In the world of automobile design and innovation, material suppliers are often overlooked. The honors and admiration for brilliantly designed and manufactured vehicles are rightly bestowed upon the automobile designers and brands. However, material suppliers play a vital role in helping to bring to fruition the ideas and design innovations automobile companies create. After all, the best designs are futile efforts if there is not a material available that can enable their creation.
Embracing the important role of material suppliers for the realization of automotive design excellence, Volkswagen (VW), and its component supplier, Sole SpA, collaborated with Styrolution (Frankfurt am Main, Germany) for the development of the front grill of VW's Golf VII.
Rethinking a classic
The Golf has emerged as an iconic car in VW's overall portfolio. In production since 1974, the car has established itself as a vehicle for every generation. However, as consumers continue to demand lighter-weight, more spacious and higher-end aesthetics for their vehicles, VW revisited some of the materials it employed when it prepared to redesign and launch the seventh edition of the popular car.
One component that was evaluated was the front grill. Since the 1980s, the same materials had been used for this critical exterior component. As such, Sole SpA (Oderzo, Italy) and VW set out to identify a light-weight, cost-effective plastic that could replace previously used materials while enhancing aesthetics, durability and performance. Not only did VW and Sole SpA need a material provider that offered easily processable plastics with the necessary characteristics, they also sought a partner that offered technical support and developmental expertise.
|The Golf VII: styrenic resins employed in front grill|
Styrenics offer innovative opportunities and possibilities for the automobile industry and can be found in the interiors and exteriors of some of the world's most trusted vehicle manufacturers. As such, when Styrolution was presented with VW's challenge, the expert technical team understood the unique concerns and needs of the company, as well as the trends driving the industry forward.
Styrolution leveraged its expertise of automobile application design and specifications, and embarked with VW and Sole SpA on a collaborative innovation process in which all parties cooperated to identify and customize the necessary solutions. It was established early on that any material solution selected must address four critical areas: aesthetics, UV stability, cost-effectiveness and durability. Based on these requirements, the collective team chose three Styrolution specialty materials for the development of the front grill.
Driving value with styrenics
Three different Styrolution products contribute to the high quality and aesthetic appeal of the Golf VII's front grill. The first is Novodur P2MC which was used for the VW logo in the inferior front grill rod (the bottom rod of the grill where the logo is fixed). A best in class material for more than 30 years, this grade belongs to the Novodur acrylonitrile-butadiene-styrene (ABS) product family and features a well-balanced mix of properties for injection molding, including good impact strength, dimensional stability and heat resistance. Additionally, its easy processability and high aesthetics made it an ideal solution for electroplated applications used in vehicle exteriors, such as a logo. Due to the material's intrinsic strength and durability, it easily passed all performance and quality tests.
The plated components of the front grill - the logo and the inferior rod - were developed to be assembled on the front grill in two variations: painted and unpainted. As such, two different materials were used. The material leveraged for the painted version of the front grill was Novodur H702, a specialty ABS grade that met VW's stability requirements for thermally stressed components. The good heat resistant characteristics of this grade, coupled with its good paint adhesion, high impact resistance and stability, made Novodur a preferred material of choice for the application.
Offering cost-saving options due to the elimination of the painting process, the unpainted version of the front grill was constructed from Styrolution's Luran S 778T SPF30, an acrylonitrile-styrene-acrylate (ASA) copolymer. The Luran S product line is a classic in the automobile industry, driving Styrolution to invest in its continued improvement to result in a best in class UV resistant material solution. Offering high surface quality, as well as major advancements in color fastness and optical appearance for pre-colored unpainted exterior applications, this material addressed both the aesthetic and functional requirements of front grill or external rear mirrors around the world.
Guaranteed quality with customized solutions
As a car brand that promises and delivers on quality, it was vital that the new VW Golf VII components remained durable and beautiful throughout the life of the car. Previously used materials for the front grill did not always maintain their color and high gloss after years of sun and weather exposure. As such, during the collaborative innovation process, Styrolution worked with VW to customize the employed plastics to ensure that the brilliant color and gloss remained intact despite outside conditions.
Customization was achieved through the implementation of Styrolution's innovative SPF30 package. The SPF30 package offered enhanced UV-stability to ensure gloss and color retention for considerably longer periods of time when compared to other materials. Additionally the package helps significantly prevent graying and yellowing as a result of exposure to sunlight. Simply put, through the combination of excellent materials and industry-leading UV protection, Styrolution was able to deliver material solutions that provided a more brilliant exterior color obtained through molded plastics parts with high and low gloss effects.
Quality and innovation for the future
The productive partnership between VW and Styrolution did not stop with the launch of the Golf VII. After Luran S SPF30 was introduced to VW in 2011, its purchasing department recommended it for all exterior parts made from ASA given its quality and desirable mix of characteristics. As a result, this material can now be found in VW's unpainted exterior grills, spoilers, window frames, cowl vents, air inlets and complete radiator grills for transporters. Additionally Novodur P2MC has become the trusted standard for all chrome plated applications in VW's exterior and interior components.
As a company with a reputation built on a history of quality and innovative design, it was essential that VW delivered a Golf VII that met and exceeded consumer expectations while realizing benefits in weight-reduction, costs savings and aesthetic appeal. Through partnership with Styrolution, VW not only achieved this ambition but was also able to reinforce its commitment to developing lasting quality vehicles for the road ahead.
Pierre Juan is Vice President of Global Automotive at Styrolution. Editor's note: The author is a PlasticsToday contributor. The opinions expressed are those of the writer.