THE USE OF EVOH IN RETORTED FILM APPLICATIONS

摘要

Conventional EVOH has been used successfully in rigid and semi-rigid retorted plastic containers for many years now. However, the use of conventional EVOH in retorted films has not met with the same degree of success. This is because the use of conventional EVOH in retorted films poses unique problems, namely hazing and delamination. These problems are the direct result of the high level of water absorbed by the EVOH during the retort process. This paper discusses the nature of water adsorption in EVOH during retorting, and presents the mechanisms for these hazing and delamination phenomena. In addition, this paper describes how this understanding has led to a new modified EVOH specially designed for retorted film applications. Finally, we also discuss the OTR simulation for rigid retorted containers.