Properties of Reinforced Propylene/Acid Compounds

A new generation of glass fiber or asbestos filled propylene/acid copolymers is described in which the matrix resin adheres chemically to reinforcing filler. The adhesion results from the incorporation of the functional comonomer and produces enhanced physical properties of the composite even in pigmented parts. Other benefits of the adhesion include reduced wicking and reduced warpage of the molded object, improved surface gloss and reduced loss in physical properties due to glass fiber attrition during the compounding step compared to conventional polypropylene polymers. Compounding techniques for incorporating the glass fibers into the resin are discussed.