Effects of Amino-Functionalized Carbon Nanotubes on the Crystal Structure and Thermal Properties of Polyacrylonitrile Homopolymer Microspheres.

Hailong Zhang,Lianghua Xu,Ling Quan

doi:10.3390/polym9080332

Abstract

Amino-functionalized multi-walled carbon nanotube (amino-CNT)/polyacrylonitrile (PAN) microspheres with diameter of about 300–400 nm were prepared by in situ polymerization under aqueous solution. The morphology, crystal structure, and thermal properties of amino-CNTs on a PAN homopolymer were investigated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, X-ray diffraction, and differential scanning calorimetry. The results showed that the amino-CNTs had a significant influence on the morphology of microspheres, and the PAN matrix were grafted onto the surface of amino-CNTs with interfacial bonding between them. The XRD studies showed that the crystal size of amino-CNT/PAN microspheres with lower crystallinity was bigger than in the control PAN homopolymer. The analysis of thermal properties indicated that the amino-CNT/PAN microspheres with lower glass transition temperature had a lower initial temperature and velocity of evolving heat during the exothermic processing as compared with the PAN homopolymer. These results suggested that the incorporation of amino-CNTs into the PAN homopolymer matrix was beneficial for controlling the heat released during the stabilization processing.

Highlights

Due to their unique structure and exceptional properties, such as high mechanical strength and excellent electrical and thermal properties, carbon nanotubes (CNTs) have received much attention from researchers in various fields [1]
CNTs and formed coating around the outer. These results show that the microspheres with amino-CNTs exhibit. These results show that the microspheres with amino-CNTs exhibit homogeneous dispersion as well homogeneous dispersion well asthegood bonding between homopolymer as good interfacial bondingas between
Transmission electron microscopy (TEM) images, images, showed showedthat thatamino-CNTs amino-CNTs were homogenously dispersed in the PAN homopolymer matrix and that they enhanced the interfacial homogenously dispersed in the PAN homopolymer matrix and that they enhanced the interfacial bonding between the amino-CNTs and the PAN matrix

Summary

Introduction

Due to their unique structure and exceptional properties, such as high mechanical strength and excellent electrical and thermal properties, carbon nanotubes (CNTs) have received much attention from researchers in various fields [1]. The homogeneous dispersion of CNTs in a polymer matrix remains a challenge owing to the strong van der Waals forces between the tubes and the large aspect ratio. Various methods have been studied to solve these problems, such as non-covalent and covalent modification [2,3]. Non-covalent modification does not change the structure of CNTs, but it is hard to maintain the homogeneous dispersion and improve the interfacial interaction. Covalent modification is considered to be an effective method to obtain the most homogeneous dispersion and the better interfacial bonding between the CNTs and polymer matrix [4]

Methods

Discussion

Conclusion