Bioplastics rise to the moulding challenge

In April, German moulder Amper Plastik R. Dittrich revealed it is using Biograde C 7500CL cellulose ester compound from FKuR for the base of a new keyboard, which features 45% renewable material content.

The Fujitsu KBPC PX ECO also contains Arboform, a colourable, biodegradable plastic produced with lignin sourced from waste wood and paper by Tecnaro. The lignin-based plastic has “polystyrene-like” properties and provides the keyboard’s “warm-feel” palm rest.

The keyboard is part of Fujitsu’s “Green IT” programme. Rajat Kakar, vice president of the clients group at Fujitsu Technical Solutions, says it is no more expensive than one made of conventional plastics.

“We are making it easy for users to decide in favour of the environment,” he says.

Amper adds that the company has now replaced 60 tonnes/year of conventional plastics with the two biodegradable materials. ABS is still used for laser-printed key caps and the upper housing, but Fujitsu says it is working on changing all remaining parts, aiming at a keyboard consisting of 100% renewable raw materials.

In April, Nova Institute presented innovation awards to two biodegradable plastic products at its bio-based plastics and composites congress in Hanover. The first prize - biomaterial of the year - went to Propper for its Proganic brand compound of polyhydroxyalkanoate (PHA), carnauba wax and natural mineral filler, which was used to make a watering can.

The can was shown in February at the Ambiente 2010 consumer goods fair in Frankfurt and is now available on the market alongside flowerpots. Propper says it the material could also be used to manufacture disposable cutlery.

Henkel also picked up an award for its use of a new injection moulding optimised polylactic acid (PLA) compound in the ECOmfort version of its Pritt correction roller. The roller will reach the market this year. Henkel says the Pritt ECOmfort is the first correction roller to reach an 89% natural plastic content.

Meanwhile, NatureWorks has announced that its new Ingeo 3801X PLA-based formulation - a combination of 65-75% PLA base and various additives - can be used to produce injection moulded parts with thermal dimensional stability up to 120ºC. The material ensures the impact strength and cycle time requirements of semi-durable products.

In the automotive industry, Bernd Koal, development and planning manager at Volkswagen, spoke about developments with PLA at the March 2010 VDI plastics in automotive engineering conference. PLA provides high flexural modulus, scratch resistance, good contour forming and some blending capabilities, but these features are countered by brittleness, high density, limited heat distortion temperature, long crystallisation time with associated long cycle time, low shrinkage and undetermined long-term properties, says Koal.

Despite the fact PLA can be improved with blending and fibre reinforcement, the automotive industry needs to work further on the material before it can be used in interiors, he said.

Meanwhile, the Fiat central research department (CRF) in Orbassano near Turin, Italy, has been looking at a 15-20% kenaf fibre-reinforced aliphatic polyester-modified PLA developed by Italian masterbatch and compound producer EuroMaster in Prato. Fiat CRF is considering using this Bioter blend for a front seat storage container for its next Croma car.

While such compounds have a density disadvantage over conventional unreinforced thermoplastics, CRF has produced a lighter but stiffer part using gas-assist moulding to hollow out a reinforcing channel around the upper rim of the container.

The Fiat CRF work was presented in a joint paper by Dr Guido Belfiore of EuroMaster and Prof Giovanni Levita of Pisa university at the Third ATA automotive technical association convention on ecologically sustainable and recyclable materials in transport at the end of last year.