New starch-based bioplastics arrive.* Two new families of starch-based bioplastics are coming to the U.S. market. The one that's available immediately is an extension of the line of products supplied by Cereplast, Inc. This company has been offering 14 grades of compostable resins based on polylactic acid polylactic acid /poly·lac·tic ac·id/ (-lak´tik) a hydrophobic hydroxy acid polymer that is formed into granules and used as a surgical dressing for dental extraction sites. (PLA (Programmable Logic Array) A type of programmable logic chip (PLD) that contained arrays of programmable AND and OR gates. PLAs are no longer used. See PLD.(language, music) Pla - A high-level music programming language, written in SAIL. ) or a thermoplastic starch mixed with some PLA. Now the firm is coming out with Cereplast Hybrid Resins, which are blends of plant starch with conventional polymers. These "hybrids" are not described as biodegradable, but rather as a way for manufacturers to reduce their reliance on oil and gas and increase their use of renewable resources. Because they are made with up to 50% conventional thermoplastics, Hybrids overcome what has been a limitation of most biobased resins to date--limited heat resistance in use and heat stability in processing. PP/starch is very like PP The first Cereplast Hybrid product on the market is Biopropylene CP Bio-PP-50. Chairman and CEO (1) (Chief Executive Officer) The highest individual in command of an organization. Typically the president of the company, the CEO reports to the Chairman of the Board. Frederic Scheer describes it as a patented mixture of polypropylene homopolymer with 50% starch and a blend of plasticizers plasticizers mostly triaryl phosphates, such as tricresyl, triphenyl phosphates, which are poisonous. See also triorthocresyl phosphate. or processing aids. Scheer says the product is made by reactive twin-screw compounding in which a chemical coupling occurs between the starch and PP matrix, which accounts for the material's excellent properties. Biopropylene has higher stiffness. strength, and heat resistance than unfilled PP but also has lower elongation and impact toughness. One notable advantage, says Scheer is Biopropylene's easy printability, unlike standard PP. And unlike most biopolymers, it needs little or no drying. The price of Biopropylene is similar to that of pure PP. though its 16% higher density will raise its cost in use somewhat. "We can offer long-term contracts at a guaranteed price." notes Scheer. He will even consider toll com pounding if the customer can get a better price for PP. Targeting durables Cereplast is aiming this product at durable goods durable goods Goods, such as appliances and automobiles, that have a useful life over a number of periods. Firms that produce durable goods are often subject to wide fluctuations in sales and profits. Also called consumer durables. rather than disposable packaging (though several food packagers reportedly are interested). Scheer says it has aroused considerable interest in the automotive field and is also targeted for housewares and other consumer products, toys, consumer electronics, cell-phone and computer housings, medical products, cosmetics packaging, CD/DVD cases, furniture, and building construction. Biopropylene can be tailored for different uses. It can be formulated with any PP resin and various starches--corn. tapioca, wheat, and/or potaro. Cereplast can vary the blend of starches for both properties and economics, Scheer said. Biopropylene has been tested in sheet extrusion, thermoforming, blow molding, and injection molding, though not yet in blown film. It runs on conventional equipment in similar cycle times, but generally at lower temperatures. Processing requires low-shear screws and temperatures below 200 C (392 F). The resin is opaque and can be colored with standard PP masterbatches or colorants specifically designed for biopolymers by firms like PolyOne, Clariant, and Colormatrix. Though not intended to be compostable, Biopropylene is being tested for biodegradability and compostability. The starch component is expected to break down, leaving small fragments of PP. Scheer notes that the resin has already passed toxicity tests required for composting in the U.S. (ASTM ASTM abbr. American Society for Testing and Materials D6400-04), Canada, and Western Europe. Cereplast is also seeking FDA FDA abbr. Food and Drug Administration FDA, n.pr See Food and Drug Administration. FDA, n.pr the abbreviation for the Food and Drug Administration. approval for food contact. Next year, Cereplast plans to launch Biopropylene grades with 60% and 70% starch, and after that will come Hybrids based on LDPE LDPE abbr. low-density polyethylene and HDPE HDPE abbr. high-density polyethylene . [ILLUSTRATION OMITTED] Formable sheet & pellets A second new family of starch-based materials--this one fully biodegradable and compostable--will be introduced in the first half of next year by DuPont in collaboration with Plantic Technologies of Australia. Since 2003, Plantic has been making thermoformable sheets and injection moldable pellets of thermoplastic starch. Plantic uses high-amylose cornstarch cornstarch, material made by pulverizing the ground, dried residue of corn grains after preparatory soaking and the removal of the embryo and the outer covering. It is used as laundry starch, in sizing paper, in making adhesives, and in cooking. that has been chemically modified by hydroxypropylation to make it behave as a thermoplastic. The starch is mixed with other polymeric and non-polymeric ingredients, plasticizers and processing aids. One product is a water-soluble, sheet used for thermoformed candy trays. Other formulations have water resistance for up to 12 weeks. DuPont will market the formable sheet and molding pellets here under its own Biomax trade name. Initially they will be imported, though DuPont could produce the products itself in the future. DuPont will also explore uses of its modifier (programming) modifier - An operation that alters the state of an object. Modifiers often have names that begin with "set" and corresponding selector functions whose names begin with "get". additives in the starch resins, similar to what it has done with Biomax Strong tougheners for PLA. Carol Casarino, DuPont's technology manager for sustainable materials, says the formable sheet will have "value in use" competitive with OPS Ops (ŏps), in Roman religion, goddess of harvests. She was the wife of Saturn, by whom she bore Jupiter and Juno. At her festivals, the Opiconsivia and the Opalia, held in August and December, respectively, she was worshiped as a goddess of sowing , APET APET Amorphous Polyethylene Terephthalate APET Accident Progression Event Tree APET Algorithms Program Evaluation Tool APET Adaptable Performance Evaluation Testbed APET Australasian Perpetual Equity Trust APET Avionics Post-mission Evaluation Team , and PVC PVC: see polyvinyl chloride. PVC in full polyvinyl chloride Synthetic resin, an organic polymer made by treating vinyl chloride monomers with a peroxide. . She notes that the starch-based resins have the advantage of being inherently antistatic. DuPont is developing processing guidelines. Plantic's datasheets indicate that melt temperatures should be below 200 C and some predrying is generally necessary. According to Plantic, material densities range from 1.35 to 1.62. The formable sheet is fairly rigid (319 to 348 kpsi tensile modulus), but the molding pellets come in both rigid and flexible grades (68 to 661 kpsi modulus). Tensile strength ranges from 913 to 6670 psi, elongation at break from 2% to 135%, Izod impact from 0.56 to 1.46 ft-lb/in., HDT HDT Heat Deflection Temperature (plastics) HDT High Dose Therapy HDT Heatpipe Direct Touch (Xigmatek) HDT Heat Distortion Temperature (plastics) HDT Henry David Thoreau at 66 psi from 92 to 117 F, and Vicat softening point Vicat softening point is the determination of the softening point for materials such as polyethylene, which have no definite melting point. It is taken as the temperature at which the specimen is penetrated to a depth of 1 mm by a flat-ended needle with a 1 sq. from 104 to 158 F. The sheet has 60[degrees] gloss of 80 to 85 and transparency of 89% to 93%. NEED TO KNOW MORE? For more information on these companies and their products, visit www.ptontine.com/suppliers Cereplast, Inc., Hawthorne, Calif. (310) 676-5000 * www.cereplast.com Ciariant Masterbatches, Holden, Mass. (800) 782-7333 * www.clariant.masterbatches.com Colormatrix Corp., Berea, Ohio (216) 622-0100 * www.colormatrix.com (800) 438-7225* www.dupont.com PlanticTechnologies Ltd., Altona, Victoria, Australia +61 (3) 9353 7900 * www.plantic.com.au PolyOne Corp., Avon Lake, Ohio Avon Lake is a city in Lorain County, Ohio, United States. The population was 18,145 at the 2000 census. Geography Avon Lake is located at (41.501595, -82.006309). (440) 930-1000 * www.polyone.com LEARN MORE Online Visit www.ptonline.com/articles/200711cu2.html for a link to these related articles. * Extruding Biopolymers: Packaging Reaps Cost Benefit of Going 'Green,' Feb. '07 * Higher Performing Biopolymers Seek New Market Opportunities, Apr. '05 * Online Exclusive: The Global Market for Biodegradable Polymers CEREPLAST BIOPROPYLENE VS. PP HOMOPOLYMER Property CP-Bio-PP-50 Homo PP Density, g/cc 1.04 0.9 Ult. Tens. Str., psi 2410 1650 Ultimate Elong., % 9.5 130.1 Flex. Modulus, psi 139,940 101,718 Tensile Mod.,psi 299,280 119,480 Notched Izod Impact, ft-lb/in. 0.57 1.81 HDT @ 264 psi, F 142.3 129.9 MFI @ 190 C/2.16 kg,g/10 min 3 to 6 3 |
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