The material has high UV stability and provides good weather resistance over long-term use. It can be provided in precolored compound to speed up processing. Thermolast K is based on hydrogenated styrenic block copolymers (SEBS). It has good flow, adheres to other materials well, has long-term wear resistance, and comes in a variety of surface finishes.
For the bike carrier, the compound was molded to the polypropylene support arm using two-shot (2K) injection molding technology. Processor of the bracket and fastener sections, Daigler GmbH (Trochtelfingen, Germany), says 2K molding was able to improve the stability of the carrier and also make an attractive optical effect compared to the alternative of inserting clips to hold the bike in place. Kraiburg TPE GmbH, Waldkraiburg, Germany; +49 8638 610; www.kraiburg-tpe.com
RESINS/COMPOUNDS
Food packaging gets all wrapped up
A styrenic copolymer for microwavable food packaging applications, Dylark FG2500, combines low-temperature toughness with high-temperature rigidity for superior freezer-to-microwave performance. It also targets restaurant take-away containers and food serviceware. The material''s toughness reduces the danger of leakage or spillage when hot food is removed from the microwave or brought home in a car, says Debra van Holst, global packaging director at the manufacturer. The FDA-compliant material can be manufactured in pigmented, clear, or foamed containers. It can be processed on existing polystyrene or polyester equipment at faster cycle times and provide enhanced sealability, she says. It also offers good printability and higher material yields. Nova Chemicals Corp., Pittsburgh, PA, USA; +1 412- 490-4292; www.novachemicals.com
New PES grades boast better thermal properties
Gharda Chemicals has unveiled a new sulfone-based resin with rigid segments that possesses a glass-transition temperature of 265-270°C and a continuous usage temperature of 220-230°C. Gafone T-PSS (poly super sulfone) is inherently flame-retardant with a low smoke density and is already used in motor windings. It may also find application in aerospace and automotive wire encapsulation. The current grade commercially available, Gafone T 6300, is amber transparent and positioned as a general-purpose injection and extrusion grade.
Another new product is B-PSS, which is a food contact substitute for polyetherimide (PEI). While it has a glass-transition temperature of 224°C and a continuous-usage temperature of 180°C, its notched impact strength, at 7.1 kJ/m2, is much higher than traditional polyethersulfone (PES). Stress-crack resistance and autoclaving resistance are also higher.
The first application for B-PSS is food containers for Sri Lankan Airlines and EVA Air of Taiwan. The processor is in Belgium and the containers are steam sterilizable. Gharda Chemicals Limited, Panoli, India; + 91-2646-272-386; www.ghardapolymers.com
RESINS/COMPOUNDS
Sweet smell of cellulosics
A recent development uses scented cellulose acetate to snare in prospective consumers. Eastman Chemical worked with three other companies- processor EJ Pack, cellulose acetate supplier Rotuba Extruders and fragrance supplier Eurofragance-to develop "Chocolatine", a thick-walled, injection blowmolded jar made from Eastman''s Glass Polymer copolyester. The jar holds a scented cream with chocolate/vanilla/orange fragrance and the jar''s lid, molded of cellulose acetate, disperses a scent identical to the one of the cream.
Rotuba Extruders Inc. says it partnered with fragrance house Givaudan to develop its own range of scented cellulosics. Rotuba claims to be one of just three suppliers offering cellulose acetate; one uses the material for making sunglasses; the other is Eastman, which has an exclusive deal with Rotuba for the fragranced material.
Cellulosics offer heat and chemical resistance, flexibility, high gloss, transparency and toughness. Givaudan has a library of 33,000 scents, all of which can be integrated into scented cellulosics, says Rotuba. Rotuba claims the scent stays with the acetate cellulose for at least 20 years; scented petroleum-based thermoplastics typically lose their scent after weeks or at most months. Fragrances can be loaded from a low to high concentration and anti-microbial effect as well as an insect repellant quality can be added. Eastman Chemical Company, Kingsport, TN, USA;+1 423-229-2000; www.eastman.com; Rotuba Extruders Inc., Linden, NJ, USA; +1 908-486-1000; www.rotuba.com
ADDITIVES
Plasticizer for sensitive applications targets PVC
Young children tend to discover new things, such as soft toys, by putting them into their mouths. To ensure the safety of flexible PVC toys, the EU issued a regulation, which, starting this year, prohibits the use of certain plasticizers in toys for children under the age of three. A suitable alternative plasticizer for vinyl is found in Hexamoll DINCH, which Heidrun Goth, marketing expert in this manufacturer''s petrochemicals division, says meets all requirements for safety.
"This [product] now allows us to offer toy manufacturers an ideal solution to adapting their products to the requirements of the new EU regulations," Goth says. The plasticizer has low migration and has also found use in many flexible medical devices such as stomach tubes or solution bags.
The plasticizer for PVC and other polar polymers is a 1,2-cyclohexanedicarboxylic acid, diisononyl ester. It is colorless, clear, and is a practically anhydrous liquid with slight odor. It is soluble in organic solvents and miscible with all monomeric plasticizers commonly used in vinyl. It is almost insoluble in water. BASF, Ludwigshafen, Germany; +49 621 6020130; www.basf.com
INDUSTRY NEWS
Coloring technology wins patent grant
Masterbatcher Colour Tone has been granted a UK patent for its coloring technology Vynacol, claimed to be the world''s first such method, allowing easy pigmentation of vinyl similar to that used for other thermoplastics. The patent covers the formulation of the masterbatch, specifically the carrier recipe and the manufacturing technique. Vynacol allows colorant to be introduced without the addition of more additives to rigid PVC.
Traditionally color has been added to rigid PVC by using concentrates such as liquid colors, wax dispersions, universal and flexible PVC-based masterbatches. The problem that occurs is that these systems also can introduce additional components into the compounds that may result in processing problems and lead to application failures such as plasticizer migration or changes in physical properties, says Tony Gaukroger, managing director at Colour Tone Masterbatch.
Universal and polymer specific masterbatches used for adding color to flexible vinyl have been available for many years, he says, but they have never worked reliably in rigid PVC. He says that vinyl is a complex material that is very sensitive to the addition of additives. The company''s Vynacol is said to change all that.
The system is now being used to color packaging, toys, profiles, roofline moldings, bottles, and glazing components. Colour Tone employs the technology to color material it sells as well as it licenses Vynacol to processors who do in-house coloring. Colour Tone Masterbatch, Bedwas, Wales; +44 2920 888910; www.colourtone-masterbatch.co.uk
