Under the Bonnet

Automotive original equipment manufacturers seek under-the-bonnet material solutions which fulfil extremely tough performance criteria.

Under the Bonnet

Extreme durability. Easy processability. Optimal performance.

Under-the-bonnet (UTB) materials have a tough life. Parts located close to engines must withstand high temperatures and are exposed to a variety of corrosive fluids. Other UTB components must also weather rock salt, dirt and dust. Housings for heating, ventilation, and air conditioning (HVAC) systems are subject to constant shock and vibration at high operating temperatures in addition to being exposed to fuels and lubricants. Battery cases must be extremely durable while maintaining good surface properties.

Automotive original equipment manufacturers (OEMs) seek UTB material solutions which fulfil these extremely tough performance criteria. What is more, achieving cost, fuel and weight efficiencies has become an imperative in our sustainability-driven era. Finally, these material solutions must be available globally.

Providing innovative, high-performance UTB solutions

As conventional UTB materials such as steel and aluminium are gradually being replaced by high-performing plastics, Borealis has led the way, developing a wide portfolio of materials, ranging from our FibremodTM family of engineered short (SGF) and long glass fibre (LGF) compounds for reinforced UTB; to high flow pure base resins, compounds with special fillers, and specific additive packages for standard UTB; and a range of polypropylene (PP) grades for injection moulded battery cases. Borealis is in fact the first company to have developed and commercialised a PP material for air intake manifolds, making it the first to have enabled the switch from polyamide (PA) to PP for this component.

The principle advantages of PP in UTB include:
  • Weight reduction
  • Parts consolidation
  • Cost competitiveness
  • Durability
  • Sound dampening effects
  • Anti-corrosion effects
  • Easy processability
  • Dimensional stability
  • Design flexibility

Tailor-made solutions for UTB segments

The most decisive benefits offered by our material solutions that apply to all UTB segments involve three main aspects.

  • Physical: heat deflection temperature (HDT) to withstand high temperatures
  • Stabilisation: chemical resistance, e.g. against corrosive fluids
  • Sustainability: lightweight components help increase fuel efficiency to better fulfil regulatory environmental standards

For standard UTB applications, solutions vary according to placement (e.g. proximity to engine requiring high heat resistance); transparency requirements (water reservoirs); required level of chemical resistance (brake fluid tanks); level of impact resistance and stiffness (lightning housing, under-body shielding).

Our Fibremod innovations are supporting the automotive value chain in achieving its weight-saving and process cost-saving targets. Our customised glass fibre reinforced PP solutions are at the cutting-edge of innovation, bringing lightweight, extra strength and impact performance to a wide range of applications, including front-end carriers, air intake manifolds, fans and fan shrouds, battery trays and more. They also support more environmentally-considerate production by reducing processing temperatures and energy requirements when replacing alternative solutions such as PA.

Highly integrated and complex housings for HVAC systems must withstand shock and vibrations at operating temperatures of up to 70° C while in continuous service. With temperature peaks of as high as 120° C, parts must remain dimensionally stable for sealing and should resist fuel and lubricants. What is more, odourless, low-emission resins are necessary to prevent unpleasant odours in heated air from seeping into a vehicle's interior.

Our PP grades specifically created for the battery segment and approved for use by major European OEMs feature:
  • Excellent impact-stiffness ratio
  • Very good heat stability due to tailor-made additivation
  • Very good surface appearance due to low stress whitening

Driving sustainability today

Our advanced plastic solutions for the automotive industry help reduce vehicle weight for optimal performance. We continue to provide innovative material solutions such as our Fibremod line of glass fibre-reinforced products to help meet tomorrow's challenges. The expansion of our production and compounding capabilities ensures a reliable – and global – material supply. Local on-ground support is readily available thanks to a worldwide network of dedicated experts.


Engineered for success

Global manufacturers of motor vehicles and appliances require new material solutions to replace existing conventional ones. Such materials must not only meet or exceed current performance and quality levels, but must also be globally available, cost and energy efficient, and help contribute to enhanced sustainability. Our Fibremod™ product family of fibre-based compound polypropylene (PP) innovations supports the automotive and appliance value chain in achieving weight-saving and process cost-saving targets. Replacing engineering plastics and metal parts with energy efficient and lighter weight PP grades leads to improved fuel economy and lower CO2 emissions. Our customised glass fibre reinforced PP solutions are at the cutting edge of innovation, bringing lighter weight, extra strength and impact performance to a wide range of applications. Our innovative grades also support more environmentally-considerate production by reducing processing temperatures and energy requirements when replacing alternative solutions such as polyamide (PA).

Consolidated strengths of Fibremod

In order to help our customers and partners identify, compare and select the right grade for their own needs, Borealis and Borouge have consolidated all its fibre reinforced PP material grades under the single name Fibremod. For the most part, Fibremod materials are designed for the higher performance demands of automotive and appliance applications. They provide the complete spectrum of mechanical and chemical resistant property combinations to offer the widest range of solution possibilities. This delivers time and cost savings through greater processing efficiency, parts integration and end-use performance, as well as reductions in part application weight as well as energy and material consumption.

Fibremod benefits at a glance

Short glass fibre reinforced polypropylene (PP-SGF) products are produced as compounds on co-rotating twin screw extruders. The combination of specially sized short glass fibres, the PP matrix and the chemical coupling define the final material properties. PP-SGF products are usually converted to parts using various injection moulding technologies, including complex processes such as injection compression moulding or injection foam moulding.

  • Broad portfolio, from 10%-40% filled standard grades to tailor-made products with optimised matrices, glass fibres and/or filler mixture contents for the most demanding of applications
  • Global availability and production flexibility
  • Wide range of achievable performance attributes thanks to flexibility in selection of base polymers
  • Wide conversion window
  • Less sensitive to welding line, enabling greater design freedom
  • Good surface properties
  • Good organoleptic properties

Long glass fibre reinforced polypropylene (PP-LGF) is a group of glass fibre reinforced products which are produced by pultrusion to achieve increased fibre length in both pellets and final parts. The glass fibres are typically arranged in a parallel manner in the pellets, with each having the same length as the pellet itself.

  • Broad range of fibre and matrix combinations covering glass fibre contents from 20%-60%
  • Highest stiffness and strength at elevated temperatures thanks to tailor-made solutions
  • Proprietary technology enables high fibre impregnation
  • Excellent flowability for smooth processing and uniform shrinkage behaviour
  • Outstanding energy absorption in high-speed deformation
  • Ideal for applications requiring increased impact, temperature and fatigue resistance while maintaining high stiffness
  • Low shrinkage anisotropy (warping)

Reliable global partner in product innovation

Borealis has extensive experience in developing balanced PP-SGF recipes to meet customer demands. We use the best production technology available for optimal product performance and to support customers in material conversion.

We have over 20 years experience in producing PP-LGF and have developed a proprietary processing technology which produces high-quality products in terms of fibre impregnation, and a broad range of fibre and matrix combinations for tailor-made solutions. 

We offer our customers flexibility in production around the world: PP-SGF is produced at Borealis and Borouge plants in Monza (Italy), Beringen (Belgium), Itatiba (Brazil), Shanghai (China), and in North America via toll compounding. PP-LGF is produced both in Monza as well as by way of toll compounding.

Because glass fibre reinforced PP grades are by nature complex in structure, extensive engineering is required. Computer-aided methods reliably predict the final part qualities of the conversion processes (shrinkage, warping etc.), as well as the fibre orientation distribution. Based on these results, our Integrative Simulation Approach computes on a local scale the material behaviour as the basis for simulating performance of the final application. We have established the latest testing standards for glass fibre reinforced PP grades and are committed to further enhancing application performance prediction methodologies.