synthesis and characterization of nanocomposites based on thermoplastic polyurethane/cellulose nanocrystals

The purpose of this research was to prepare thermoplastic polyurethane (tpu) nanocomposites based on polycaprolactone (pcl) soft segments and cellulose nanocrystals (cncs), in order to investigate the effects of incoroporating cnc on their mechanical properties. tpu was synthesized using pcl with a molecular weight of 2000 as soft segment, hexamethylene diisocyanate (hdi) as hard segment, and 1,4 butanediol (bdo) as chain extender, and then tpu/cncs nanocomposites (5% w/w) was prepared using solution casting method. the chemical structure and hydrogen bonding index (hbi) of cellulose nanocrystals, polyurethanes and their nanocomposites were analyzed by fourier-transform infrared (ftir) spectroscopy, and the mechanical properties of nanocomposites were examined by tensile test. according to the results, hbi of pu nanocomposite increased with the addition of cellulose nanocrystals, and improvement in mechanical properties of nanocomposites was noticeable due to the presence of cellulose nanocrystals.  the purpose of this research was to prepare thermoplastic polyurethane (tpu) nanocomposites based on polycaprolactone (pcl) soft segments and cellulose nanocrystals (cncs), in order to investigate the effects of incoroporating cnc on their mechanical properties. tpu was synthesized using pcl with a molecular weight of 2000 as soft segment, hexamethylene diisocyanate (hdi) as hard segment, and 1,4 butanediol (bdo) as chain extender, and then tpu/cncs nanocomposites (5% w/w) was prepared using solution casting method. the chemical structure and hydrogen bonding index (hbi) of cellulose nanocrystals, polyurethanes and their nanocomposites were analyzed by fourier-transform infrared (ftir) spectroscopy, and the mechanical properties of nanocomposites were examined by tensile test. according to the results, hbi of pu nanocomposite increased with the addition of cellulose nanocrystals, and improvement in mechanical properties of nanocomposites was noticeable due to the presence of cellulose nanocrystals.  the purpose of this research was to prepare thermoplastic polyurethane (tpu) nanocomposites based on polycaprolactone (pcl) soft segments and cellulose nanocrystals (cncs), in order to investigate the effects of incoroporating cnc on their mechanical properties. tpu was synthesized using pcl with a molecular weight of 2000 as soft segment, hexamethylene diisocyanate (hdi) as hard segment, and 1,4 butanediol (bdo) as chain extender, and then tpu/cncs nanocomposites (5% w/w) was prepared using solution casting method. the chemical structure and hydrogen bonding index (hbi) of cellulose nanocrystals, polyurethanes and their nanocomposites were analyzed by fourier-transform infrared (ftir) spectroscopy, and the mechanical properties of nanocomposites were examined by tensile test. according to the results, hbi of pu nanocomposite increased with the addition of cellulose nanocrystals, and improvement in mechanical properties of nanocomposites was noticeable due to the presence of cellulose nanocrystals.