11 March 2008
11 March 2008
Large and technically complex parts can now harness the mechanical properties of Celstran long-fibre reinforced thermoplastics (LFRT) from Ticona.
Industrial trials and testing by Ticona and Trexel engineers have validated an advanced screw design for microcellular long-fibre reinforced mouldings, whilst predictive data was developed for Celstran LFRT using an advanced screw design optimized for the MuCell microcellular foam process.
“Virtually warp-free, light-weight parts moulded of Celstran LFRT are now a viable option for OEM designers and injection moulders developing large parts and structural profiles,” said Steven Bassetti, Marketing Manager for Ticona. “The Ticona team, working in conjunction with Trexel, developed extensive data for the Celstran LFRT grades using Polypropylene and Nylon 6 and that will help customers predict the performance of parts made with the MuCell process using the new screw.”
David Bernstein, President of Trexel, said, “The uniquely modified MuCell process, when used with our proprietary screw design, offers Celstran LFRT material users the opportunity to realize tremendous benefits and mechanical property advantages of retained long glass fibres. These include potential weight savings of 10 percent, and a 10 to 20 percent cycle time reduction. In addition, customers can get these benefits along with reduced warpage compared to solid injection moulding and prior iterations of the Mucell process.”
Ticona produces Celstran LFRT grades by pultrusion technology that fully impregnates the long fibres to deliver optimal reinforcement to the plastic matrix. MuCell technology involves the use of precisely metered quantities of atmospheric gases (nitrogen or carbon dioxide) in the thermoplastic conversion processes (primarily injection moulding, but also used selectively with extrusion and blow moulding) to create millions of nearly invisible microcells in the end product. “Ticona ran comparison tests with sample plaques moulded solid and then moulded using the new screw under MuCell conditions,” said Stuart Yelland, Celstran Product Manager for Ticona. “The results showed up to a 10 percent weight reduction in parts that retained the micro-cellular structure, maintained low warpage characteristics, and improved glass fibres length, drop impact and tensile strength.” Trexel and plastic processing machine manufacturer Engel have installed MuCell technology, including a 120mm screw based on Trexel’s new design, on an Engel DUO (2-platen) 1000 ton machine. The machine, available for mould trials using Celstran LFRT, is located at Engel’s new technical centre and training facility in York, Penn.