Heat-shrinkable Polymer Research Articles

Heat-shrinkable polymer blends based on grafted low-density polyethylene and polyurethane elastomer. Part I

Blends prepared by melt-mixing of thermoplastic material-elastomer have gained considerable attention in recent years. Heat-shrinkability of polymer, which is dependent on elastic memory, can be introduced into the system in the form of an elastomeric phase. The present study deals with the measurement of the heat-shrinkability of the blend of grafted polyethylene and polyurethane elastomer. Interchain crosslinking between grafted polyethylene and elastomer improves shrinkability. High-temperature performance of the sample depends on the degree of interchain crosslinking. Probable interactions between the rubber and plastic phase are confirmed by IR spectroscopy. Extraction of the elastomeric phase is restricted due to interchain crosslinking as confirmed by SEM study. © 2000 Society of Chemical Industry

Use of Heat-shrinkable Plastic Film to Extend Shelf Life of ‘Russet Burbank’ Potatoes

Abstract Freshly harvested ‘Russet Burbank’ potatoes (Solanum tuberosum L.) were individually wrapped in heat-shrinkable polymer film and stored for 12 weeks at 8C, 24C, and room temperature (RT), which ranged from 22 to 25C. Film-wrapped potatoes in Cryovac D 950, Cryovac D 955, and Dupont EHC 75 stored at 24C or RT lost less fresh weight than the nonwrapped controls. Wrapped potatoes lost 5% to 7% of their initial fresh weight when stored at RT for 12 weeks, compared to 26% for nonwrapped potatoes. Potatoes wrapped in Cryovac D 955 and stored at RT lost less ascorbic acid and starch and accumulated smaller amounts of total sugars. Lack of major change in the physical, chemical, or physiological characteristics of individually shrink-wrapped potatoes stored at warm temperatures, especially when compared to the nonwrapped controls, suggests that this is a suitable packaging technique for maintaining potato quality.