PP compound: a drop-in solution for ABS tools

When it comes to product design, the price of raw materials is a factor that no European plastics processors can ignore. Certain components, previously made from ABS, are increasingly being put to the test due to the extremely sharp rise in the price of materials over the past few years. Now there is an interesting, economical alternative: Hostacom® ERC 475 L, a PP compound from LyondellBasell.

In addition to the cost of materials, expenditure on tooling represents a significant share of the costs of components involved in plastic products. When it comes to finding a replacement material for an existing part, companies need to avoid incurring extra expense on new tools, in order to protect their competitive positioning.  Product changes also need to take place quickly, without major complications.

Garden equipment manufacturer Husqvarna were faced with this problem when re-developing their Flymo range of lawnmowers. Newly considered materials were required to display sufficient impact strength and stability of shape if they were to be used for the manufacture of body casings. Problem-free processing with existing tools was also a pre-requisite.

With the newly-developed talc-filled Hostacom®, a PP compound from LyondellBasell, they found a drop-in solution with the same shrinkage as ABS and a good mechanical performance. Using this material also enabled a reduction in cycle times compared to ABS, thanks to a processing temperature that was 20% lower. Improved noise damping and chemical resistance also distinguish this product apart from ABS. As for surface quality (brilliance and scratch resistance) Husqvarna initially had to settle for a compromise, compared to ABS.

Meanwhile the talc-filled PP compound has undergone several development phases. Compared to the first generation, the third-generation product, Hostacom® ERC 475L, has improved significantly in terms of brilliance, surface quality and scratch resistance.

As a replacement material for ABS, Hostacom® ERC is not automatically suitable for all applications, as the Hamburg-based plastics distributor K.D. Feddersen has recognised. The criteria that the component is intended to fulfil must be carefully compared against the properties of the two materials. Compared to ABS, the PP compound scores particularly highly with regard to its feel, noise absorption and chemical resistance. According to the manufacturer, no pre-drying is required with Hostacom®. In comparison to ABS, cycle times can also be shortened.

“Prime examples of suitable applications for this type of PP compound are cases for power tools. High-grade, upmarket tools need to be packaged in cases that have a deep sound when they are closed, unlike cheap plastics”, explains Marc Swatosch, Head of Product Management of Advanced Polyolefins at K.D. Feddersen. “Another challenge that more and more manufacturers of household goods are facing comes from the new household detergents in bright and colourful packaging”, adds Thimo Jöns, Product Specialist Advanced Polyolefins at K.D. Feddersen. “With ABS components, these detergents can attack the surface, leaving them dull and unattractive”. Hostacom® ERC offers significantly higher chemical resistance, clearly enhancing the value of the final product”.

An example application: the Husqvarna Flymo with casing made from talc-enhanced Hostacom®. (Credits: Husqvarna)