Biobased poly(vinyl ether)s derived from soybean oil, linseed oil, and camelina oil: Synthesis, characterization, and properties of crosslinked networks and surface coatings

Abstract

A series of novel plant oil (PO)-based poly(vinyl ether)s were produced that varied with respect to PO composition and molecular weight (MW). The POs investigated were soybean oil, linseed oil, and camelina oil. All of the polymers were liquids at room temperature and were used to produce crosslinked networks, both as free-standing films and as surface coatings on steel substrates. Crosslinking was achieved at ambient conditions through the process of autoxidation. Viscosity of the neat polymers as well as the viscoelastic and mechanical properties of crosslinked networks were highly dependent on parent PO composition. At a given polymer MW, viscosity decreased with increasing PO unsaturation, while glass transition temperature, Young’s modulus, and tensile strength of crosslinked networks increased with increasing PO unsaturation. For polymers derived from the most highly unsaturated PO, i.e. linseed oil, impact resistance of coatings was significantly compromised, due to the relatively high crosslink density of these coatings. Overall, these results demonstrated that viscosity and the properties of crosslinked films based on these novel PO-based poly(vinyl ether)s could be tailored through selection of the parent PO and control of polymer MW. This class of highly bio-based polymers appears to have particular utility for the production of one-component, ambient-cured coatings. One component, ambient-cured thermoset coatings are highly desired because of their ease of use, lower waste production, and energy cost savings compared to other thermoset coating systems.