Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/1/2006
Publication Date: 12/1/2006
Citation: Wyatt, V.T., Nunez, A., Foglia, T.A., Marmer, W.N. 2006. Synthesis of hyperbranched poly(glycerol-diacid) oligomers. Journal of the American Oil Chemists' Society. 83(12):1033-1039. Interpretive Summary: Recent legislative energy initiatives have promoted the expanded usage of renewable fuels as a means of decreasing our dependence on imported oil. One such renewable fuel is biodiesel, a diesel fuel alternative that is produced from agricultural fats and oils. With increased production of biodiesel, however, there also is an increased production of glycerol, the major co-product from the process used to produce biodiesel. Accordingly, there is a need to find new uses for glycerol. In this study we demonstrate the potential of using free glycerol to make pre-polymers composed of glycerol units that can be further reacted to produce hyperbranched or dendrimeric type polymers. Such glycerol-based polymers are expected to render new biocompatible polymers that are of interest for potential uses as cosmetics, food additives, surfactants, and lubricants. The development of new markets for glycerol also would have a significant impact on the economics of biodiesel production, since increased credit for this co-product would improve the economics of biodiesel and make it more commercially competitive with petroleum-derived diesel.
Technical Abstract: Novel oligomeric prepolymers were synthesized by acid-catalyzed condensation of glycerol with iminodiacetic, azelaic, or succinic acid. The prepolymers were obtained, on average in 62% yield and were characterized by 13C NMR, 1H NMR, MALDI-TOF mass spectrometry, and GPC. The synthesized oligomers had an average molecular weight of 1543 Daltons (average PD = 1.34, average DOP = 5.5). Hyperbranching was evident in the oligomers produced when using azelaic acid and succinic acid as co-monomers with glycerol, whereas the reaction between iminodiacetic acid and glycerol resulted in linear products bearing cyclic urethane structures.