Fiber-reinforced polypropylene/elastomer composite

A process for making a fiber-reinforced composite, comprising:

• admixing a plurality of discontinuous fibers with an L/D ratio of 30 to 1,500 and a diameter of 1 nm to 0.5 micron of a solid, flexible material into a melt of a propylene polymer including 90 wt % or more of propylene monomeric units based on the weight of the propylene polymer;
• grafting in the presence of an organic peroxide greater than 50 wt % of the plurality of fibers to the propylene polymer to form a first melt mixture;
• admixing the first melt mixture to an amount of a melt of an elastomer exhibiting a glass transition temperature of less than 0° C. to form a second melt mixture;
• and
• cooling the second melt mixture to form the composite,
• wherein the fibers are present in the composite at 10 wt % to 80 wt % based on the total weight of the composite, wherein the propylene polymer is present in the composite at from 30 wt % to 95 wt % based on the total weight of the composite, wherein the elastomer is present in the composite at from 5 wt % to 50 wt % based on the total weight of the composite, wherein greater than 50 wt % of the fibers are dispersed within the propylene polymer based on the total weight of the fibers in the composite.