NatureWorks, PLA

Much has been written about Cargill Dow LLC s polylactide (PLA) polymer, also known as NatureWorks PLA. PLA is a thermoplastic produced from biomass sugars by fermentation. The fermentation product, lactic acid, is converted into a lactide that is purified and polymerized using a special ring-opening process (18). 

In April 2002, Cargill Dow started up its first large-scale PLA plant in Blair, NE. The plant has a capacity of 140,000 metric t, and demand for NatureWorks PLA has been so strong that construction of a second plant is likely to begin within a few years (19). Cargill Dow projects a possible market of 3.6 million metric t by 2020 (20). 

Cargill Dow LLC (2003), "NatureWorks PLA Breaks Tradition in Packaging," press release, February 12, 2003, Website http //www.cargilldow.com. 

The main types of NatureWorks PLA that are available for packaging applications include general purpose film grades, extrusion coating, extrusion and thermoforming grades and injection stretch blow moulding. 

Clear extrusion sheet grades are designed for extrusion and thermoforming applications, and like other NatureWorks PLA polymers, use conventional processing techniques and equipment. Potential uses include dairy containers, food service ware, transparent food containers, blister packs, and cold drink cups. 

Similarly, PLA biodegradable polymer prices have fallen sharply over the last five years since the polymers were first commercialised. NatureWorks PLA is now available at prices between 1.37-2.75 per kg compared to a price range of 3.0-3.5 per kg three years ago. NatureWorks PLA has been price competitive with PET for example over the last twelve months as PLA manufacturing scale has increased and process improvements were made alongside the recent sustained higher levels of PET pricing. 

In the synthetic biodegradables sector, BASF expanded its Ecoflex-brand with Ecovio, a blend of NatureWorks PLA and Ecoflex. 

Major retailers and food manufacturers have opted for biodegradable packaging in 2005. For example, Wal-Mart Stores selected NatureWorks PLA to manufacture containers for herbs and other products, while Del Monte Fresh Produce increased its use of NatureWorks PLA for packaging fruit. 

Ex-Tech Plastics Inc. became the first company to produce thermoformed sheet based on NatureWorks PLA in 2003. 

Wilkinson Industries Inc. became the first US company to manufacture thermoformed food containers and trays made from biodegradable polymers. The NaturesPLAstic product range is based on NatureWorks PLA polymers. 

In 2004, two of the world s leading processors of rigid plastic packaging, Huhtamaki and RPC Group, both announced new product ranges based on NatureWorks PLA. 

Faerch Plast AS is a manufacturer of packaging for the food and retail sectors. It offers a wide variety of plastic types, including articles based on NatureWorks PLA polymers. Target markets include fresh foods such as meat, salad and pasta. 

In 2005, Wal-Mart decided to switch from petroleum-based plastics to corn-based plastics based on NatureWorks PLA. NatureWorks will initially supply PLA for manufacture of 114 million packages a year for fresh strawberries, sprouts, cut fruit and herbs to Wal-Mart. Plastic gift cards, salad boxes, deli trays, tomato packages, plastic film on donut boxes, and other applications will follow. 

Plastic Suppliers Inc., a US extruder of blown film for labels and envelopes, has produced the world s first blown film from NatureWorks PLA. It was hitherto thought that PLA was unsuitable for blown film extrusion. Plastic Supplies claims that its EarthFirst film is 100% compostable, has high gloss, optimum clarity and transparency, high moisture vapour transmission rate, flavour retention, odour barrier, is breathable and is US Food and Drug Administration (FDA) compliant. Areas of application for EarthFirst include window carton film for food packaging, label film, floral wrap film, shrink film and envelope film. 

In 2005, Husky working alongside BIOTA Brands of America, blow moulding equipment supplier SIG Corpoplast and Cargill Dow, which supplied its NatureWorks PLA material, introduced the first biodegradable water bottle onto the US market. Husky supplied BIOTA with the 24-cavity HyPET 120 injection moulding system. 

NatureWorks PLA claims to be the world s first greenhouse-gas-neutral polymer. This factor is important for European customers whereby NatureWorks PLA could assist them to achieve compliance with the greenhouse-gas-emission reduction requirements of the Kyoto Protocol that came into effect in February 2005. 

The greenhouse-gas-neutral claim is the result of the combination of renewable-resource-based feedstock, along with the purchase of renewable energy certificates (RECs) backed by lifecycle assessment data. These RECs will serve as an offset to cover all of the emissions from the energy used for the production of NatureWorks PLA. The company will purchase certificates for projected 2006 production at its 140,000 tonne capacity manufacturing plant and 182,000 tonne capacity lactic acid plant in Blair, Neb., USA, as well as at its corporate offices in Minnetonka, Minn., USA. The purchase of renewable energy will allow NatureWorks to decrease its fossil fuel footprint by 68%. 

NatureWorks says that NatureWorks PLA resin is competitive with petrochemical-based products. The company claims that its PLA has a life cycle that reduces fossil fuel consumption by 50% in its production and emissions of greenhouse gases are reduced by 15-60%. Over the next few years, around 250m is to be invested in commercial development and technology improvement. 

NatureWorks currently offers two biodegradable polymer brands for packaging and fibre applications. NatureWorks PLA is used for manufacture of food packaging and serviceware. Ingeo PLA is used for manufacture of nonwoven textile fibres. 

NatureWorks PLA can be extruded, cast or biaxially oriented, and thermoformed using conventional processing equipment. The company claims that NatureWorks PLA performs like traditional petroleum-based plastics, and in some cases offers better performance characteristics, including gloss, clarity, strength, and flavour and aroma barrier. 

In November 2005, BASF announced that it was expanding its Ecoflex-brand natural plastic line with Ecovio, a blend of NatureWorks PLA and Ecoflex, which is polyester-based. Ecovio production began in October 2005 at an undisclosed location in Germany. The first Ecovio LBX 8145 grade contains 45% by weight of PLA that is chemically bound to the Ecoflex. BASF said the first application will be in flexible films used for shopping bags. 

PLA permits manufacture of varied and complex bottle shapes and sizes. Monolayer bottles of NatureWorks PLA can be formed on the same injection moulding/stretch blow moulding equipment used for PET, with no sacrifice in production rate. PET has some properties that PLA does not have and so NatureWorks is targeting applications where it has a competitive edge such as fresh food packaging and products that don t require sophisticated barriers such as water, milk and juice products. 

Husky, a strategic partner in the development, has demonstrated production of NatureWorks PLA preforms on a HyPet 90 moulding system. Amcor is at an advanced stage of development with a PLA bottle project for at least one major European customer. However, pricing remains an issue. The PLA price is a bit on the high side compared with PET and polypropylene at the moment, but as volumes pick up the price gap will narrow. 

In November 2005, Jivita became the most recent water to be bottled in NatureWorks PLA. The brand contains natural extracts, flowers, resins and bark, to create the world s first aromatherapeutic water. The company says that the PLA botde and label are a natural fit and help strengthen the product s all-natural appeal. 

In 2005, SPAR Austria started packaging organic apples, pears and tomatoes in rigid trays sealed with a flow wrap film made from NatureWorks PLA. Research showed that consumers perceive that nature-based packaging enhances the appeal of fresh food, and strongly prefer products packaged in biodegradable plastic containers. 

Other retailers using PLA containers include Auchan and Wal-Mart. Auchan launched NatureWorks PLA rigid containers for salads in April 2005 and reported six months later that sales of its PLA packed salads had grown significantly. Auchan plans to expand NatureWorks PLA to packaging its line of pastries. 

Wal-Mart began using NatureWorks PLA for fresh cut fruit, herbs, strawberries and Brussels sprouts in 2005. It plans to expand use of nature-based packaging for items such as cut vegetables, donut boxes, select tomato packaging and gift cards in due course. 

In 2004, Del Monte Fresh Produce NA introduced NatureWorks PLA containers for fresh cut produce in Wild Oats Markets. Del Monte estimates that 50% of its containers for fresh cut produce will be made from NatureWorks PLA in 2006. 

In the summer of 2005 for example, Alken-Maes Breweries served more than 1.5 million beers in NatureWorks PLA cups at three popular Belgian music festivals. A total of 2,940 kg of compostable cups were recycled at those music festivals, creating 147 kg of compost, and generated a lot of interest in Alken-Maes. 

There are also opportunities for serviceware made from biodegradable polymers through retail outlets. Coop Italia for example, became the first retailer in Europe to offer consumers serviceware from NatureWorks PLA in April 2005. The company reported that sales had since exceeded their expectations. 

Alpha Packaging manufactures NatureWorks PLA bottles on stretch blow-moulding machines. Alpha states that PLA is ideal for oil-based products, as well as products with flavour and aroma attributes. The PLA resin is FDA-approved and suitable for food contact. It is used for dairy, juice and water bottles, as well as trays for deli meats, salads and single-serve meals. 

Arthur Blank introduced CornCard USA, a corn-based plastic card based on NatureWorks PLA as an alternative to traditional petroleum-based plastic cards. CornCard USA is identical to traditional plastic cards in look, feel, and durability while offering the same reliability and functionality. Major national retailers and quick service restaurants are already considering alternatives to traditional petroleum-based plastics. 

The Autobar Disposables Group is a pan-European manufacturer of disposable foodservice products trading under the name Veriplast International. Autobar began its experimentation with NatureWorks PLA in 1997 when it manufactured yoghurt containers for Danone, the major European dairy products producer, for trials in the German market. While the containers were found to be successful, the systems to segregate the compostable materials had not yet been developed at that time. 

At its plant in Mont-de-Marsan, France, Autobar begins the production process by creating 330 micron film sheets from the NatureWorks PLA resin using a standard cast extrusion line. The extruded sheet is then thermoformed. 

By using NatureWorks PLA instead of polypropylene, Autobar was able to reduce the wall thickness of the containers, from 460 microns down to 330 microns. The downgauging allows Autobar to use less material, which helps reduce the production costs, without compromising the quality of the thermoformed container. 

After significant input on the thermoforming of NatureWorks PLA, Autobar was recognised by NatureWorks LLC as one of its development partners. 

Bartling offers a range of products made from NatureWorks PLA such as beer and juice-cups, salad-shakers and ice cups. 

Bi-Ax offers the Evlon line of OPLA film made from NatureWorks PLA for packaging and label applications. 

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