K 2007Trade press conference
July 3 and 4, 2007 inFrankenthal, Germany
A New Family Member of Styrenic Plastic Commodities
Terluran SP-6: An ABS for extrusion
Presentation byHans-Juergen Renner,
Business Development Styrenic Thermoplastics Europe,
BASF Aktiengesellschaft, Ludwigshafen, Germany
Extrusion is one of the longest established methods of plastics processing. Accordingly, the producers of plastics have to keep pace with the demands that have grown over decades from extruding companies for high-grade polymers. While doing this they also have to produce them so economically that they survive the competitive conditions of a mature market. With its new Terluran® SP-6 BASF has now succeeded in bringing a grade of ABS onto the market that is specially tailored for use in extrusion and nevertheless can still be produced under the highly cost-efficient conditions prevailing in the world-scale ABS production plant in Antwerp. SP here stands for “sheets and profiles”.
Commodity range expanded
A few years ago when BASF separated styrenic plastic specialties from styrenic plastic commodities it slimmed its standard ABS range down to just three types produced under highly efficient conditions in its world-scale ABS plant in Antwerp. These are Terluran® GP-22, GP-35 and HI-10 (HI standing for “High Impact”, that is to say highly impact-resistant, and GP for “General Purpose”). Since then extruding companies have repeatedly employed the HI grade in particular for their applications although, strictly speaking, the material had not been developed for this purpose. The additive blend used is designed for injection moulding, in particular for the manufacture of impact-resistant housings. Even its melt flow index is more aligned to the requirements of injection moulding technology. A slight lowering of the melt flow index as a result of adjustments to the process in Antwerp has not yet convinced the extruding companies.
High-quality and economical: the new ABS for extrusion
The new ABS grade Terluran® SP-6 now meets the needs of the extruders even better. This is a product based on Terluran HI-10 whose formulation was matched in close collaboration with users to the requirements of extrusion technology. The developers took care from the outset that the material would also be matched to the Antwerp production line so that the cost advantages of this plant can be further exploited. Accordingly, Terluran SP-6 also is offered to BASF customers at a highly competitive price. The quality advantages associated with homogeneous production in a world-scale plant are likewise retained in full. The level of quality being aimed at can be seen by the specifications of the material. The melt flow index of Terluran SP-6 is about 5 cm3/10min. The notched impact strength of the polymer in practice attains quite impressive values of about
37 kJ/m2 due to its high butadiene content. The important yellowness index is also just 16 and hence very low. Moreover, the inherent colour of Terluran SP-6, which is low anyway, is largely constant. Specifically for pigmentation the correct colour tone can be easily maintained in this way over many production batches.
Practical tests passed with flying colours
In collaboration with customers BASF has subjected the new material to intensive practical tests in sheet extrusion. After over 20 trials on initial samples Terluran® SP-6 lived up to expectations. Specifically, problems arising when unsuitable grades are used – the formation of striped sheet surfaces or of flow structures in coextrusion, the occurrence of residues in degassing or high power consumption at the upper screw speeds – are not observed or considerably reduced with the new material.
The surface quality of monoextruded sheets is greatly improved, after coextrusion with PMMA no flow structures can be identified and even thermoformed parts present lustrous and flawless surfaces. Finally, the new ABS grade from BASF performs well in conjunction with TPU: the delamination occasionally occurring in coextrusion with other ABS materials was not observed.
Accordingly, through the new ABS BASF is meeting the growing demand for a high-quality and at the same time economical ABS extrusion material which enables customers to survive in a market characterised by intense competition. Following positive assessments by the test customers, initial supply contracts have already been agreed.
Photo: BASF, 2007
BASF has added a new standard ABS brand to its slimmed-down product range. Terluran® SP-6 specially devised for extrusion now supplements the three injection moulding grades Terluran GP-22, GP-35 and HI-10. The new Terluran can be produced with great cost efficiency and in very high quality in BASF’s world-scale ABS plant in Antwerp. It is equally well suited for monoextrusion of sheets, for coextrusion with PMMA or TPU and for profile extrusion.