Injection Moulding PHA -
Injection Moulding PHA - a game changer for marine plastic pollution? MHG’s emergence onto the world stage as the premier manufacturer of PHA biopolymers (polyhydroxyalkanoates) came full circle this spring when Belgium’s Vinçotte International awarded its first ever OK Marine Biodegradable certification to the company. The award is especially judicious in light of the fact that plastic pollution in oceans, lakes and rivers has moved to the forefront as one of the most damaging and challenging environmental problems of our age. The validation is also significant in respect to the ongoing domino effect of legislative bans on plastic bags, microbeads, and polystyrene food service items in cities and states across the U.S. and internationally. Just over a year ago, MHG (Bainbridge, Georgia, USA) was basking in the afterglow of its unique position as the only biopolymer company to be awarded all six Vinçotte OK biodegradable and compost certifications available at that time, as well as U.S. FDA food contact approval. MHG’s merger of Meredian, Inc. and Danimer Scientific into a consolidated entity (Meredian Holdings Group) formalized the company’s plan to position itself as a global provider of bioplastic resins. Since then, the company has received commercial scale production validation from food ingredient provider Tate & Lyle (headquartered in London, UK). In addition to ongoing work with LC Industries (Durham, North Carolina) to produce renewable cutlery for U.S. service personnel, MHG has secured a contract to make biodegradable packaging for one of the world’s largest food and beverage companies, and has others in the works. “Historically the packaging and container world is crowded with many different shaped objects made from petroleum-based resins,” says Paul Pereira executive chairman and CEO of MHG. “More recently the introduction of bioplastic polymers made from Canola oils or any fatty acid vegetable oil has started to take center stage due to the renewable content and in some cases the degradability. This transformation will be a game changer for the world of packaging and waste disposal.” By all accounts, MHG is fully on track to expand production of its Canola based PHA to a broader commercial scale. During the fall 2014 planting season, the company’s second Canola crop was widened to 1,600 hectares (4,000 acres). In early 2015, MHG partnered up with Perry-McCall (Jacksonville, Florida, USA) to build out its AgroCRUSH facility to include a 6,000 tonnes (260,000-bushel) grain storage facility. Harvest time commenced in May 2015. The crop is expected to yield six million pounds of PHA resin. To further accommodate new demand, MHG has acquired over 19,000 m 2 (200,000 square feet) of lab and manufacturing space at its Bainbridge facility. As MHG continues on the journey to expand its mission to the world marketplace, Pereira travels from Asia to Europe and throughout the U.S. to introduce PHA to manufacturers. Due to its heat deflection temperature, UV resistance, excellent mechanical properties, and expedient biodegradability, MHG’s Nodax family of PHA serves as possibly the most viable alternative to both petrochemical plastics and less effective bioplastics. The Achilles heel of many competitive biopolymers, including those produced from cellulose, sugars and MHG’s 2015 Canola harvest commenced in May 2015 in Decatur County, Georgia, USA. 22 bioplastics MAGAZINE [03/15] Vol. 10
Injection Moulding starches, is a lack of heat and moisture tolerance. The polymers can soften when even slightly warmed, become brittle and fail when dried or left in sunlight, or become sticky in high humidity environments. Limp bottle caps, wilting coffee spoons, or toys that crumble into powder just won’t do, no matter how environmentally friendly the products seem. Any biopolymer resin used to make such articles must meet the appropriate temperature and viscosity requirements for mass production, remain durable and reasonably heat resistant while in storage or use, and decompose safely and organically in a short period of time. As a thermoplastic polyester, PHA has a heat deflection range of 125 to 170 o C (about 260 to 340 o F). The high melt temperature offers an attractive and effective solution to the problem, considering that the average temperature in a sealed, parked car is 50 °C, a hot cup of coffee can reach 75 °C, and water boils at 100 °C (212 °F). PHA also offers superior biodegradability over many other commercialized bioplastics because it decomposes aerobically in soil and water, and anaerobically in fresh water, salt water, soil and compost. The fact that it is produced by microbial organisms that feed on the Canola oil is the simple reason PHA degrades so well. The material is synthesized within the organisms as a means of fat storage. As a result, many other microbial organisms see PHA as a kind of Twinkie for bacteria. MHG PHA Compostable Spoons, before and after: MHG PHA biodegrades within three months to a year. By: Laura Mauney The Kidd Group Nodax per se is also highly adaptable to various processes and product requirements. Nodax encompasses a family of PHA polymers where each variation possesses a slightly different mix of monomer units, and can thus be customized for different mechanical properties. Explains MHG’s Chief Science Officer and Nodax inventor Dr. Isao Noda, “Various PHA polyesters are controlled by the proportion of the different building blocks (monomers) used to make the large polymeric molecules. For injection molded articles, the variation of the components gives us the very nice extra design flexibility to manipulate the softness of end products. Sometimes we want hard and tough products, while in other applications we need much more soft and flexible items.” In many ways, PHA functions as a better product than petrochemical plastics. It more effectively preserves food freshness, blocks transfer of many odors and gasses, and is toxin-free. PHA can be used successfully to make biodegradable versions of the single use plastic items notorious for polluting oceans and lakes, including plastic bags, microbeads, six pack holders, bottle caps, and all manner of other disposable goods. Though cleaning up the world’s water bodies will require strategies that go well beyond replacing plastic, the introduction of PHA to our throwaway culture has the potential to significantly deter future damage. www.mhgbio.com bioplastics MAGAZINE [03/15] Vol. 10 23
