Don Rosato

Keyword Abstract: rubber replacement, green, bioplastics, TPE, TPU, SBC, TPO, TPV, nylon, Pearlthane ECO TPU, Merquinsa, Pebax Rnew, Arkema, Hytrel RS, DuPont, propanediol, PDO, Grilflex PEBA, EMS-Grivory, OnFlex U, PolyOne

Bioplastics Market Drivers

Bioplastics based on renewable materials have already found extensive use in the packaging sector, but these materials in the future are expected to increasingly emerge in more components in engineered applications. In an effort to move away from petrochemical raw materials, both the Western Europe, North America, and Japan have developed guidelines that accords preferential treatment to products procured by public institutions that are classified as biopreferred, that is that they meet minimum renewable raw material content standards. Japan is also influencing the growth in bioplastics. In 2002 the Japanese government established the challenging goal that by 2020, 20% of plastics used in that country should come from renewable feedstocks, rather than traditional petrochemicals. Furthermore, 'greening' and 'sustainability' have become embedded in the long-term business strategies of major corporations as well small businesses as they deal with the high cost of energy, concerns about the environmental impact of industry, and the conflicting demands for limited natural resources. Industrial experts project that by 2011 demand for biobased durable goods will account for almost 40% of the global bioplastics market, versus 12% today.

Currently TPEs are being targeted for specialty development. The "greening" of plastics is also having an impact as bets are being placed on biobased or "renewable-content" materials. Thermoplastic polyurethane (TPU), nylon 11, and copolyester elastomers are leading this biobased charge in the 6.6 billion pounds (US$9.75 billion) 2008 global TPE market that will grow to 8.5 billion pounds by 2013 (US$15 billion). Volume growth will average 6% per year, with dollar value growth at 7.5% per year. Higher performance/value TPU systems account for roughly 15% of the volume total, with engineering/copolyester materials at 10%. SBCs (styrene block copolymers) at 40%, TPOs (thermoplastic olefinics) at 22%, and TPVs (thermoplastic vulcanizates) at 13% make up the remainder.

Merquinsa's 'Green' TPE Technology

Merquinsa stands out in the global TPE marketplace in the field of 'green' technology with its groundbreaking leadership in the development of renewably sourced thermoplastic polyurethane (TPU) elastomers. With its proprietary technology, Merquinsa has achieved 20% to 90% by weight renewable resource content as measured by ASTM D6866 in its TPU elastomers and adhesives with performance equal to and in some cases superior to conventional fossil hydrocarbon based TPU products.

Founded in 1964, privately held Merquinsa is a global leader in specialty thermoplastic polyurethanes (TPUs). Headquartered in Spain, Merquinsa and its affiliated companies in the USA and Hong serve a global market in 65 countries. The company's TPUs are used across a wide range of adhesives applications and elastomer products manufactured using extrusion, injection molding, compounding, and calendaring process technology. Rounding out the product range are water-based polyurethane dispersions and prepolymers, for adhesive and coating uses. With a specialty in the manufacture of polycaprolactone based TPUs, the company is the largest consumer of e-caprolactone in the world. Using proprietary, totally continuous state-of-the-art processes Merquinsa produces one of the widest ranges of thermoplastic polyurethanes, which in addition to polycaprolactone, are also based on adipic polyesters, polyethers and a unique series of co-polymers. More recently it has added elastomers and adhesives TPU product lines made from renewable resources.

'Green' for Merquinsa has become a clear business objective and it has made sustainability a keystone of its environment, health and safety policies. The company set the objective that one-third of their products shipped would be based on renewables within the next 2-4 years. Consistent with its dedication to innovation and environmental responsibility, Merquinsa recently announced the expansion of its Pearlthane ECO TPU product lines manufactured from renewable resources. The company's patent pending ECO TPU elastomers and adhesives based on proprietary Merquinsa technology are the world's first TPU ranges derived from biological/agricultural sources rather than fossil hydrocarbons. A breakthrough in polyurethane green chemistry, Merquinsa's ECO TPU technology provides a sustainable alternative to TPUs based exclusively on fossil fuels, offering green design with even better performance than conventional TPUs. The ECO series (Pearlthane ECO elastomers, Pearlbond ECO adhesives) have renewable content ranges between 40 and 95 weight percent and make use of phenols made from renewable resources including vegetable oils and fatty acids.

Ether-Based Bio TPU Wire & Cable Materials (Source: Merquinsa)

The most recent Pearlthane ECO TPU grades complete the range of Bio TPU for 'Green' injection molding elastomeric applications which the company launched last year. Pearlthane ECO TPU grades have been designed for molding and extrusion where ecologically friendly materials can add value to automotive, electronics, and sport/ leisure applications. The materials have excellent mechanical properties and abrasion resistance, and in certain examples provide even better features than that of standard TPU of equal hardness. The Pearlthane ECO grades complement the also recently launched Pearlbond ECO TPU adhesive grades for high performance reactive hot melts (RHM), 'green' shoe stiffeners, and thermobonding textile tapes/films. At the recent Munich Bioplastics Awards Conference Merquinsa announced the development of the world's first ether-based Bio TPU grades. These new Bio TPU grades will be marketed under the Pearlthane ECO brand with a renewable content up to 60 % according to ASTM D6866, and will offer an alternative to petroleum-based TPU and TPE, with excellent mechanical properties, abrasion, scratch resistance, processability, and recyclability. Initial life cycle analysis suggests that manufacturing Pearlthane ECO creates 40% less global warming emissions. Stated simply, for every 10,000 metric tons of ECO TPU that is produced in place of fossil hydrocarbon-based TPU, up to 20,000 fewer barrels of crude oil are consumed, which is equivalent to the energy required by approximately 1500 houses in Germany.

Arkema's Sustainable Nylon 11 Based Engineering Elastomer

Arkema is committed to establishing lasting competitive/safe activities, supplying innovative products and services that enhance quality of life now and into the future. With this goal in mind, the company has adopted a medium term strategic objective to increase to 10% from the present 5% the share of its sales achieved from renewable raw materials. Products which Arkema and its subsidiaries derive from raw materials of renewable origin (>20% carbon of biobased origin) now carry the Arkema Renewables label, and can be identified by a specific logo.

Arkema S.A.'s Technical Polymers Group a unit of its Performance Products business segment develops and produces specialty polyamides and other technical polymers. Chemical company Arkema S.A. engages globally in the manufacture and sale of chemical products, operating in three coherent and related business segments: Performance Products, Vinyl Products, and Industrial Chemicals. The company has six research centers situated in France, the U.S. and Japan, and holds significant positions in its principal markets. It originally developed specialty polyamide (nylon) Rilsan PA 11 one of the first polymers in existence produced from a 'green' raw material, castor beans, in 1942.

In addition to PVDF resins and functionalized polyolefins, Arkema Technical Polymers (ATP) Group produces specialty polyamides based on caster oil derived Rilsan PA11. Unique in the world, the 100 percent natural based high performance polyamide is produced in a complex series of processes in which the polyamide resin is converted by polycondensation reaction from 11-aminodecanoic acid, a caster oil product derived from the seeds of the castor bean. The exceptional biobased high performance polymer is 100% carbon renewable, emitting 40 percent less CO₂ and consuming 30 percent less fossil energy than non-biobased polyamides. Rilsan PA11 polymers are characterized by an exceptional combination of strength, high barrier to hydrocarbons, chemical resistance, thermal stability, and easy processing. By virtue of its unique resistance to hydrocarbon, heat and impact, it is extensively used in automotive fuel lines, as well as oil/gas and industrial applications.

Pebax Rnew Shell, Strap Band (and Tongue) of the Scarpa Hurricane Ski Boot (Source: Arkema Technical Polymers)

ATP has leveraged its expertise in renewable based Rilsan PA11 to develop two new biobased product lines, biobased thermoplastic elastomers (TPEs) and biobased hot-melt adhesives. Biobased Pebax Rnew polyether block amide is the first in a range of engineering TPEs directly inspired by the chemistry of castor oil derived Rilsan PA11. Pebax Rnew grades with 20-90% renewable content and Shore hardnesses of 25-72 D are suitable for electronic, athletic shoe, and automotive applications. New hot-melt adhesive developed by ATP is Platamid HX 2656 Rnew copolyamide, the first 100% biobased hot-melt adhesive made from vegetable oil feedstock. It is intended for film, webbing, or nonwoven filament use in automotive interiors and other applications. With biobased Pebax Rnew TPE the end result is a product that is even better than traditional, fossil fuel based Pebax elastomer. It is just as light but even more resistant to temperature changes and has increased elasticity at low temperatures. It fulfils a double goal of technical performance and respect for the environment. It replaces fossil-based molecules with molecules from renewable sources has reduced fossil-based material consumption by 29% and CO₂ equivalent emissions by 32%. Pebax Rnew bridges the gap between engineered thermoplastics and rubbers and can be used pure, as an additive or in blends with other polymers or rubbers. It can also be reinforced with various fillers.

Other Emerging Biobased TPEs

The first copolyester TPE with renewable content is in early commercialization from DuPont. The collar of the new Salomon Ghost freerider alpine ski boot constitutes one of the first commercial uses worldwide of DuPont Hytrel RS (renewably-sourced) thermoplastic elastomer. Hytrel RS grades will be made of Cerenol polyols derived from propanediol (PDO) obtained from bacterial fermentation of corn sugar.

Renewably Sourced Hytrel RS (Source: DuPont)

Hytrel RS thermoplastic elastomers bridge the gap between rubber and rigid plastics, and provide all the performance characteristics of traditional Hytrel copolyester elastomer materials, while offering a more environmentally friendly solution than petroleum based products. Containing between 20% and 60% renewably-sourced material, Hytrel RS thermoplastic elastomers are made using Cerenol, a renewably sourced polyol derived from corn. Easily processed by conventional thermoplastic methods like injection molding, blow molding, calendaring, rotational molding, extrusion, and melt casting, Hytrel RS thermoplastic elastomers will find application in hoses and tubing for automotive and industrial uses, boots for CV joints, air bag doors, and energy dampers. Hytrel RS offers comparable performance to standard grades of Hytrel.

EMS-Grivory's expanded Grilflex PEBA line includes bio-based materials with 10% to 100% renewable content. The nylon 12 based materials, based on castor and canola oil, have properties similar to standard Grilflex and are targeted for sporting goods.

Finally, a biobased TPU from PolyOne, called OnFlex U, comes from soybean oils. Renewable content is claimed to be 30-45% and hardness ranges from 65-95 Shore A. Performance is similar to traditional grades for sectors like medical, consumer, and industrial.