Nanotechnology used in additive to keep PLA clear

A new nanotechnology additive on the market is designed to add strength to polylactic acid (PLA) without diminishing clarity, its manufacturer claims.

Rohm and Haas said its new additive, Paraloid BPM-500, broadens the usability of PLA, a bioplastic used in some "green" packaging. Over the past five years packaging suppliers have been introducing various forms of biodegradable materials in response to projections that consumers and recycling regulations will drive demand for environmentally-friendly packaging. Mandates from giant supermarkets forcing suppliers to make the switch are also coming into effect. PLA, a biodegradable plastic resin made from corn, is manufactured by Cargill subsidiary NatureWorks in the US. Rohm and Haas claims that the packaging industry's move toward PLA resin has been hampered by unmodified PLA being somewhat weaker and more brittle than traditional materials. "Previous attempts to strengthen PLA packaging have sacrificed transparency in their efforts," the company stated. The additive uses dispersible nanoparticles that do not scatter light, allowing for the production of PLA packaging material that exhibits less than 10 per cent haze at 5 per cent loading, the company claimed. The visual transparency is maintained even with the stronger impact and tear-resistance achieved with the additive, the company claimed. Paraloid BPM-500 complies with food contact requirements in Europe and with room temperature food contact requirements in the US, the company stated. Rohm and Haas is based in the US.