Improved resistance-welded joints of thermosetting composites via flame-grown carbon nanotube

Resistance welding of carbon fibre reinforced PEKK by means of CNT webs

“…Efforts to enhance adhesion to the metallic meshes include sandblasting, aryl diazonium grafting, silane grafting, 31 organosilane coating 36 and even coating with flame grown carbon nanotubes (CNT). 35…”

“…39 CNT web heating elements can be efficiently produced at an industrial scale, are not affected by corrosion, are highly flexible and are of negligible weight. The web, which is comprised of CNT of around 10 nm diameter and 300 μ m length, is thin, highly conformable and porous, and, being composed entirely of carbon, highly compatible with thermoplastics, thereby greatly facilitating interpenetration of the interface polymer 35 and thus the inclusion effect of the web within the joint can be mitigated. The flexibility of the CNT web allows the welding of complex mating surfaces.…”

“…2,4,19,21 Pressures between 2 and 16.3 MPa have been reported. 4,21,35 Dubé et al 28 showed that a smaller wire diameter would reduce its inclusion effect. However, because of the lack of chemical bonding between the metallic mesh and the polymer, physical entanglement is considered as the major, if not only, bonding mechanism at the metal/ polymer interface.…”

“…Efforts to enhance adhesion to the metallic meshes include sandblasting, aryl diazonium grafting, silane grafting, 31 organosilane coating 36 and even coating with flame grown carbon nanotubes (CNT). 35 Carbon fibre reinforcement film "organo" sheets have been studied as heating elements but require thorough removal of the polymer from the electrical connection areas, and high clamping pressure to avoid critical problems such as poor reproducibility, 22 and excessive heating at the junctions. 25 Scaling, 27 and particularly temperature nonuniformity when using unidirectional (UD) organo sheets, are also problematic.…”