Savings for a sunny day

Audi is using recycled plastic bottles to produce corner mouldings for car sunroofs

By Sue Stuckey

Recycled items really are finding their way into new products and technically demanding engineering applications.

Car maker Audi is using recycled plastic bottles to produce mouldings for the front corner pieces of the sunroof on the A6 model. And the new material, DuPont’s Rynite RE4047, is claimed to be superior to virgin resin.

The corner pieces fulfil vital functions in the sliding sunroof mechanism, holding the frame’s aluminium rails together, housing the electrical cable and providing rainwater drain channels.

Made from recycled polythene material reinforced with 30% glass fibre, the mouldings withstand impact from riveting during assembly, and later, the weather and the mechanical effects of prolonged usage.

More than 30,000 open and close test cycles were performed before parts made from the new material met the demanding specifications of Audi, its sunroof maker Webasto, and contract injection moulder Horauf & Kohler.

The UK, Benelux countries, Italy and Switzerland are the biggest collectors of polythene bottles used in recycled materials.