Study on the rheological properties of regenerated cellulose/thermoplastic polyurethane blend spinning solutions

The rheological behavior of regenerated cellulose/thermoplastic polyurethane (TPU) blend spinning solutions was investigated by an advanced rotary rheometer. The viscosity decreases with increasing shear rates, exhibiting shear thinning behavior. The storage modulus of G′ and the loss modulus G″ both increase with increasing frequencies, while the complex viscosity decreases gradually. The non-Newtonian index increases while the flow activation energy decreases with increasing TPU content. The composite fibers were characterized by FTIR and XRD, indicating that the addition of TPU into regenerated cellulose matrix destroyed the crystallinity to some extent. The mechanical property tests illustrate that the toughness of the fiber was greatly improved with the incorporation of TPU.