Acrylate grafted dehydrated castor oil alkyd - A binder for exterior paints

To meet the requirement of improved durability of alkyd resin for use in weatherwork paint for superstructure of ships, an attempt has been made to chemically modify a castor oil alkyd by graft copolymerization with methyl methacrylate and butyl methacrylate in view of their ability to provide polymers with good exterior durability. Characterization of the experimental resins, in respect to physical properties, was carried out using instruments such as a vapor pressure osmometer, rotational viscometer, universal tensile testing instrument (Instrom 1123), and differential scanning calorimeter. Performance of the resins was evaluated using a fluorescent UV accelerated weatherometer and multi-head glossmeter. The results reveal substantial improvement in drying and weather resistance properties of castor oil alkyd on graft copolymerization with both methyl methacrylate and butyl methacrylate. The improvement in these properties is marginally superior in the case of MMA grafted alkyds. MMA modification also enhances the mechanical properties of the grafted castor oil alkyd.