Amorphous PHA grades launched as performance additives for PVC and PLA

Metabolix (Cambridge, MA ) has extended PHA technology into the amorphous region. The company is launching a new line of amorphous polyhydroxyalkanoate (PHA) grades to be used as performance additives for PVC and PLA. The new materials are produced at a U.S. pilot plant, which is currently being expanded in order, as Johan van Walsem, Metabolix’s Chief Operating Officer commented, “to support existing customers and open new market development opportunities in our target application spaces.” Metabolix says that it will ramp up production to 600,000 pounds annual nameplate capacity over the course of 2016.
 
Amorphous PHA (a-PHA) is a softer and more rubbery (low glass transition temperature or Tg) version of PHA that offers a fundamentally different performance profile from crystalline forms of PHA.  Metabolix’s a-PHA is produced by fermentation and extracted using a patented solvent recovery process.

The production process has been reviewed by EPA and it recently cleared the Premanufacture Notice (PMN) requirement for new materials placed into commerce. Several certifications are pending on a-PHA as a biobased material and for the full range of biodegradation scenarios enabled when a-PHA is used alone or with other complementary materials. Metabolix plans to seek FDA clearance for a-PHA in food contact applications, which would further expand the range of PHA compositions available for use in food contact materials. Metabolix previously received FDA clearance for use of its semi-crystalline PHA grades in food contact applications.
 
At low loading levels, a-PHA can serve as a process aid and performance modifier for PVC. It increases productivity during processing and enhances mechanical performance, with the potential to also deliver cost savings in PVC material systems. In highly filled composite systems, a-PHA acts as an impact modifier, an efficient fusion promoter, and provides improved wood filler incorporation and dispersion, making it possible for PVC recyclate to replace virgin PVC. Metabolix is working closely with customers on a wide range of applications utilizing a-PHA as a modifier for PVC.  These applications include a floor backing material that utilizes PVC recyclate, a highly-filled vinyl flooring system, wire and cable insulation, roofing membranes, PVC/wood polymer composites and other construction and building materials.

Amorphous PHA also complements the bio-content and compostability profile of the biopolymer PLA while delivering significant improvements in mechanical properties such as increased toughness, strength and ductility. Based on these product advantages, Metabolix is working with customers interested in extending the performance range to expand the market opportunity for PLA biopolymers. Many of these customers are focused on developing a-PHA-modified PLA materials for sustainable, biobased and compostable packaging solutions. In addition to conducting numerous trials for transparent packaging films, Metabolix is working with customers interested in a-PHA-modified PLA for thermoformed transparent clamshells used in food service and consumer packaging as well as a-PHA-modified PLA for non-wovens used in personal care applications.