可降解高分子材料的制备及其降解机理

随着科学技术的发展,工业生产中对绿色环保型材料的需求量越来越大.研究并开发可降解高分子材料能够极大地减小化石原料短缺、环境污染严峻等问题.在阐述可降解高分子材料降解机理(如生物降解、光降解、热降解以及溶剂降解等)的基础上,对可降解高分子材料的制备方法进行了综述,其中,包括生物基可降解高分子、合成型可降解高分子、共混型可...     

生物降解高分子材料研究进展

介绍了生物降解高分子材料的概念和分类,并结合具体实例详细论述了目前国内外在天然、微生物合成、化学合成和掺混型等四类生物降解高分子材料方面的研究方向及最新研究进展。     

可生物降解高分子材料的研究与进展

高分子材料难以自然降解,会造成环境污染。可生物降解高分子材料在其使用寿命后,可以自行降解,是未来高分子材料发展的重要方向之一。简要介绍了生物降解高分子材料及其分类,探讨了可生物降解材料的降解机理、影响材料生物降解的因素和生物降解材料的制备方法、评价方法、研究与应用概况,并指出了可生物降解高分子材料未来发展的方向。     

生物降解性高分子材料的发展和应用

综述了生物降解性高分子材料的社会需求及其应用领域，重点介绍了几种典型的生物降解性材料，如脂肪族聚酯、纤维素、淀粉系等聚合物的研究和开发现状。对其未来发展作了展望。     

降解性高分子材料的研究开发进展

综述了生物降解高分子材料,光降解高分子材料和光－生物降解高分子材料的种类、制备方法、性能及其应用,指出了降解高分子材料存在的问题方向,通过比较认为光降解高分子材料技术比较成就,完全生物降解高分子材料和光－生物降解高分子材料发展前景看好,并对今后的发展提出了建议。     

聚乳酸市场潜力巨大——聚乳酸生产与应用及改性研究

近年来，生物降解性高分子材料的研究发展迅速，并且在不同领域的开发和应用日益广泛。生物降解性高分子材料是指在使用过程中能够保持所需的性能，使用后能被自然界中存在的微生物分解成低分子化合物，并最终变成水和二氧化碳等无机物的一类高分子材料。聚乳酸是1种典型的生物降解性高分子材料，具有良好的生物相容性、生物降解性能。最终降解产物为二氧化碳和水，由机体正常的新陈代谢排出体外，是一种具有广泛应用前景的生物医用高分子材料，如可吸收手术缝合线、烧伤覆盖物、骨折内固定材料等。有关聚乳酸的研究一直是生物降解性高分子材料研究领域的热点。     

普通聚烯烃类塑料生物降解研究进展

介绍了高分子材料生物降解的概念、生物降解的作用方式,影响生物降解的因素,并且分析了高分子聚合物生物降解的研究现状,从添加易生物降解的填料法和添加光氧助剂-生物降解法这两个方面总结了普通聚烯烃类塑料生物降解研究进展,指出了今后研究的重点。     

生物降解性高分子材料(续)

本文综述了国内外生物降解高分子材料的研究现状和发展方向，分析了国内外生物降解研究和生产中存在的几个问题，结合我国的国情，对我国未来生物降解高分子的研究和发展提出了几点建议。     

生物降解性高分子材料

本文综述了国内外生物降解高分子材料的研究现状和发展方向，分析了国内外生物降解研究和生产中存在的几个问题，结合我国的国情，对我国未来生物降解高分子的研究和发展提出了几点建议。     

生物降解高分子材料的研究新进展

综述了生物降解高分子材料制备方法和降解机理的研究新进展 ,并讨论了结构、组成、形态和外界条件等因素对均聚物、共聚物和高分子共混物生物可降解性的影响 ,简述了生物降解高分子材料在生物医学、包装和农业领域的潜在应用。     

Antibacterial activity of natural polymer gels and potential applications without synthetic antibiotics

Antibiotics' use has increased, resulting in disadvantages like patients' drug resistance. Consequently, urgent action is required to develop a new generation of antibacterial agents. Most antibacterial platforms still require a modification with further antibacterial agents (e.g., antibiotics) for adequate antibacterial efficiency. Thus, a nonantibiotic methodology is immediately needed. Furthermore, bactericidal agents used for this purpose are usually based on metal nanoparticles, carbon materials, and polymers. Still, chemicals, antibiotics, and biocides lead to environmental damage. Therefore, the help of biocompatible yet durable materials and polymers is highly appreciated. In addition, if a polymer is not biodegradable, it will remain in the environment for more than one hundred years due to its low degradation rate. Moreover, non-biodegradable polymers are harmful to in vivo applications. Hence, the use of biodegradable and non-toxic materials has received many considerations. Over the last few years, the design and synthesis of new polymer gels have gained increasing attention. A polymer gel, also known as a hydrogel, is a three-dimensional and cross-linked network filled with water or other liquid solvents. Besides, the hydrogels supercritical drying method results in aerogels, and the freeze-drying method generates cryogels, where their porous and sponge-like structures are preserved. Additionally, antibacterial polymer gels are a new generation of polymers considered attractive due to their unique properties. The most recent studies and the latest innovations in polymer gels and hybrid polymers with intrinsic antibacterial properties were discussed in the present review. The reviewed studies from 2015 to April 2022 showed a tremendous revival in research about biopolymer hydrogel, aerogel, and cryogel as antibacterial agents.     

合成高分子聚合物生物降解研究进展

概述了目前常见的各类合成聚合物以及生物降解塑料的生物降解研究成果和进展,着重介绍了合成聚酯类化合物的生物降解情况,并为将来可降解高分子聚合物的开发研究提供了参考。     

生物降解性高分子材料

简述了生物降解性高分子的生物降解机理,阐述了影响高分子材料生物降解的因素,重点介绍了生物降解 性高分子研究现状。     

PBAT/PLA/cellulose nanocrystals biocomposites compatibilized with polyethylene grafted maleic anhydride (PE-g-MA)

The use of biodegradable polymers has grown exponentially due to their lower environmental impact when compared to conventional polymers. In this sense, biocomposites are an alternative due to their promising properties, maintaining biodegradability. For this purpose, in the present study, a biodegradable biocomposite of PBAT (poly [butylene adipate co-terephthalate]) and PLA (polylactide) blend containing cellulose nanocrystals (CNC) were obtained, using polyethylene grafted with maleic anhydride (PE-g-MA) as a coupling agent. Seven formulations were produced by extrusion and had their structure, morphology, thermal, and rheological properties analyzed. The results showed a significant improvement of adhesion among the components using PE-g-MA as a coupling agent. Moreover, CNC and PE-g-MA increased the PLA crystallinity degree and reduced the complex viscosity. These results are unprecedented in the literature using these compositions and extrusion processing conditions. Therefore, these new insights provide a vast horizon for the use of biodegradable mixtures using PBAT/PLA and CNC.     

Recent developments in nanocellulose-based biodegradable polymers,thermoplastic polymers,and porous nanocomposites

Nanocellulose has generated a great deal of interest as a source of nanometer-sized reinforcement, because of its good mechanical properties. In the last few years, nanocellulose has also attracted much attention due to environmental concerns. This review presents an overview of recent developments in this area, including the production, characterization, properties, and range of applications of nanocellulose-based biodegradable polymers, thermoplastic polymers, and porous nanocomposites. After explaining the unique properties of nanocellulose and its various preparation techniques, an orderly introduction of various nanocellulose-reinforced biodegradable polymers such as starch, proteins, alginate, chitosan, and gelatin is provided. Subsequently, the effects of nanocellulose on the properties of thermoplastic polymers such as polyamides, polysulfone, polypropyrol, and polyacronitril are reported. The paper concludes with a presentation of new finding and cutting-edge studies on nanocellulose foam and aerogel composites. Three different types of aerogels, i.e., pristine nanocellulose-based aerogels, modified nanocellulose-based aerogels, and nanocellulose-based templates for aerogels, are discussed, as well as their preparation techniques and properties. In the case of foam composites, the research focus has been on two major preparation techniques, i.e., solvent-mixing/foaming and melt-mixing foaming, their respective challenges, and the properties of the final composites. In some cases, a comparison study between cellulose nanocrystals and cellulose nanofiber-reinforced biodegradable polymers, thermoplastics, and porous nanocomposites was carried out. Considering the vast amount of research on nanocellulose-based composites, special emphasis on such composites isprovided at the end of the review.     

Chia seeds to develop new biodegradable polymers for food packaging: Properties and biodegradability

Chia seeds are a promising raw material for the development of biodegradable and edible polymers due to their composition and properties. This study aimed to evaluate the effects of drying process of chia mucilage (oven and freeze-drying) and the incorporation of chia oil in films for food packaging. The films were formed by casting using chia mucilage and glycerol. The polymers developed were evaluated by physicochemical properties, microstructure, thermal properties, and biodegradation. The drying process of mucilage and oil incorporation in films affected mainly mechanical and color properties. Freeze-dried mucilage resulted in superior mechanical performance. Differences were caused by the effect of drying process in the molecular structure of chia mucilage and the incorporation of oil among the polymer chains. Chia mucilage films were completely soluble in water and biodegraded in a short time in soil. These films are promising biodegradable polymers for the development of eco-friendly food packaging and edible sachets for small pre-measured portions, preventing environment pollution and facilitating product consumption.     

Biodegradable synthetic polymers: Preparation, functionalization and biomedical application

Biodegradable polymers have been widely used and have greatly promoted the development of biomedical fields because of their biocompatibility and biodegradability. The development of biotechnology and medical technology has set higher requirements for biomedical materials. Novel biodegradable polymers with specific properties are in great demand. Biodegradable polymers can be classified as natural or synthetic polymers according to the source. Synthetic biodegradable polymers have found more versatile and diverse biomedical applications owing to their tailorable designs or modifications. This review presents a comprehensive introduction to various types of synthetic biodegradable polymers with reactive groups and bioactive groups, and further describes their structure, preparation procedures and properties. The focus is on advances in the past decade in functionalization and responsive strategies of biodegradable polymers and their biomedical applications. The possible future developments of the materials are also discussed.     

Synthesis and processability into textile structures of radiopaque,biodegradable polyesters and poly(ester‐urethanes)

Radiopaque biodegradable polymers have been synthesized by ring‐opening polymerization of l /dl ‐lactide and caprolactone with the iodine‐containing starter molecule 2,2‐bis(hydroxymethyl)propane‐1,3‐diyl bis(2,3,5‐triiodobenzoate) followed by chain elongation with a diacid chloride or diisocyanates. The resulting polyesters and poly(ester‐urethanes) exhibited a radiopacity of 60?124% relative to an aluminium sample of the same thickness. The polymers were processed into monofilament fibres by melt‐spinning and into fibre meshes by electrospinning. All polymers were biodegradable in simulated body fluid medium under in vitro conditions and showed an excellent in vitro cytocompatibility even after several months of hydrolytic degradation. A current drawback is the relatively low tensile strength of the polymer monofilaments, which needs to be improved for applications as textile structures. Nevertheless, the new radiopaque and biodegradable polymers are promising candidates in fields of application where radiopacity of implants is an important parameter.     

Polyhydroxyalkanoates: biodegradable polymers with a range of applications

Increased and accelerated global economic activities over the past century have led to interlinked problems that require urgent attention. The current patterns of production and consumption have raised serious concerns. In this context, greater emphasis has been put on the concept of sustainable economic systems that rely on technologies based on and supporting renewable sources of energy and materials. Average UK households produce around 3.2 million tonnes of packaging waste annually whereas 150 million tonnes of packaging waste is generated annually by industries in the UK. Hence, the development of biologically derived biodegradable polymers is one important element of the new economic development. Key among the biodegradable biopolymers is a class known as polyhydroxyalkanoates. Polyhydroxyalkanoates (PHAs) are a family of polyhydroxyesters of 3‐, 4‐, 5‐ and 6‐hydroxyalkanoic acids, produced by a variety of bacterial species under nutrient‐limiting conditions with excess carbon. These water‐insoluble storage polymers are biodegradable, exhibit thermoplastic properties and can be produced from renewable carbon sources. Thus, there has been considerable interest in the commercial exploitation of these biodegradable polyesters. In this review various applications of polyhydroxyalkanoates are discussed, covering areas such as medicine, agriculture, tissue engineering, nanocomposites, polymer blends and chiral synthesis. Overall this review shows that polyhydroxyalkanoates are a promising class of new emerging biopolymers. Copyright © 2007 Society of Chemical Industry