Automotive economy demands drive new polymer developments
Stanyl, a high-performance polyamide46 (PA46) resin from DSM Engineering Plastics, has been chosen for the production of tumble valve bearings for the latest generation of Mercedes BenzV6 and V8 engines.
Tumble valves are an integral part of the manifold, optimising air flow in the combustion chamber. It is the first time that such tumble valves have been produced by assembly moulding and, according to DSM, Stanyl played an important role in making this possible (Fig.1).
With the in-mold assembly technique, components are assembled inside the mould in a two shot (2K) process. This results in significant cost savings compared to traditional processes in terms of assembly, tooling, and machinery.
For in-mould assembly to work, a combination of materials is required which can meet both the in-mold process demands as well as perform reliably under the operating conditions throughout the life of the engine. In the moulding process, says DSM Engineering, Stanyl has outstanding stiffness at high temperatures – even close to its melting point – which enables 2K overmoulding without distortion of the initial moulding. As the assembly has a bearing function, free movement of the two components is required after production. This requires that no adhesion occurs between the two materials during the moulding process and that shrinkage coefficients are such that free movement is maintained after moulding and at engine operating conditions and temperatures up to 150°C. In addition, wear and friction behaviour of the component materials is very important. The tumble valve bearings have to resist high loads that are constantly operating at high frequency when the engine is running. Good wear and friction properties play an important role in the lifetime of the component itself and subsequently the engine. A grade, selected from the Stanyl portfolio of materials that are optimised for stiffness and improved tribological performance, gave the right performance against the mating material in the assembly (PPS).
“The success of this full plastic tumble valve proves the excellence of plastics in reducing costs while providing functionality”, said Thomas Lunow, technical engineering specialist for DSM. “This solution also demonstrates the reliability of Stanyl in such challenging applications”.
Innovation in Frankfurt
Meanwhile at the Frankfurt motor show Sabic Innovative Plastics – formerly GE Plastics – celebrated the unveiling of the OPEL Flextreme and Chevrolet Volt concepts, illustrating lightweight polymer material innovations that complement the E-Flex architecture and showcase energy-saving transparent window glazings and lightweight body panel technologies.
SABIC Innovative Plastics worked with General Motors Europe to adapt leading-edge technologies used in the Volt for the OPEL Flextreme. In line with GM’s strategy to showcase environmentally compatible and consumer-focused mobility, SABIC Innovative Plastics’ eco-responsible materials significantly reduce part weight for better fuel economy while enhancing safety and expanding design freedom.
The plastics company showcased its approach to energy conservation with a display of renewable materials such as: Valox iQ resins for headlamps and connectors; Xenoy iQ resins for body panels; and NextGen Lexan GLX resins with Exatec glazing systems for lightweight glazing.
“Building on our initial relationship with GM on the Volt, we are pleased to continue our collaboration with GM Europe Design in developing the key material concepts behind the Flextreme,” said Gregory A Adams, automotive vice president, SABIC Innovative Plastics. “This exciting, environmentally progressive vehicle demonstrates the benefits of using lightweight, high-performance materials in creative ways.”
Tackling China
Borouge, a leading provider of innovative, value creating plastics solutions, has announced plans to develop a compounding facility in China for the manufacture of high performance polypropylene compounds for applications in the automotive sector.
The new compounding facility will be constructed in the Shanghai area and will have an annual capacity of up to 50000 tonnes with further expansion possibility. It will be strategically located to take advantage of the supply of Borstar polypropylene from its production plant in Ruwais, Abu Dhabi, through an advanced logistics concept and to serve current customers such as VW, GM and PSA in China, future customers in China and other Asian and Middle East markets.
The compounding facility will primarily provide polypropylene solutions for the automotive industry including endurance and high impact interior and exterior applications such as dashboards, door panels and bumpers, as well as mineral filled PP and glass fibre reinforced PP for under the bonnet applications. Value-added compounds for electrical appliances will also initially be part of the manufacturing portfolio.
The new site complements Borouge2, the major expansion of Borouge’s production facilities in Ruwais which will triple its annual capacity to two million tonnes of polyolefins and enable the production for the first time of polypropylene matrix materials. The increased capacity is expected to come on-stream in 2010, in parallel to the start-up of the new polymerisation units in the Borouge2 project. It also complements the development of Borouge and Borealis' network of Innovation Centres focused on customer applications. Borealis is together with the Abu Dhabi National Oil Company (ADNOC) a co-owner of Borouge and already markets its high value polyolefins to the automotive markets in Asia through Borouge.
“This investment represents a very significant step in the ability of Borouge and Borealis to serve its customers in the automotive industry with innovative plastics solutions and to take advantage of this rapidly growing market sector,” commented Harald Hammer, ceo of the Borouge marketing company. “The location in Shanghai puts us close to the high growth markets in Asia, close to our supply channels and close to our customers.”
Functional films
Dutch company Avery Dennison Graphics and Reflective Products Europe is adding a new element to its portfolio of Avery Graphics products: professional-grade self-adhesive surface protection films for automotive exteriors. The new Avery7000 functional films range can be used over printed or computer-cut graphics and vehicle wraps, or as ‘standalone’ protection directly applied to vehicle paintwork.
Says Bill Podojil, sales and marketing manager, automotive, for Avery Dennison Graphics and Reflective Products: “On-the-road damage to cars, vans, and trucks is a major expense for companies running commercial vehicle fleets. It makes sense to protect at least the critical areas of bodywork from stone chipping, surface abrasion, and other external factors. Avery7000 functional films are designed to provide outstanding protection, with the added value of real cost savings for the transport owner.”
The range features a choice of three transparent, extra-durable films: 150micron and 325micron specially-modified vinyls offering a five-year applied life, and a 200micron polyurethane film offering a seven-year applied life. Complementing these core products are the exterior blackout films: 150micron fine-grained and 200micron medium-grained textured, black, specially modified vinyl films for optimal surface protection.
