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博文

目前显示的是标签为“Rast Method”的博文

Studies in Molecular Weight Determination of Cottonseed and Melon Seed Oils Based Biopolymers

Read  full  paper  at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53007#.VK9E7snQrzE Author(s)    Ibanga O. Isaac * , Edet W. Nsi Affiliation(s) Department of Chemistry, Akwa Ibom State University, Uyo, Nigeria . ABSTRACT Six grades of biopolymers formulated to have oil content of 40% (M 1 ), 50% (M 2 ), and 60% (M 3 ) melon seed oil (MESO) and 40% (C 1 ), 50% (C 2 ), and 60% (C 3 ) cottonseed oil (COSO) respectively, were prepared with phthalic anhydride, and glycerol using alcoholysis-polycondensation process. The extend of polycondensation was monitored by determining the acid value of aliquots of the reaction mixture at various intervals of time. Molecular weight averages and polydispersity index (PDI) of the finished alkyds were determined by Rast method and end-group analysis. Molecular weight averages and PDI vary with differences in oil length of the alkyds, with samples M 2 and C 2 respectively exhibiting ...