Preparation and Mechanical Properties of Epoxy Resin Reinforced with Jeffamines-Grafted Carbon Nanotubes

Abstract

The increasing proliferation and application of advanced polymer composites requires higher and broader performance resin matrices. Poly(oxypropylene) with –NH2 end-groups has been widely used to toughen epoxy resins, but the strength of resin matrix may be reduced due to the addition of flexible segments in the crosslinking network. Carbon nanotubes (CNTs) have been paid more and more attention in recent years because of their superior thermal and mechanical properties. In this paper, CNTs grafted with Jeffamines T403 were used to simultaneously improve the reinforcement and toughening of an epoxy resin. The untreated multi-walled carbon nanotubes (u-MWNTs) were functionalized with amine groups according to three steps: carboxylation, acylation, and amidation. The f-MWNTs were characterized by Fourier transform infra-red (FTIR) and X-ray photoelectron spectroscopy (XPS). The experimental results indicated that the T403 was grafted to the surface of MWCNTs. The mechanical and thermal properties of epoxy with f-MWNTs were investigated. The tensile and flexural strength increased by 7.77 % and 7.03 % after adding 0.5wt% f-MWCNTs without sacrificing the impact toughness. At the same time, dynamic mechanical thermal analysis (DMTA) showed that the glass transition temperature (Tg) of epoxy with f-MWNTs were increased. The fracture surface of epoxy with f-MWNTs was observed by scanning electron microscopy (SEM) to understand the dispersion of f-MWNTs in epoxy matrix and interfacial adhesion between f-MWNTs and epoxy matrix, which can be attributed to the strong interfacial bonding between f-MWNTs and epoxy resin.

Preparation and Properties of Highly Electroconductive and Heat-Resistant CMC/Buckypaper/Epoxy Nanocomposites

“…From the experimental results, it could be proven that epoxy resin nanocomposites reinforced with CMC/buckypapers have a positive influence on the thermal stability and lower degradation rate compared to pure polymer. This is a consequence of the high thermal conductivity of carbon nanotubes, which can efficiently enhance the heat transport from polymer to CNT to polymer [26]. In addition, dispersion is a key parameter deciding the thermal stability performance of polymer composites with particle fillers.…”

Multifunctionalized Carbon Nanotubes Polymer Composites: Properties and Applications

“…For instance, the addition of 1 wt% of MWCNTs in the polystyrene by solution evaporation procedure brought about 36-42 and almost 25 % enhancement in tensile modulus and tensile strength, in order (Suemori et al 2013). Whereas, the improvement in indentation resistance was recorded up to 3.5 times by supplementing 2 wt% SWCNTs in epoxy resin (Shi et al 2009;Huaming et al 2005). Some studies observed a major enhancement in modulus and hardness (1.8 times and 1.6 times) with the integration of 1 wt% MWCNTs in polyvinyl alcohol (Song et al 2013).…”

“…Oxidized CNTs well show an exceptional stability in other solvents including caprolactam, which is applied in the production of polyamide (Frohlich et al 2013). Study on carboxylation of CNTs has shown a considerable enhancement in interfacial bonding between CNTs and polymer matrices, which consecutively triggered stronger CNTs-polymer interaction, leading to improvement of Young's modulus and mechanical strength (Hashimi et al 2012;Shi et al 2009). Conversely, dramatic amounts of induced defects throughout functionalization hamper the intrinsic mobility of carriers along CNTs, which is not desirable in any case (Naeimi et al 2009;Liu et al 2011;Zhong et al 2011).…”

“…For example, pullout process proposes that effective load transfer arises from the polymer matrix to the outer layer of CNTs, caused by the sturdy covalent bonding within its interfacial region (Shi et al 2009). This observation anticipated that the efficiency of property improvement relies on the form of CNTs, processing technique, and compatibility between CNTs and polymeric matrix (Pascual et al 2012).…”

Studies of thermal, mechanical properties, and kinetic cure reaction of carboxyl‐terminated polybutadiene acrylonitrile liquid rubber with diepoxy octane

“…3,7,8 Applicate flexible curing agents, such as Jeffamine, can be considered as one of the most effective methods to reduce the hardness of the epoxy network (Jeffamine is a low viscosity diamine with flexible and linear polyether backbone). 9 In addition, the usage of liquid rubbers is another successful method for reducing the hardness, improvement of the toughness, and decrease in the glass transition temperature (T g ), and modulus of the epoxy network (McGarry, first reported this method). 10 Among different types of liquid rubbers employed in this context, carboxyl terminated poly butadieneacrylonitrile (CTBN) has attracted considerable attention from the researchers.…”