Purpose

The plastics industry produces over 60 billion pounds of primarily petroleum-based plastics each year. There is a tremendous need for new materials with properties comparable to or better than those of current materials that might be prepared from renewable natural resources.

The Larock group is developing novel polymeric materials ranging from elastomers to tough, hard plastics by the cationic, free radical and thermal copolymerization of natural oils, like soy, corn, tung, and fish oils., and readily available comonomers already used in the plastics industry. These materials have thermal and mechanical properties, including outstanding damping and shape memory properties that petroleum-based plastics do not possess.

The investigators have found they can make excellent rubbers and hard plastics by the cationic copolymerization of 55-80 wgt % soy and conjugated soy oils and dicyclopentadiene (DCP), which is as cheap as soy oil ($.28/lb) and an excellent cross linker.

The researchers have also demonstrated they can make a wide range of excellent composites by the cationic copolymerization of corn, 100% conjugated corn or regular soy oils, plus ST and DVD, using glass fibers as a cheap filler.

They have also been able to use natural clay, organically-modified clay and schist as fillers to prepare nanocomposities. All of the glass fiber composites are hard, tough, dark brown materials exhibiting very promising mechanical properties. And this will be a major emphasis for Phase II.

Phase II Research Plan

Because the soy plastics and fillers are inexpensive, and the fabrication techniques well-established, Larock and Gallagher's composites should be quite affordable and useful in a variety of applications. Because the soy plastics are typical thermoses, possessing excellent damping behavior over broad temperature and frequency ranges, their composites should exhibit good creep and fatigue resistance, which are imperative for structural applications.

Objectives: This project will (1) utilize current free radical polymerization techniques to prepare a wide range of soy/corn composites, (2) determine the physical, mechanical and chemical properties of these composites, and (3) optimize those materials with the most promising and/or unique properties made by either cationic or free radical polymerization.

Since many synthetic plastics, elastomers, and even some fibers are prepared using free radical processes, this method is commercially quite important and can typically be carried out under less rigorous conditions than other chain growth reactions. Importantly initial free radical soy plastics have very good wet ability, especially with natural fibers like linen and wood fibers. Thus, the preparation and characterization of natural fiber-reinforced soy/corn oil composites prepared by free radical chemistry will be a top priority in the second year, since they appear to possess even higher moduli and strength than the cationic soy composites, although more work needs to be done on processing.

Impact

The economic impact of the possible substitution of materials developed from this research for some of the 60 billion lbs.(per year) of synthetic (petroleum-based) polymers with soy and corn composites has the potential to be in the millions of dollars.

With the successful completion of this research, soy/corn plastics can be made at a competitive price to most petroleum-based resins using well established technology. The research team anticipates new, affordable polymer composites with industrially viable properties will find wide utility as structural materials.

The thorough understanding of the relationship between composite and properties gained here will lay a firm foundation for scale-up, production, and application of these new composites. The goal is to convert soy/corn oils into higher value products and open new markets for these abundant, natural oils.