A developed Takayanagi model to estimate the tensile modulus and interphase characteristics of polymer nanocellulose composites

This study analyzes the tensile modulus of nanocellulose-reinforced composites by developing the Takayanagi model considering the interphase section and filler size. The model accuracy is assessed by reported experimental moduli of composites and by parametric studies. The estimates of advanced model fit to the measured moduli of numerous examples. Also, it is revealed that the treatment of nanocellulose increases the modulus and thickness of interphase in nanocomposites. The relative modulus (E_r) as the ratio of nanocomposite modulus to the modulus of matrix significantly changes when nanocellulose modulus (E_f) is raised from 50 to 100 GPa; however, E_r unimportantly rises at E_f > 100 GPa. Additionally, nanocellulose radius (R) of 2 nm maximizes the E_r to 1.636, though E_r decreases to 1.09 at R = 58 nm and the variation of E_r is insignificant at R > 20 nm. Furthermore, the interphase moduli (E_i) below 10 GPa meaningfully affect the nanocomposite modulus, but E_i > 10 GPa cannot cause the considerable change in E_r. Therefore, E_r does not change at the high levels of E_f, R and E_i.