화학공학소재연구정보센터
Journal of Applied Polymer Science, Vol.63, No.1, 35-45, 1997
Synthesis of Alkyds Involving Regioselective Lipase-Catalyzed Transesterification in Organic Media
Porcine pancreatic lipase (PPL) is established as an effective biocatalyst for the selective transesterification of triglycerides and diols in organic medium at room temperature yielding primarily 2-monoglyceride mixtures. Molecular modelling simulations of repeating units of alkyd resin incorporating one- and two-monoglycerides show end-to-end distance of 9.76 and 12.82 Angstrom, respectively. The modeling studies on the trimers of these repeating units also reveal more extended configuration for the structures based on two-monoglycerides. A comparative study of alcoholysis by conventional base-catalyzed process and this novel biocatalytic process was carried out with coconut oil triglycerides and a series of diols, followed by polymerization. The rates of transesterification were dependent on the nature of triglyceride, diol, concentration of the enzyme, and temperature. The 1,3 specificity of lipase produced 2-monoglycerides as determined by periodic acid method, resulting in uniform distribution of fatty acids along the alkyd polyester backbone. Comparisons are made between those alkyds prepared by base catalysis and biocatalytic method.