New dialkyl peroxide for improved controlled rheology polypropylene used in FDA applications

摘要

The use of polypropylene for food contact applications such as specialty packaging films has increased dramatically over the last decade. Much of the polypropylene resin used in this industry has rheology characteristics imparted by a reaction extrusion process. The modification of low melt flow resins is accomplished by an extrusion reaction of the polymer with an organic peroxide. The decomposition of the organic peroxide yields a radical species which modifies the molecular weight profile of the resin. The decomposition of the organic peroxide is known to lead to the formation secondary products (organoleptics) such as alcohols and ketones, which can impart disagreeable odor and taste characteristics to the resin. The US Food and Drug Administration (FDA) regulates the allowable concentration of potentially hazardous materials in food grade applications. The formation of hazardous decomposition products can be eliminated by employing an organic peroxide that does not yield regulated decomposition products. This paper reports the use of a new dialkyl organic peroxide in controlled rheology processes. The new peroxide combines improved odor and taste characteristics with ease of processing and cost advantages.