Comprehensive studies on the foaming behavior of polypropylene: from microcellular plastics to nanocellular foams

聚丙烯发泡行为的综合研究：从微孔塑料到纳米孔泡沫

• 批准号: 543896-2019
• 负责人: Lee, PatrickChangDong
• 金额: $ 13.32万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=699655
• 关键词: Comprehensive; studies; foaming; behavior; polypropylene

Most commercially available "lightweight" foams are made of commodity plastics, among which polypropylene (PP) is a highly attractive material for foaming as it is inexpensive, easy to process, thermally stable, and mechanically strong. However, the low melt strength of PP presents severe challenges in foaming. Significant advances have been made to enhance the melt strength of PP to produce microcellular foams, but little research has been conducted so far on the foaming under processing conditions that involve a wide range of combinations of nucleating agents and blowing agents. More limited knowledge is available on bubble nucleation in the presence of polymer microstructure (i.e., crystals) during the foaming process. This proposal outlines a comprehensive, systematic study on the foaming behavior of PP-based materials. Unique aspects of the proposed research are: (i) injection of chemical and physical blowing agents as well as their blends to explore the effects of type, loading, and their synergy on foaming; (ii) exploration of various types, sizes, and loadings of mineral nucleating agents and comparison between the performance of mineral and non-mineral type nucleating agents; (iii) visualization of cell nucleation and polymer crystallization during continuous foaming processes to understand the interaction between bubble and crystal nucleation. Canadian plastics product manufacturing industry in 2016 valued at $25.3 billion. Foaming is an effective way to decrease the cost, weight, and environmental impact of plastic products by reducing the amount of raw materials used to make them. Improved fundamental understanding on the foaming process and rigorous studies on various processing conditions thus have tremendous potential to positively impact the rational design of polymeric foaming processes and are expected to provide substantial environmental benefits to Canada. Finally, a good number of highly qualified personnel will be trained during the course of this project. It is greatly anticipated that these trained professionals will eventually bring their proficiency to the Canadian plastic and foam engineering community as well as to academia.

大多数可商购的“轻质”泡沫由商品塑料制成，其中聚丙烯（PP）是用于发泡的高度有吸引力的材料，因为它便宜、易于加工、热稳定且机械强度高。然而，PP的低熔体强度在发泡方面提出了严峻的挑战。在提高聚丙烯熔体强度以生产微孔泡沫方面已经取得了重大进展，但迄今为止对涉及成核剂和发泡剂的广泛组合的加工条件下的发泡进行的研究很少。在聚合物微结构存在下的气泡成核（即，结晶）在发泡过程中。 该提案概述了对PP基材料发泡行为的全面、系统的研究。建议的研究的独特方面是：（i）注入化学和物理发泡剂以及它们的共混物，以探索类型、装载量及其协同作用对发泡的影响;（ii）探索各种类型、尺寸和装载量的矿物成核剂，并比较矿物和非矿物类型成核剂的性能;（iii）在连续发泡过程中观察泡孔成核和聚合物结晶，以了解气泡和晶体成核之间的相互作用。 2016年加拿大塑料制品制造业价值253亿加元。发泡是一种有效的方法，通过减少用于制造塑料产品的原材料的量来降低塑料产品的成本，重量和环境影响。因此，对发泡工艺的基本理解的提高和对各种加工条件的严格研究具有巨大的潜力，对聚合物发泡工艺的合理设计产生积极影响，并有望为加拿大提供实质性的环境效益。最后，在该项目实施过程中，将培训大量高素质人员。我们非常期待这些训练有素的专业人员最终将把他们的熟练程度带到加拿大塑料和泡沫工程界以及学术界。