Novel coatings based on mixtures of blown soybean oil and acrylate prepolymers

Soybean oil (SBO) is an inexpensive, biorenewable commodity material. It is widely used in alkyd resins for coatings, and its derivatives are used to modify various resins.(1-4) Blown soybean oil (BSBO) is prepared directly a nd economically from SBO. It has been a commercial commodity for decades.(5 -8) In view of the potentially abundant supply of BSBO and its low cost, it is surprising that few published studies have addressed the properties and applications of BSBO as a raw material for coatings. Commercial BSBO, whic h is an oligomer of SBO, might be an attractive starting material for prepa ration of coatings since its viscosity and molecular weight are higher than SBO. One consideration is that BSBO contains hydroperoxide and/or peroxide residues from the blowing process. These residues may be a drawback or an advantage; in this study we try to make use of them. The possibility that t hese (hydro)peroxides could be utilized to generate free radicals and initi ate polymerization of monomers to form coating films was explored. Our appr oach is to blend BSBO with di- and tri(meth)acrylate monomers and prepolyme rs, to cast coating films, and to cure and evaluate the coatings. Dry film properties such as pencil hardness, MEK double rub resistance, adhesion, an d impact resistance, have been evaluated using standard methods.(9) (,10) T he results of this research show that low VOC, high-solids coatings can be made by this approach.