PP modified compounds, either with mineral fillers or glass fibers find several applications in the automotive sector. Modified PP compounds weigh more due to higher density attributed to the high dosage of heavy fillers required to achieve an improvement in mechanical properties. These products generally are heavier than water and have densities ranging from 1.05 to 1.15 depending upon the filler loading.

Nanoclays, introduced a few years ago, can now be incorporated in either PP homopolymer or impact copolymer at much lower levels as compared to conventional fillers to achieve similar mechanical properties. These nanocomposites of PP have much lower densities and therefore save weight. The lower weight part in an automobile certainly provides better fuel efficiency and is therefore more desirable.

These new grades available at the density of 0.928 gm/cc, offer superior mechanical properties as well as excellent surface finish. This PP nanocomposite is called Forte and was launched in late 2003 by specialty compounder Noble Polymers of Grand Rapids, a division of injection moulder Cascade Engineering after two years of joint development work with Cascade. Working with Honda for their Acura, Cascade found that the originally specified glass-filled PP was causing processing problems, visual defects and warping. Forte was developed as a replacement. In testing by Noble, Cascade, and Acura TL 2004 model, Forte improved the strength and reduced the weight and cost of parts. Further recyclability from Forte would be easier because of much lower level of nano clay that is incorporated in it.

Forte grade with 6% nano clay is making its commercial debut in the structural seat back of Acura 2004 TL passenger cars as a replacement of 30% glass filled PP. It is expected that about 3-4 KT of PP nanocomposite would be consumed for this automotive application in 2004.