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Novel, partially bio-based poly(vinyl ether) copolymers derived from soybean oil and cyclohexyl vinyl ether (CHVE) were produced by cationic polymerization and investigated for application as alkyd-type surface coatings. Three different polymers were produced and cured clear coatings and free films characterized as a function of CHVE comonomer content and curing conditions. CHVE comonomer content was varied at 0, 25, and 50 wt%, and the three different curing conditions were 1 week at room temperature, 120°C for 1 h, and 150°C for 1 h. The results of the study showed that the thermal, mechanical, and physical properties of the coatings produced from these novel polymers varied considerably as a function of polymer composition and cure temperature. Overall, the results suggest a good potential for these novel copolymers to be used for coatings cured by autoxidation. Compared to conventional alkyd resins, which are produced by high temperature melt condensation polymerization, these poly(vinyl ether)s provide several advantages. These advantages include milder, more energy efficient polymer synthesis, elimination of issues associated with gelation during polymer synthesis, production of polymers with well-defined composition and relatively narrow molecular weight distribution, and elimination of film formation and physical property issues associated with entrained monomers, dimers, trimers, etc.

Prior to the ample supply of low cost petrochemicals, plant oils were used extensively as binders for paints and coatings. The utility of plant oil triglycerides as coating binders stems from the unsaturated fatty acid esters that provide a means to crosslink the liquid plant oil into an insoluble film by simply exposing the thin film of oil to the atmosphere. The crosslinking mechanism is a complex free-radical process, referred to as autoxidation, and involves abstraction of bis-allylic hydrogen atoms by singlet oxygen present in the atmosphere [1-4]. Since the concentration of bis-allylic hydrogens is critical to the autoxidation process, only plant oils with relatively high levels of linoleic and linolenic fatty acid esters are useful, such as linseed, tung, poppy seed and walnut oil. Plant oils such as these are referred to as ‘drying oils.’ Soybean oil (SBO), which is the plant oil currently produced in the highest volume in North America, is referred to as ‘semidrying’ since it is capable of autoxidising to a cured film, but the time required to do so is too long to be useful for paints and coatings. Corresponding author: Dr Bret J. Chisholm NDSU Center for Nanoscale Science and Engineering bret.chisholm@ndsu.edu An alternative to alkyds

Novel bio-based poly(vinyl ether) copolymers derived from soybean oil and menthol were produced by cationic polymerization and investigated for application as alkyd-type surface coatings. Compared to conventional alkyd resins, which are produced by high temperature melt condensation polymerization, the bio-based poly(vinyl ether)s were thought to provide several advantages. These advantages include milder, more energy efficient polymer synthesis, elimination of issues associated with gelation during polymer synthesis, production of polymers with well-defined composition and relatively narrow molecular weight distribution, and elimination of film formation and physical property issues associated with entrained monomers, dimers, trimers, etc. As expected, incorporation of the tri-substituted cycloaliphatic groups derived from menthol pendent to the poly(vinyl ether) polymer backbone significantly increased the glass transition temperature and mechanical properties of crosslinked networks produced by autoxidation. Overall, the results of the study suggest a high potential for these novel copolymers with high bio-based content to be used for alkyd-type coatings.