New Polymers from Plant Oil Derivatives and Styrene-Maleic Anhydride Copolymers

Polymerization of triglycerides is usually carried out by attaching a polymerizable group to the triglyceride [1]. Polymers derived from such monomers have low connectivity and low mechanical properties due to the bulky structure of the monomer. This manifests itself in low fracture toughness of the polymers obtained. In this work we changed our strategy by starting first with a suitably substituted polymer having a reasonable molecular weight and attaching the triglyceride derivative to it. This strategy is bound to provide molecular weights that are higher and provide the entanglement lengths needed for higher fracture toughness.

In this study, styrene maleic anhydride copolymer (SMA2000, Styrene:Maleic Anhydride 2:1) is grafted and/or crosslinked with epoxidized methyl oleate, epoxidized soybean oil, methyl ricinoleate, castor oil and soybean oil diglyceride. Base catalyzed epoxy-anhydride and alcohol-anhydride reactions were carried out by using the anhydride on SMA, the epoxy or secondary alcohol groups on the triglyceride based monomers. The characterizations of the products were done by DMA, TGA and IR spectroscopy. SMA-epoxidized soy oil and SMA-castor oil polymers are crosslinked rigid infusible polymers. SMA-epoxidized soy oil and SMA2000-castor oil showed Tg’s at 70 and 66 ºC respectively. Dynamic moduli of the two polymers were 11.73 and 3.34 Mpa respectively. SMA-epoxidized methyl oleate, SMA-methyl ricinoleate and SMA-soy oil diglyceride polymers were soluble and thermoplastic polymers and were characterized by TGA, GPC, DSC, NMR and IR spectroscopy.

References:
[1]. Rios, L. A., Ph.D. Thesis, Rheinisch-Westfälischen Technischen Hochschule, Aachen, 2003.