초록 |
Bio-based polyurethane (BPU)/cellulose nanofiber elastomer composites synthesized using castor oil based polyol were prepared by adding cellulose nanofibers during preparation of prepolymer. Chemical modification of cellulose nanofibers was performed to enhance dispersion of cellulose nanofibers, and modified cellulose nanofibers (m-CNFs) were covalently bonded with BPU matrix to improve interfacial adhesion. The tensile strength and modulus of the m-CNF reinforced BPU composites were significantly improved, as compared to the neat BPU. Dynamic mechanical analysis revealed that the storage modulus was increased and the tan delta peak was shifted towards higher temperatures by incorporation of m-CNF. Furthermore, the m-CNF enhanced thermal stability of the BPU composites and activation energy of thermal decomposition was evaluated by Horowitz-Metzger method. This research was supported by National Research Foundation of Korea. (Project No. 2011-0028966) |