MATERIALS DuPont extends Biomax PLA modifier line with FDAcompliant grade
uPont Packaging has expanded its DuPont™ Biomax® Strong family of polymer modifier additives with a grade that is compliant with regulations for food contact applications in the USA and Europe. Launched last year [ADPO, October 2006], Biomax Strong additives improve the performance of renewably sourced bio-based polylactic acid (PLA) packaging.
New Biomax Strong 120 toughens PLA packaging materials while maintaining compliance with the food contact requirements of the US Food and Drug Administration (FDA) and similar regulations in Europe. Like its predecessor Biomax Strong 100, which is designed for non-food packaging applications, the new Biomax additive overcomes the natural brittleness of PLA food packaging, providing improved impact strength, flexibility and melt stability with minimal reduction in package clarity, DuPont says. ‘Offering a food contact compliant grade of Biomax Strong gives DuPont a way to help food marketers take better advantage of an environmentally preferred solution in packages such as clamshells used in fresh produce sections,’ says Shanna Moore, global market manager for DuPont Packaging. The company is firmly committed to developing sustainable solutions, including solutions that improve the performance of other sustainable offerings in the market, Moore adds: ‘By improving the performance of bio-based and biodegradable products, Biomax Strong can help the packaging industry deliver high performance at a competitive price.’ The Biomax Strong additives are petrochemical in origin but, when used at recommended addition levels, the modified material will comply with international composting requirements, the company says. • Researchers at a number of other institutions are also focusing on reducing the brittleness and improving the melt strength of PLA biopolymers, as several presentations at the May ANTEC conference in Cincinnati revealed. Specialty Minerals (www.mineralstech.com) has been working on the use of specially engineered, high
Additives for Polymers
aspect ratio, calcium carbonate-based reinforcements to overcome PLA’s brittleness. Its mineral-EMforce Bio additive has been shown to improve the modulus and impact toughness when used in loadings of 20–30%, PRW.com reports. Arkema (www.arkema.com) reported that its Biostrength 700 additive product can almost double the melt strength of PLA, while Biostrength 150 substantially improves impact performance, although it does increase haze levels at the same time. For applications where translucency is important, Biostrength 130 does not substantially increase haze levels, though the impact performance is slightly below that achieved with Biostrength 150. In the USA, researchers at Michigan State University are investigating the use of nanoscale hyperbranched polymers to improve PLA’s balance of stiffness and toughness. The modified material should also provide an ideal matrix for nanoclays, talc and natural fibre reinforcements, the researchers say. And at the Industrial Material Institute in Quebec, a team is looking at reducing the brittleness of blends of PLA with thermoplastic starch. They report that, if such blends are properly plasticized and compatibilized through reactive extrusion, then the starch phase can considerably increase the blend’s ductility. In addition, by grafting maleic anhydride onto PLA prior to blending, they have achieved elongation at break in excess of 200%, compared to 5–20% for unmodified blends and pure PLA. Contact: DuPont Packaging, Barley Mill Plaza 26-2122, Lancaster Pike & Route 141, PO Box 80026, Wilmington, DE 19880-0026, USA. Tel: +1 302 992 5225, Fax: +1 302 992 3495, Web: www.dupont.com
PolyOne launches liquid colorants for clear engineering resins
olyOne Corp has introduced new patent-pending PicoTint™ Liquid Colorants, which are said to be ideal for use with a wide range of clear thermoplastic engineering resins such as polycarbonate, poly(methyl methacrylate), styrene acrylonitrile (SAN), clear acrylonitrile butadiene styrene (ABS), glycolized polyester and terpolymers.
According to John Van Hulle, PolyOne VP and general manager, North American Color, the company drew on its in-depth knowledge of resins and compounding to create a polymer-based carrier for the liquid colorants; conventional liquid colorants use oil- or surfactant-based carriers. As a result of the new technology, PicoTint colorants are heat and light stable, weather well and have an extended shelf life of at least one year, the company claims. The new colorants also have superior pigment and dye dispersion, which resists streaks or swirls. In addition, PicoTint colorants have excellent clarity and do not affect the physical properties of the clear engineering resin at loading levels of up to 0.5%, PolyOne says. According to Van Hulle, the new levels of thermal stability and processability provided by the PicoTint range offer customers the opportunity to use liquid colorants in new applications that would previously have required the use of pre-coloured resins or pelletized colorant masterbatches. Processors and compounders can use PicoTint colorants in extrusion, blow moulding and injection moulding processes in low let-down ratios of 0.25% or less, PolyOne says. In addition, the liquid colorants can be introduced downstream in the manufacturing process, resulting in faster colour changeover. Liquid colorants also require less storage space and reduce inventory cost compared with pre-coloured resins or colour concentrates. PicoTint liquid colorants are said to be ideal in applications where clear, bright colour is needed, including automotive applications such as taillights, turn signals and headlights; durable houseware and applianc e applications; electronics; office applications such as furniture; industrial applications such as thermoforming or extrusion sheets; and point-of-purchase displays. PolyOne has also provided additional information concerning its recently launched OnColor™ BIO Colorants and OnCap™ BIO Additives for use in biodegradable polymers such as polylactic acid (PLA), polyhydroxybutyrate-valerate copolymer (PHBV), polybutylene succinate (PBS), polybutylene adipate-co-terephthalate (PBAT) and starch blends [ADPO, May 2007]. The colorants are available in a wide range of transparent and opaque colours, while the additives product line includes denesting, antistatic, slip, antiblock, UV protection, blue tone and anti-fog additives. The company also offers OnColor Smartbatch™ BIO masterbatches, which combine the BIO colorants and additive
products into a single masterbatch. In addition to offering several standard product grades, PolyOne says it can customize an OnColor BIO Colorant or OnCap BIO Additive to meet a customer’s specific processing need or end-use application. According to the company, the new colorants can be used in extrusion and blow moulding processes and meet several global industry and composting standards, including EN 13432 (European Union), ASTM D6400 (USA), BPS GREENPLA (Japan) and DIN CERTCO (Germany). Contact: PolyOne Corp, 33587 Walker Road, PolyOne Center, Avon Lake, OH 44012, USA. Tel: +1 440 930 1000, Fax: +1 440 930 3064, Web: www.polyone.com
Light-diffusion masterbatches from Ampacet improve LED device efficiency
mpacet has developed a new line of lightdiffusing masterbatches using a polymerbased diffusion compound specially formulated for polycarbonate, acrylic and other clear plastics. According to the company, these masterbatches provide greater light transmission than traditional mineral-based light diffusers, which are used to eliminate the hot spots caused by light-emitting diodes (LEDs) in such applications as signage and illuminated knobs.
Most LED diffusers contain fine particles of a mineral such as calcium carbonate, barium sulphate or titanium dioxide. In addition to scattering light, these minerals absorb a significant amount of light and often reduce the transmission of LED light to 80% or less. Ampacet says its new products – Ampacet 603171-AY for acrylics and its counterpart for polycarbonates Ampacet 603170-PC – contain proprietary spherical polymer particles that scatter and spread light in plastic sheets and films to form an even illumination, while allowing light transmission levels of about 90% or more. For example, a 35-mil (c. 0.9 mm) acrylic sheet containing 3% Ampacet 603171-AY has a light transmittance of 95%. A similar sheet formulated with 3% calcium carbonate has a transmittance of 55%, according to Ampacet. Similarly, 35-mil polycarbonate sheets containing 3%
Additives for Polymers