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

Case Western Reserve University, Cleveland OH

Investigators

Abstract

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.