Polyvinylchloride intercalated poly(ethylene glycol)-modified-multi-walled carbon nanotube buckypaper composites via resin-infiltration technique

Abstract

In this paper, synthesis and characterization of polymer intercalated carbon nanotube buckypaper for improved structural, morphological, electrical, and thermal properties have been discussed. Resin-infiltration technique was opted for the preparation of polyvinylchloride intercalated poly(ethylene glycol) -modified-multi-walled carbon nanotube buckypaper. The effect of increasing purified nanotube (purified multi-walled carbon nanotube) and functional nanotube (functional multi-walled carbon nanotube) content on the properties of BP-polyvinylchloride/poly(ethylene glycol)/purified multi-walled carbon nanotube and BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube buckypaper composites was investigated, while using same amount of polymer. Results indicated better interaction between polyvinylchloride and functional multi-walled carbon nanotube due to hydrogen bonding relative to polyvinylchloride and purified multi-walled carbon nanotube where no chemical link was present between the two. Fourier transform infrared spectroscopy results confirmed the modification of functional multi-walled carbon nanotube, and formation of buckypaper composite. Scanning electron microscopy micrographs showed better network formation in BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube samples and intercalation of polymer can be seen forming polymer-coated functional multi-walled carbon nanotube network. Thermal stability was found to be improved by the increment of multi-walled carbon nanotube and the difference between the thermal stability of functional multi-walled carbon nanotube and purified multi-walled carbon nanotube buckypaper was also prominent. The maximum degradation temperature (T_max) of functional composite BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube 0.05 (469℃) was higher relative to non-functional BP-polyvinylchloride/poly(ethylene glycol)/purified multi-walled carbon nanotube 0.05 (461℃). The glass transition temperature of BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube 0.05 was found as 249℃, while BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube 0.05 depicted higher T_g of 271℃. Amorphous character of polymer/carbon nanotube -buckypaper composite showed a trend towards crystallinity according to X-ray diffraction results. Purified multi-walled carbon nanotube-based buckypaper presented conductivity up to 1.91 × 10⁻¹S cm⁻¹, while BP-polyvinylchloride/poly(ethylene glycol)/functional multi-walled carbon nanotube 0.01–0.08 had increased conductivity up to 9.88 × 10⁻¹S cm⁻¹.