Investigation of Expandable Polymeric Microspheres for Packaging Applications
Abstract
This report describes a 3-year investigation, ended September 2010, of expandable polymeric microspheres, conducted by the Natick Soldier Research, Development and Engineering Center, to determine the feasibility of compounding microspheres into a polyolefin film to produce a high performance ration packaging material with reduced weight and improved thermal insulation. Polymeric microspheres are small, spherically shaped particles which encapsulate an expandable gas. When the microspheres are heated the gas inside expands, and this increase in free volume results in a decrease in density. Polymeric microspheres are used currently in many applications including; lightweight shoe soles, printing inks, internally pressurized tennis balls, and foaming cable compounds. Microspheres were compounded into high density polyethylene (HDPE) and polypropylene (PP) at various loading levels to successfully produce a polymeric microsphere loaded film for the first time. Three processing trials were completed. The first trial investigated blown and cast monolayer HDPE with powdered microspheres, the second investigated blown multilayer HDPE with powdered microspheres, and the third compared blown and cast monolayer and multilayer HDPE and PP produced usung a microsphere masterbatch. It was determined that multilayer blown film processing utilizing the microsphere masterbatch was the most efficient method of producing a polymer film with reduced density and improved thermal insulation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 06, 2012
- Accession Number
- ADA560945
Entities
People
- Christopher Thellen
- Jo Ann Ratto
- Sarah S. Cheney
Organizations
- United States Army Soldier Systems Center