HIGH CLARITY LINEAR LOW DENSITY POLYETHYLENES FOR FOOD PACKAGING APPLICATIONS

Abstract

The food packaging market includes many rapidly developing, increasingly demanding film applications. Important characteristics for food packaging are heat seal and hot tack properties, puncture resistance, and low temperature properties. Each type of polyethylene has unique strengths and weaknesses that contribute to the overall property balance and define specific markets in which the polyethylene can effectively compete. In the past two decades, many new polyethylenes have been introduced into packaging markets. These new polyethylenes have provided increasing toughness, allowing film manufacturers to produce films at reduced gauges, while maintaining physical properties. High pressure low density polyethylene (LDPE) continues to be a key player in many food packaging markets, especially those in which high clarity is required. A major disadvantage of LDPE is poor impact and tear strength. For increased impact and tear strength, film extruders have traditionally turned to linear low density polyethylenes (LLDPE) and have been forced to sacrifice clarity. These new high clarity LLDPE's allow film extruders to economically produce products with both toughness and clarity using existing equipment.