、PBS基脂肪族共聚酯,PBS基芳香族共聚酯的结构和生物降解性能,并分别总结了它们的结构和生物降解性能之间的关系.PBS基脂肪族共聚酯分为线型PBS基脂肪族共聚酯和枝状PBS基脂肪族共聚酯,分别对它们进行了介绍.得出了PBS及其共聚酯的结构、分子量、聚酯形态、熔点、结晶度等与共聚酯的生物降解性之间的关系.     

生物降解性脂肪族聚酯改性的研究进展

综述了脂肪族聚酯改性制备生物降解性聚酯的研究进展.在聚酯中引入刚性链段(即将脂肪族聚酯与芳香族、液晶基元共聚合)可改善聚酯的加工性能;在聚酯中引入亲水基大分子(即将脂肪族聚酯淀粉共混或与聚乙二醇共聚合)可改善聚酯的亲水性能.今后脂肪族聚酯改性研究的重点将解决功能化基团的引入、合成路线的简化、成本的降低及改性的效果等方面的问题.     

新型绿色材料——脂肪族聚酯

近二十年来,人类正面临着在合成材料方面的挑战。一类以聚乳酸及其同系物为代表的、可生物降解的新型合成脂肪族聚酯则有可能成为21世纪的一种“绿色材料”。本文重点介绍了这类脂肪族聚酯的合成方法、性能特征及其应用前景。     

功能化可降解脂肪族聚酯的研究进展

对生物可降解脂肪族聚酯进行功能化改性可以有效设计并裁剪分子结构,调控材料的生物相容性、生物降解性以及改善聚酯的反应活性,是目前生物医用材料和食品包装材料领域研究的热点。从聚酯的分子设计、化学结构、合成方法以及性能等方面综述了近年有关生物可降解脂肪族聚酯的研究进展,重点阐述了功能基团为羟基、氨基、不饱和键和叠氮基等的脂肪族聚酯的研究现状。并对可降解脂肪族聚酯未来的发展趋势及应用前景进行了展望。     

脂肪族聚酯的合成及降解性能研究

通过熔融和溶液结合法合成了脂肪族聚酯—聚丁二酸丁二醇酯(PBS)、丁二酸丁二醇酯-己二酸丁二醇酯共聚物(P(BS-co-BA))和丁二酸丁二醇酯-癸二酸丁二醇酯共聚物(P(BS-co-BSe)),并对其进行了生物降解实验。采用GPC测定了脂肪族聚酯的分子量及其分布,并采用熔点仪测定了聚酯的熔点。得到脂肪族聚酯分子量、熔点以及分子结构对称性和降解之间的关系。     

熔融共混工艺制备的聚(乳酸)弹性体共混体及其表征

<正>研究可生物降解聚合物的理由很多。上涨的油价和环境问题迫使很多研究人员用生物基聚合物开发容易降解的材料。近十年来,潜在自然资源的探索与合成一直是令人感兴趣的课题。有2类可生物降解聚合物:(1)农业聚合物(多糖、蛋白质等);(2)聚酯(芳香族和脂肪族聚酯)。脂肪族聚酯由于其性能,所以无论是均聚物还是共聚物都具有用作可生物降解聚合物的潜力。     

以反丁烯二酸合成的不饱和脂肪族聚酯的生物降解性研究

以反丁烯二酸、一缩二乙二醇和1,4-丁二醇为原料,采用熔融缩聚法合成了不饱和脂肪族聚酯和共聚酯,在37℃下,用含有脂肪酶的磷酸缓冲溶液对聚酯的生物降解性进行了研究,讨论了聚酯结构、组成及C=C双键的交联度对生物降解性的影响。结果表明,对于粘稠液体状的聚酯,C=C双键的引入,没有明显的改变其生物降解性;对于固体状的聚酯,C=C双键引入后,熔点(Tm)和结晶度增加;聚酯部分降解后,其热力学性能(Tm、-ΔHm)和结晶度都升高;对于交联后的聚酯,交联度越高,生物降解性越差。     

可降解聚酯酰胺新材料研制成功

以聚烯烃类高分子/淀粉共混物等可光降解或生物降解的包装材料、农用材料,不可能实现百分之百的生物降解,从而形成白色污染和二次白色污染。脂肪族聚酯可生物降解高分子材料,则由于只能采用特殊的合成方法和工艺获得,致使材料价格昂贵,难以推广。中国科学院成都有机化学所研究人员最近研制出可完全降解的聚酯酰胺新材料,并成功应用于一次性餐具、薄膜、纤维等。该技术具有连续化、制品质量稳定的特点,研究人员用可生物降解聚酯酰胺及共聚物制备了一次性餐具、可生物降解薄膜、纤维和各种色母料,其力学性能、生物降解性、毒性等都符合应用要…     

Branched aliphatic polyesters by ring-opening (co)polymerization

The rapid development of biodegradable and biocompatible materials for biomedical applications is reflected in the search for new methods for aliphatic polyester modification applicable in this field. One possible approach is modification by changes to the polymer topology.This review covers the main methods of synthesis of branched aliphatic biodegradable and biocompatible (co)polyesters, where the ring-opening polymerization (ROP) of cyclic esters or cyclic carbonates is the leading process. First, literature examples of ring-opening multibranching polymerization (ROMBP) of AB₂-type hydroxyl-substituted cyclic lactones, lactides and carbonates are cited followed by the presentation of the application of AB-type cyclic esters and additionally AB₂ cyclic ethers or esters as “branching monomers” for the synthesis of branched polyesters based on polycaprolactone (PCL), polylactide (PLA) and polyglycolide (PGA). In the following part, methods involving the combination of the ROP of AB-type cyclic esters and condensation processes leading to branched structures are summarized. Other related strategies leading to “dendri-star” or “core–shell” copolyesters are also discussed. Several examples of approaches to PCL and PLA graft copolymer syntheses are also shown. The advantages and disadvantages of the presented methodologies of branched polyester synthesis are highlighted. Finally, the influence of the branched structure on the properties of the presented class of polyesters, important from the application point of view, is considered.     

PBS基聚酯合成工艺的研究进展

PBS(聚丁二酸丁二醇酯)是种具有良好生物降解性的聚酯塑料,对PBS基聚酯的合成进行了总结和比较,介绍了PBS基聚酯合成的研究进展。指出进一步优化合成工艺来合成高分子量的PBS基聚酯仍然是一项挑战性的工作。     

脂肪族聚酯可降解材料的研究进展

综述了脂肪族聚酯的合成方式,介绍了脂肪族聚酯的亲水改性和共聚改性,并对脂肪族聚酯的发展方向进行了展望。     

脂肪族聚酯的合成与结晶性能

以脂肪族二醇和二羧酸或二羧酸二甲酯为原料合成出了系列脂肪族聚酯，采用差热分析的方法研究了其结晶性能，探讨了将脂肪族聚酯用于研制蓄热调温纤维的可能性.     

聚丁二酸丁二醇酯合成研究的进展

对聚丁二酸丁二醇酯的合成进行了总结和比较,指出通过寻找好的催化剂和进一步优化合成工艺来合成高分子质量的聚丁二酸丁二醇酯仍然是一项挑战性的工作。     

Biologisch abbaubare Polyester-Copolymere aus petrochemischen und nachwachsenden Rohstoffen

Biological Degradable Polyester Copolymers from Petrochemical and Renewable Raw Material. Synthetic, biodegradable aliphatic polyesters often do not provide optimal properties of application (e.g. melting point of polycaprolactone: 60°C). Material properties of such polyesters can be improved by introducing aromatic compounds into polymers. It could be shown that random aliphatic/aromatic copolyesters consisting of components like 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, adipic acid, sebacic acid and terephthalic acid (35–55 mol-% with regard to the diacid components) exhibit melting points of up to 145°C. These copolyesters are still biodegradable making this material of great commercial interest. Significant weight losses of polyester films could be observed in three months soil burial experiments(up to 40mol-% terephthalic acid) and in compost simulation tests at 60°C (up to 50 mol-% terephthalic acid). From degradation experiments with aromatic model oligoesters from terephthalic acid and 1,2-ethanediol (1,3-propanediol, 1,4-butanediol, respectively) it could be concluded that, aromatic intermediates (oligomers) will be assimilated very fast by microorganisms, if the degree of polymerization is one or two. It seems that longer oligomers are not accessable for an enzymatic attack, but will probably be hydrolyzed chemically at elevated temperatures (60°C), too. Using especially screened thermophilic microorganisms (55°C) on agar plates and analysis of residual material by size exclusion chromatography, the above mentioned finding could be confirmed. Some of the components of polyesters, described here can be obtained from renewable resources. For instance. 1,3-propanediol can by produced by a fermentation process from glycerol and a number of aliphatic dicarboxylic acids are available from natural oils. This option can make biodegradable high-tech polyesters with a defined structure part of natural cycles.     

聚丙交酯及可降解脂肪族聚酯类纤维的结构与生物降解性能

以聚丙交酯为代表讨论了可生物降解聚酯类纤维的结构特征与生物降解性能,对聚酯类纤维生物降解的机理、影响因素进行分析,指出聚合物的分子质量及分子链结构、聚集态结构、环境的温度、湿度、pH值及酶种类等因素对其降解性能有明显的影响,合理控制这些因素,可对其降解速度实现人为控制,以适应不同用途的需要.     

Organic acids catalyzed polymerization of ε‐caprolactone: Synthesis and characterization

Environmentally friendly organocatalytic synthesis of aliphatic polyesters was studied. The catalysis investigated is novel, and lends itself well to the potential production of valuable biodegradable products. The reactions were based on an organic acids‐catalyzed ring‐opening polymerization of ε‐caprolactone with fatty acid derivatives as the initiator and were performed in the absence of solvents. The chemical structures of the functionalized polymers were confirmed by ¹H and ¹³C‐NMR spectra. Polymers with different molecular weights, in the range 10,900–15,200 were obtained in the presence of fumaric acid as catalyst. The thermal properties of the functionalized PCLs were determined by modulated differential scanning calorimetry and thermogravimetric analysis. The MDSC results verified that the crystallinity and the melting point of the lipid‐functionalized polymers were lower than that of the unfunctionalized poly(ε‐caprolactone). The hydrolytic degradation of the functionalized polymer was also investigated. The result shows the degradation rate was affected by the presence of oleic acid derivatives in the polymer molecule. The lipid‐functionalized polymers synthesized by the metal‐free polymerization systems seem to be suitable biodegradable polyesters for use in biomedical and pharmacological applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011