Materials New Compounds
Materials New Compounds Open More Uses for PLA Samples of Terraloy BP-34001 PLA with enhanced thermal properties (bottom sample in photo) and standard PLA (top sample). At 140 ºC. Standard PLA exhibits considerable heat distortion while sample from Terraloy compound is largely unaffected. Teknor Apex Company from Pawtucket, Rhode Island, USA have reported in early May of this year that new technology developed by the company has eliminated a property tradeoff that until now has limited use of PLA in injection molded semi-durable and durable applications requiring impact strength and heat stability, as well as in high-end disposable food service items such as cutlery, coffee lids, and containers for microwavable products, it was announced today by the company’s Bioplastics Division. Compounding innovations by Teknor Apex have overcome an inverse relationship between heat distortion temperature (HDT) and Izod impact strength in PLA, creating a new series of compounds, Terraloy BP-34001, that provide up to two times the HDT and up to six times the impact strength of standard PLA resins. Previous work to enhance PLA performance beyond standard levels had generated resins with either higher HDT or greater impact strength— but not both in the same grade In comparison with previous enhanced-performance PLA resins, the new Terraloy compounds also exhibit 28 to 30% shorter cycle times in injection molding and incorporate 10 to 30% more renewable resource-based content. Nearly all of the new Terraloy compounds comply with FDA requirements for food-contact applications. “Terraloy BP-34001 Series compounds dramatically improve the heat and impact resistance of PLA while largely retaining the environmental benefit of this polymer as a bioplastic,” said Edwin Tam, manager of new strategic initiatives. “These innovative formulations promise to expand the applicability of PLA, making possible new uses in higher-heat food service items as well as consumer goods.” In property tests, a typical grade in the new series, Terraloy BP-34001D, exhibits a heat distortion temperature (HDT-B @ 0.45 MPa or 66 psi) of 112 ºC and Izod impact strength of 135 J/m. By comparison, approximate values for standard PLA are 65 ºC and 33 J/m. The new compound complies with FDA 21 CFR requirements and has a renewable content of 78%. The base polymers for Terraloy BP-34001 products are Ingeo TM PLA resins supplied by NatureWorks LLC, noted Gregory J. Anderson, Teknor Apex technical manager. “Teknor Apex built upon research by NatureWorks to develop higher-performance PLA compounds,” Anderson said. “By discovering alternative formulations and compounding techniques, we succeeded in eliminating a chronic property tradeoff between heat resistance and impact resistance, while improving processability and reducing the petrochemical content,” Anderson said. MT www.teknorapex.com 16 bioplastics MAGAZINE [03/11] Vol. 6
ioplastics MAGAZINE [03/11] Vol. 6 17
