A new method for the styrenation of triglyceride oils-namely, sunflower seed oil, tobacco seed oil, poppy seed oil, and linseed oil-is described. This method is based on the incorporation of thermolabile azo groups to the partial glycerides by the condensation of 4,4'-azobis(4-cyanopentanoyl chloride) with the corresponding glycerides. The resulting intermediates were styrenated using a no-catalyzed process by heating at 70-degrees-C. The properties of the styrenated products have been determined and compared with those obtained by classical solvent and mass methods. Moreover, the effect of addition of allyl diethyl malonate, during styrenation, as a degradative transfer agent on the properties of the products, has been studied.