Rapid microwave-assisted ionothermal dissolution of cellulose and its regeneration properties

Abstract

Introduction of the strategy of anhydrous calcium carbonate protection incorporated with the drop by drop reaction, high-purity 1-butyl-3-methylimidazolium chloride ([Bmim] Cl) was prepared at reaction temperature of 80°C for only 10 h. Cellulose samples from different biomass sources (with different degree of polymerization characteristic) could be rapidly (no more than 10 minutes) and completely dissolved in the [Bmim] Cl using a microwave-assisted ionothermal route. Homogeneous cellulosic regenerates with high degree of polymerization and thermal stability characteristics were obtained through a coagulation process in water. Furthermore, the dissolved celluloses were readily regenerated into solid products such as casting films and spinning fibers, which exhibited high transparency and flexibility, as well as superior mechanical properties of over 300 MPa (tensile strength) more than those of cellulose samples reported. This study therefore provides a new process for the synthesis of high-purity [Bmim] Cl for the highly efficient dissolution of cellulose to produce high performance cellulosic materials for various applications such as flexible electronic, optoelectronic, soft robots.