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1.
In this study, blends of the bio-based poly(limonene carbonate) (PLimC) with different commodity polymers are investigated in order to explore the potential of PLimC toward generating more sustainable polymer materials by reducing the amount of petro- or food-based polymers. PLimC is employed as minority component in the blends. Next to the morphology and thermal properties of the blends the impact of PLimC on the mechanical properties of the matrix polymers is studied. The interplay of incompatibility and zero-shear melt viscosity contrast determines the blend morphology, leading for all blends to a dispersed droplet morphology for PLimC. Blends with polymers of similar structure to PLimC (i.e., aliphatic/aromatic polyester) show the best performance with respect to mechanical properties, whereas blends with polystyrene or poly(methyl methacrylate) are too brittle and polyamide 12 blends show very low elongations at break. In blends with Ecoflex (poly(butylene adipate-co-terephthalate)) and Arnitel EM400 (copoly(ether ester)) with poly(butylene terephthalate) hard and polytetrahydrofuran soft segments) a threefold increase in E-modulus can be achieved, while keeping the elongation at break at reasonable high values of ≈200%, making these blends highly interesting for applications.  相似文献   
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合成生物学在生物基塑料制造中的应用   总被引:1,自引:0,他引:1  
徐彦芹  杨锡智  罗若诗  黄玉红  霍锋  王丹 《化工学报》2020,71(10):4520-4531
合成生物学是以工程学思想为指导,对天然生物基因组进行改造和重构,合成新的生物元件,构建新的代谢途径,生产新产品或获得新表型的新兴学科。生物基塑料是以天然物质为原料在微生物作用或化学反应下生成的塑料。利用合成生物学改造工程菌株的方法制备合成生物基塑料已经成为学术界和产业界关注的热点。本文综述了合成生物学的发展和重要的合成生物学技术,重点综述了利用合成生物学技术构建聚羟基烷酸酯、尼龙、聚乳酸和丁二酸丁二醇酯等生物基塑料聚合物单体及其衍生物的代谢途径和工程优化领域的研究进展。  相似文献   
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The renaissance of the bio‐based chemical industry over the last 20 years has seen an ever growing interest in the synthesis of new bio‐based polymers. The building blocks of these new polymers, so called platform molecules, contain significantly more chemical functionality than their petrochemical counterparts (such as ethene, propene and para‐xylene). As a result bio‐based polymers often contain greater residual chemical functionality in their chains, with groups such as alkenes and hydroxyls commonly observed. These functional groups can act as sites for post‐polymerization modification (PPM), thus further extending the range of applications for bio‐based polymers by tailoring the polymers' final properties. This mini‐review highlights some of the most recent and compelling examples of how to make use of bio‐based polymers with residual functional groups for PPM. It also looks at how the emerging interdisciplinary field of enzymatic polymer synthesis allows for increased functionality in polymers by avoiding side‐reactions as a result of milder reaction conditions, and additionally offers an alternative means of polymer surface modification. © 2018 Society of Chemical Industry  相似文献   
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化学催化与酶催化复合法制备生物基化学品可兼具生物催化剂的高效、高选择性和化学催化剂的稳定性(高温下)等优点,且原料易得、工艺简捷高效、环境友好,以化学/酶复合催化一步法反应制备糖醇、氨基酸和其他生物基化学品中的应用来阐述此方法的优势和意义,并对其在生物质炼制过程的应用进行了展望。  相似文献   
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Finding an inexpensive and effective clean energy electrocatalyst is highly important for the new generation of photovoltaic devices. Herein, we report a facile and universal in situ co-precipitation strategy to load three novel tantalum-based compounds (NiTa2O6, MnTa2O6, and AlTaO4) on honeycomb-like bio-based carbon (HBC) frameworks. The HBC framework with unique honeycomb-like network structure serves as a support material in nanohybrids that can provide rich surface active sites and rapid electron transport channels for triiodide reduction reaction. The adoption of widely available and abundant biomass-derived carbon into tantalum-based compounds markedly boosts electrocatalytic properties of nanohybrids and exhibits robust corrosion resistance because nanohybrids adequately utilize the synergistic effects of different components. The photovoltaic devices fabricated with NiTa2O6/HBC, MnTa2O6/HBC, and AlTaO4/HBC counter electrode catalysts demonstrate the brilliant power conversion efficiency (PCE) of 7.09%, 7.39%, and 7.86%, respectively, outperforming the Pt-based cells (6.80%). This work offers a strategy for the further rational design of efficient, inexpensive, and durable electrocatalysts for advanced energy technology applications.  相似文献   
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d -Glucaric acid (GA) is the one of aldaric acids and is an important bio-based building block for polymers. In this study, poly(m-xylylene-acetyl glucaramide) and poly(p-xylylene-acetyl glucaramide) were synthesized from GA acetate and two kind of aromatic diamines by solution polymerization. The chemical structures of the polyamides were analyzed by nuclear magnetic resonance spectroscopy. The weight-average molecular weights ranged from 3.3 × 103 to 1.15 × 104 with a polydispersity of 1.6–1.9, depending on monomer ratio or monomer concentration in solution. The 10% decomposition temperature of the polymers was about 210 °C. Differential scanning calorimetry revealed that the polyamides exhibited no peaks attributed to crystallization or melting point, which indicated that the polyamides were amorphous. No crystalline pattern was observed in the X-ray diffractograms, supporting this result. Polarized optical microscopy observation revealed that the polyamides exhibited melting-like behavior at above 150 °C, which was attributed to glass-transition behavior. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47255.  相似文献   
9.
异己糖醇是一类碳水化合物衍生二元醇,具有高刚性、手性、亲水性和低毒等特性,在制备新型生物基、生物可降解高分子材料方面具有广阔的发展前景。围绕近年来研究较为充分的全脂肪型及半芳香型异己糖醇基均聚酯与共聚酯,综述了其合成、热学性能、力学性能、生物降解性能及潜在应用,探讨此类聚酯的高效聚合反应工艺及构效关系。异己糖醇结构单元的引入可有效提高聚合物的玻璃化转变温度,以及促进其水解和生物降解性能,在构建具有更高性能的环境友好型聚酯方面具有较高潜力,有望应用于工程塑料、纤维、生物医药等领域。此类生物基聚酯的大规模商业化需进一步开发更高效、温和的聚合反应工艺以攻克其热敏感和热降解问题。  相似文献   
10.
回顾分析了国外微藻生物柴油、秸秆乙醇汽油、新一代生物质汽油的新进展和工业化过程面临的挑战及对策。并建议要根据我国生物质原料供应、科研基础,开展国际合作,力争在2015年建成微藻生物柴油、秸秆乙醇汽油、生物质汽油工业示范装置,为以后的大发展奠定基础。  相似文献   
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