PP-TD20 in Automotive Interiors: Door Panels, Pillars and Instrument Panels

Division of labour by location

Large thin-wall parts such as door panel substrates, pillar trims and console bodies are governed by stiffness and dimensional stability, so PP-TD20 is standard.

Areas touched directly — upper door trim, centre armrests — need toughness and switch to PP+EPDM-T20, trading stiffness for feel and low-temperature impact.

Panels that must survive airbag deployment need higher elongation and use dedicated impact-modified systems.

Three hard requirements

One, odour and VOC: odour grade per VDA 270 is typically ≤3.0, with VDA 278 limits on TVOC and fogging.

Two, scratch resistance: interior surfaces are touched constantly, usually requiring ΔL ≤1.5 by Erichsen or five-finger scratch testing. This correlates directly with talc hardness — softer, higher-purity talc performs better.

Three, long-term heat ageing: appearance and property retention after 400 hours at 120 °C, critical to preventing summer deformation and chalking.

Cost and lightweighting

Against ABS, PP-TD20 offers lower density and lower unit price, making it the main cost-down route for interiors. Recent work combining thinner walls with micro-cellular foaming has cut a further 10-15% of weight.

Lightweighting must not mean downrating. After wall reduction, stiffness and assembly strength — especially at snap-fits — need re-validation.