Toughening Polylactide with the Incorporation of Trigylceride Oils

The finite supply of petroleum and the environmental impact of petroleum processing have led to an increased emphasis on the use of annually renewable feedstocks for polymeric raw materials. Polylactide is one of most commonly studied polymers derived from a renewable resource. The brittleness of the polymer is one of the main impediments to its use in many traditional petroleum-based polymer applications. One method of toughening a brittle polymer is to blend it with a rubbery material, creating micron or sub-micron sized rubber particles in the brittle polymer matrix (Figure 1). In this study, all-renewable blends of polylactide and triglyceride oils were prepared with melt blending. A new all-renewable block copolymer was synthesized and used as a compatibilizer for the blends. The tensile toughness of the composite was improved by a factor of ten relative to unmodified polylactide.