Vegetable oil cast resins via click chemistry: Effects of cross-linkers

Polymerization of azidated castor, canola, corn, soybean, and linseed oils with two diynes under thermal click chemistry conditions (without a solvent or a catalyst) yielded fully cross-linked polymers (110) with similar density. The use of an aromatic diyne (1,4-diethynylbenzene) as a cross-linker resulted in polymers (15) that showed higher glass transition and strength and lower swelling, water absorption, and sol fraction than corresponding polymers (610) resulting from an aliphatic diyne (1,7-octadiyne). These polymers exhibited behaviors ranging from soft rubbers to hard plastics. Practical applications: Vegetable oil cast resins prepared by click chemistry are potentially useful electroinsulating materials as potting or encapsulating compounds since no by-products are generated.