LAUSR

Abstract Poly(urethane-thiourethane) triblock copolymer nanotube composites have been synthesized by reacting hexamethyl diisocyanate, polyethylene glycol, chain extended with two different diols 3,6-dioxa-1,8-octanedithiol (DODT), 3,7-dithia-1,9-nonanedithiol (DTDT) and different weight percentage of single-walled carbon nanotubes (SWCNTs). The structure of the triblock copolymers and nanocomposites were analyzed by Raman and DSC. Storage modulus (G′), loss modulus (G″) and viscoelastic properties of the nanocomposites were explored by dynamic mechanical analysis and melt viscosity was studied using parallel-plate rheometer. The nanotube composites were obtained as tough transparent films and are thermally stable at 450 °C, exhibiting glass transition temperatures at −65 °C for DODT based composites and −58 °C for DTDT based composites. The rheology and morphological properties of Poly(urethane-thiourethane) (PTU) composites of various composition are discussed. The sample PU-34-SH-CNT and PU-34 OSH-CNT exhibits high G′ value of 7000 MPa and 4000 MPa. Phase separation was observed in melt flow at high shear rate for both SH-CNT and OSH-CNT composites. These copolymer nanocomposites behave like a pseudoelastic, single-phase homopolymer melts and could be used in high temperature coating applications.