Synthesis and characterization of multiwall carbon nanotube/waterborne polyurethane nanocomposites

Abstract

The preparation of thermoplastic nanocomposites of waterborne polyurethane (WBPU) and multiwall carbon nanotubes (MWCNTs) via an in situ polymerization approach is presented. The effects of the presence and content of MWCNTs on the morphology and thermal, mechanical and electrical properties of the nanocomposites were investigated. Carbon nanotubes were modified with amide groups in order to enhance their chemical affinity towards WBPU. Thermogravimetric studies show enhanced thermal stability of the nanocomposites. Scanning and transmission electronic microscopy images prove that functionalized carbon nanotubes can be effectively dispersed in WBPU matrix. Mechanical properties reveal that Young's modulus and tensile strength tend to increase when appropriate amounts of MWCNTs are loaded due to the reinforcing effect of the functionalized carbon nanotubes. Thermal properties show an increase in the glass transition temperature and storage modulus with an increase in MWCNT content. X‐ray diffraction reveals better crystallization of the WBPU in the presence of MWCNTs. The WBPU/MWCNT nanocomposite film containing 1 wt% of MWCNTs exhibits a conductivity nearly five orders of magnitude higher than that of WBPU film. © 2017 Society of Chemical Industry

Multiwalled carbon nanotubes/castor‐oil–based waterborne polyurethane nanocomposite prepared using a solvent‐free method

“…As shown in Figure 13A, the cross‐sectional image of the pure polyurethane film is smooth and flat. Figure 13B,C, corresponding to composites with 0.1 and 0.2 wt% of acid‐MWCNTs, respectively, showed well‐dispersed due to formation of hydrogen bonds between acid‐MWCNTs and polymer matrix 31 . As a result, the preparing WPU/acid‐MWCNTs nanocomposites with the low content of acid‐MWCNTs had a better performance in terms of mechanical properties and thermal stability.…”

Dispersion of multiwalled carbon nanotubes in waterborne polyurethane emulsions derived from alcoholysis products of waste PET and its effect on properties

“…A broad peak at 3,481 cm −1 corresponds to the hydrogen‐bonding NH stretching with urethane carbonyl groups and a peak at 1,539 cm −1 corresponds to CN stretching and δNH stretching. The peaks at 2,970 and 2,848 cm −1 are attributed to the stretching of CH bond in CH 3 and CH 2 groups, respectively . The stretching peaks at 1,716 and 1,645 cm −1 correspond to the urea hydrogen bonded disordered carbonyl group and urethane hydrogen bonded disordered carbonyl group, respectively.…”

“…Inorganic nanoparticles, such as SiO 2 , TiO 2 , ZnO , and clay nanocomposites are widely used to improve thermal stability, mechanical and physical properties of waterborne polyurethanes. Macromolecular organic nanomaterials, such as N ‐doped reduced graphene oxide (NRGO) , carbon canotube , and high aspect ratio nanofibrillated cellulose , are used to endow the WPU with quality electromagnetic interference shielding effectiveness (EMI SE), mechanical properties, thermal properties and water resistance.…”

Synthesis and properties of polydimethylsiloxane/graphene oxide modified, water‐based polyurethane/polyacrylate

“…Figure (c,f,i) suggests that the Young's modulus of WPUA film increased from 19.1 to 25.4 MPa after GO addition, and it increased to 30.6 MPa after PG addition; this suggests improvements in the mechanical strength of the film after the modifier addition. The excellent dispersion of GO and PG enhanced the uniformity of stress distribution and reduced the stress concentration, thereby improving the mechanical properties. Furthermore, the Young's modulus of PG–WPUA was higher than those of previously reported waterborne PU–multiwall carbon nanotubes (7.2 MPa) and PU nanocomposites filled with attapulgite nanorods (9.12 MPa); this suggested that the superior nature of the PG–WPUA films showed great promise for practical applications.…”