The surface modifications of multi-walled carbon nanotubes for multi-walled carbon nanotube/poly(ether ether ketone) composites

Abstract

Please cite this article as: Z. Cao, L. Qiu, Y. Yang, Y. Chen, X. Liu, The surface modifications of multi-walled carbon nanotubes for multi-walled carbon nanotube/poly (ether ether ketone) composites, Applied Surface Science (2015), http://dx.Abstract The effects of surface modifications of multi-walled carbon nanotubes (MWCNTs) on the morphology, dynamic mechanical and tribological properties of multi-walled carbon nanotube/poly (ether ether ketone) (MWCNT/PEEK) composites have been investigated. MWCNTs were treated with mixed acids to obtain acid-functionalized MWCNTs. Then the acid-functionalized MWCNTs were modified with ethanolamine (named e-MWCNTs). The MWCNT/PEEK composites were prepared by a solution-blending method. A more homogeneous distribution of e-MWCNTs within the composites was found with scanning electron microscopy. Dynamic mechanical analysis demonstrated a clear increase in the storage modulus of e-MWCNT/PEEK composites because of the improved interfacial adhesion strength between e-MWCNTs and PEEK. Furthermore, the presence of e-MWCNTs caused an A c c e p t e d M a n u s c r i p t 2 enhancement in the glass transition temperature of the composites. Wear tests have shown that the friction coefficient of e-MWCNT/PEEK composites decreased significantly during the test after the running-in period. This suggests that there is an obvious improvement in tribological properties of e-MWCNT/PEEK composites. Overall, the e-MWCNT/PEEK composites have exhibited improved properties and are promising for their applications in industry.

Functionalization of multi-walled carbon nanotubes and their effect on the tribological properties of poly(ether ether ketone) composites

“…However, tribo‐materials exhibit different tribological performances in different operating conditions. To study the tribological properties of the PEEK composites in different working conditions, we performed two model experiments: pin‐on‐disc and block‐on‐ring. A schematic of the UMT‐2 tribometer is shown in Fig.…”

“…However, an ideal tribo‐material is expected to have a lower coefficient of friction and wear rate. Based on observations, the incorporation of appropriate fillers is an effective method to decrease the coefficient of friction and improve the wear resistance of PEEK resins …”

Mechanical Properties of Carbon Nanotubes-Polymer Composites

“…These oxidative treatments usually result in shortening of the CNTs' length and formation of surface reactive groups, such as hydroxyl, carbonyl, and mainly Carboxyl. Furthermore, the inorganic impurities of the Al-Fe catalyst used in the preparation of CNTs are solubilized by the acids and the concentration of the impurities is gradually decreased with treatment time [20,23,26,27]. It has been shown that acid functionalized CNTs has good dispersibility in water and organic solvents, and the carboxylic functional groups give a stronger nanotube-polymer interaction, leading to enhanced values in mechanical properties of the CNTs/polymer composite [27,28].…”

Comparative study of the effects of nano‐sized and micro‐sized CF and PTFE on the thermal and tribological properties of PEEK composites

“…As a high‐performance semi‐crystalline thermoplastic polymer, poly‐ether‐ether‐ketone (PEEK) has outstanding mechanical properties, chemical inertness, and good thermal stability over a wide temperature range, which makes it widely used as a replacement for metal components in many applications such as the bearing materials, bone implants, and piston rings . However, it is difficult to use PEEK in pristine form because of its high friction coefficient and stick‐slip behavior . In order to solve these problems, many researchers have focused on the tribological property improvements of the PEEK by adding a variety of fillers such as SiO 2 , Al 2 O 3 , carbon fibers (CF), graphene, PTFE, carbon nanotubes etc., as well as their various combinations .…”

“…However, it is difficult to use PEEK in pristine form because of its high friction coefficient and stick‐slip behavior . In order to solve these problems, many researchers have focused on the tribological property improvements of the PEEK by adding a variety of fillers such as SiO 2 , Al 2 O 3 , carbon fibers (CF), graphene, PTFE, carbon nanotubes etc., as well as their various combinations . Among these various lubricating fillers, CFs and PTFE particles have been widely used because of their excellent properties.…”