Self-healing, high-performance, and high-biobased-content UV-curable coatings derived from rubber seed oil and itaconic acid

Development of self-healing UV-curable coatings from biorenewable resources is of great significance for sustainable development and environmental protection. In this work, a biobased UV-curable oligomer was firstly synthesized by ring-opening reaction of epoxidized rubber seed oil with glycidyl methacrylate-modified itaconic acid precursor. Chemical structure of the obtained oligomer was then characterized by FT-IR, 1H NMR, and gel permeation chromatography. Subsequently, a series of UV-curable coatings were prepared by co-photopolymerization of the oligomer with the hydroxyethyl methacrylate diluent. UV-curing behaviors, biobased contents, and ultimate properties such as thermal, mechanical, and coating properties were studied. Furthermore, dynamic transesterification reactions were activated at elevated temperatures in the presence of a Zinc catalyst, thus self-healing, shape memory, malleable, and recyclable properties were further investigated. Notably, the obtained UV-curable coatings demonstrated good self-healing properties (86–100% at 200 °C for 30 min), high biobased contents (45.4–72.3%), and high performance (tensile strength and glass transition temperature up to 22.4 MPa and 119.2 °C, respectively).