Improvement of melt strength and crystallization kinetics of biopolyesters by reactive extrusion

通过反应挤出提高生物聚酯的熔体强度和结晶动力学

• 批准号: 469482-2014
• 负责人: Kontopoulou, Marianna
• 金额: $ 1.93万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=577409
• 关键词: Improvement; melt; strength; crystallization; kinetics

Bioplastics include thermoplastic polymers that are compostable and/or made from renewable resources, such as poly(lactic acid) (PLA), poly-3-(hydroxyalkanoates) (PHAs), and starch-based materials. The production of bioplastics has seen explosive growth driven by environmental concerns, waste disposal challenges and problems with the supply of petroleum products. Among the key challenges associated with more wide-spread acceptance of bioplastics in engineering applications are their high production costs, brittle nature, slow crystallization rates and low melt strength, which restrict their processability under common polymer processing operations. Their relatively poor engineering properties have limited their applications to relatively low-value, consumer goods. Upgrading the properties of biopolymers to match their performance to that of petroleum-based polymers is therefore an extremely active area of research. The present research project will implement simple blending and solvent-free reactive modification processes to improve the crystallization rates, processability and properties of biopolyester compounds, containing PLA and PHAs. Our preliminary investigations on a small scale have revealed that this approach can result in significant improvements in the crystallization behaviour and melt strength of PLA. The proposed project, supported by E.I. du Pont Canada, aims to optimize and develop these processes on a larger scale, to characterize the resulting products and to further seek applications in commercial processes and products. Specific objectives include the production of sufficient amounts of PHA suitable for use in large-scale compounding; the optimization of the type and amount of peroxide initiator and coagents and the identification of appropriate processing conditions; scale-up of the process to produce sufficient quantities for full property characterization; and comparison with appropriate benchmark materials. The expected outcome is the development of an economically viable, solvent-free, environmentally friendly process to obtain fully bio-based products, with good engineering properties. Funding is requested for a Master's student, and partial support for a PDF and a research assistant.

生物塑料包括可堆肥和/或由可再生资源制成的热塑性聚合物，如聚乳酸(PLA)、聚-3-羟基烷酸酯(PHAs)和淀粉基材料。在环境问题、废物处理挑战和石油产品供应问题的推动下，生物塑料的生产出现了爆炸性增长。生物塑料在工程应用中得到更广泛的接受所面临的关键挑战包括生产成本高、脆性、结晶速度慢和熔体强度低，这些限制了它们在普通聚合物加工操作下的加工性。它们相对较差的工程性能限制了它们的应用，仅限于相对低价值的消费品。因此，提高生物聚合物的性能，使其性能与石油聚合物的性能相匹配，是一个极其活跃的研究领域。本研究项目将实施简单的共混和无溶剂反应改性工艺，以提高含有聚乳酸和聚酰胺的生物聚酯化合物的结晶速度、加工性能和性能。我们的小规模初步研究表明，这种方法可以显著改善聚乳酸的结晶行为和熔体强度。拟议的项目由E.I.杜邦加拿大公司支持，目的是在更大范围内优化和开发这些工艺，表征所产生的产品，并进一步寻求在商业工艺和产品中的应用。具体目标包括生产适合大规模复合使用的足够量的PHA；优化过氧化氢引发剂和助剂的类型和数量并确定适当的加工条件；扩大工艺规模以生产足够数量的PHA以进行充分的性能表征；以及与适当的基准材料进行比较。预期的结果是开发一种经济上可行的、无溶剂的、环境友好的工艺，以获得完全基于生物的产品，具有良好的工程性能。申请资助硕士研究生，部分资助PDF和研究助理。