Integrating plant oils into thermally curable main-chain benzoxazine polymers via ADMET polymerization

A novel biobased alpha,omega-diene bearing a thermally curable benzoxazine group is synthesized and polymerized via acyclic diene metathesis (ADMET) using Hoveyda-Grubbs second generation catalyst. The benzoxazine-containing diene monomer was designed based on 10-undecenoic acid, a castor oil derived platform chemical. The M-n and crosslinker content can be modulated by using a monofunctional comonomer to end-cap polymer chains. Differential scanning calorimetry was used to demonstrate that obtained thermoplastic prepolymers are able to yield thermosets after thermally activated ring opening polymerization just simply by heating up to around 200 degrees C. Thermal and mechanical properties of the cured polybenzoxazines are also discussed. (C) 2014 Elsevier Ltd. All rights reserved.