GOALI: Understanding for Control of Gas Barrier Properties of Poly(ethylene terephthalate) and Related Polymers

这项GOALI提案(由数学和物理科学局多学科活动办公室共同支持)描述了一项协同合作研究工作，以阐明控制气体通过以聚对苯二甲酸乙二酯(PET)为基础材料的玻璃聚合物的基本结构特征。成本、材料和加工性能的结合使聚对苯二甲酸乙二酯(PET)成为最重要的食品包装树脂之一。近年来，出现了新的要求。PET在制造氧气敏感食品和饮料的热灌装瓶子和容器方面存在缺陷。对于这些名称，需要对PET的气体和热性能进行修改和提高。合作的协同作用基于凯斯西储大学在运输测量和结构表征方面的专业知识和设施、佐治亚理工学院的计算机建模专业知识以及世界上最大的热塑性聚酯生产商KOSA公司的聚酯合成能力。通过共聚反应改变PET的化学结构，通过结晶和取向改变其固相结构。该研究计划包括设计和合成新的PET共聚物，气体传输测量，与分子弛豫过程的关联，以及结构、分子运动以及自由体积的静态和动态方面的计算机建模和模拟。此外，实验研究还讨论了晶化、取向和热定形所获得的固态形态对气体输运的影响，该研究将对理解非晶态、半晶态和取向聚合物结构中玻璃态气体输运的基本机理具有重要意义。它还将对凯斯西储大学和佐治亚理工学院的聚合物教育产生广泛影响。通过与工业伙伴的密切互动，研究生将熟悉工业部门的需求和观点。本科生也将有机会参与研究。由工业协会邀请讲授的聚合物科学课程将使研究生和本科生接触到阻挡层和传输特性的应用问题。还预计，作为该项目的结果，传输性质的实验将被纳入聚合物科学实验室课程。

This GOALI proposal (co-supported by the Office of Multidisciplinary Activities of the Directorate for Mathematical & Physical Sciences) describes a synergistic collaborative research effort to elucidate the fundamental structural characteristics that control gas transport through glassy polymers using poly(ethylene terephthalate) (PET) as the base material. The combination of cost, materials and processing properties has made poly(ethylene terphthalate) (PET) one of the most important food-packaging resins. New requirements have emerged in recent years. PET has shortcomings for making hot-fillable bottles and containers for oxygen sensitive foods and beverages. For these appellations the modification and improvement of gas and thermal properties of PET is required. The synergism of the collaboration is based on expertise and facilities in transport measurements and structural characterization at Case Western Reserve University, the computer modeling expertise at Georgia Institute of Technology, and the polyester synthesis capabilities of KoSa Corporation, the world's largest produce of thermoplastic polyesters. The chemical structure of PET will be modified by copolymerization, and the solid state structure will be modified by crystallization and orientation. The research plan encompasses design and synthesis of new PET copolymers, gas transport measurements, correlation with molecular relaxation processes, and computer modeling and simulation of structure, molecular motions, and static and dynamic aspects of free volume. In addition, the experimental study addresses the effects of solid state morphology obtained upon crystallization, orientation and heat-setting on gas transport.The proposed resrach will have a fundamental impact on understanding the basic mechanisms of gas transport through glassy state in amorphous, semicrystalline and oriented polymeric structures. It will also have a broad impact on polymer education at Case Western Reserve University and Georgia Tech. By interacting closely with the industrial partner, graduate students will become familiar with the needs and perspectives of the industrial sector. Undergraduate students will also have the opportunity to participate in the research. Invited lectures by the industrial co-PI in polymer science courses will expose graduate and undergraduate students to issues in the application of barrier and transport properties. It is also anticipated that as a result of this project, experiments in transport properties will be incorporated into the polymer science laboratory courses.