Synthetic And Properties Of Self-healing Polyurethane Coating Material

Polymeric materials may suffer from damages all sides including climatic conditions influenced,oxidation,sunlight affected and strong heat,radiation damages during its used,which may separate chemical bond into fragments or lead to harmful changes in chemical structure. A specific performance is discolored, brittle, lower intensity, or even broken and so on,and a direct result of the using life expectancy of material would be curtailed. The research and development of self-healing synthetic polymeric materials have been inspired by biological systems in which damage triggers an autonomic healing response.This is an emerging and fascinating area of research that could significantly extend the working life and safety of the polymeric components for a broad range of applications.This is growing attention by researchers in the field,so the research progress is very quickly.There are many ways to make materials have self-healingcapabilities. One of the way is based on Diels-Alder(DA) reaction and retro-Diels-Alder(r-DA) reaction of conjugated dienes(furan ring) and dienophiles(maleimide ring). There is no need to add any substance to the material when it’s happened DA reactions and r-DA reactions, and just to heat materials treatment can achieve its self-healing abilities.Therefore, people are keen to research this method.In this paper,inspired of this idea and combined with the excellent properties of polyurethane coating materials, we prepare self-healing polyurethane coating materials using DA reactions and r-DA reaction pathways to achieve the goals. Firstly,in the preparation of two-component polyurethane coating material, we add furan ring and maleimide ring during the process of preparing polyurethane component A and B(PU-B),which confirmed by 1H NMR, ATR-IR. Secondly,self-healing materials were prepared by DA reaction and r-DA reaction between the component A and PU-B. Using 1H NMR confirmed that research results: component A and PU-B of DA reaction can be performed at 70℃,and r-DA reaction can be performed at 130℃. Finally,Using 1H NMR、ATR-IR and GPC confirmed the results:after 3 cycles thermally reversible heated treatment for self-healing of polyurethane coating material, we concluded that the polyurethane coating material has the thermal reversible self-healing capabilities.Thereby, experiment reseach were showed that we prepared the different polyurethane coatingmaterials with self-healing abilities. By analyzing the results: self-healing polyurethane coating materials were successfully prepared, and TGA analysis also shows that the polyurethane coating material has the well thermal properties.