Multifunctional curing component for epoxidized novolac resin by grafting poly (amidoamine) on carbon nanotubes using a divergent method

Abstract

Poly(amidoamine)-grafted carbon nanotube (CNTD) was synthesized and used as a multi-component curing agent for epoxidized novolac resin (ENR). This composite and curing agent can improve thermal stability of the resin due to its tubular graphitic core and also dendritic amino-functionalities. The ENR was cured in the presence of different amounts of CNTD. Then, the thermal degradation temperature and also char content of the products were compared with the ethylenediamine-cured ENR.Successful functionalization of oxidized carbon nanotubes with poly(amidoamine) was evaluated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and thermogravimetric analysis. According to the thermogravimetric analysis results, char content of ethylenediamine-cured ENR is 44.7% which increased to 54.6%, 55.5%, and 56.9% by the addition of 3, 5, and 8 wt% of CNTD into the resin matrix. Also, addition of CNTD content increased thermal stability of the composites. The tubular structure of CNTD was observed by scanning and transmission electron microscopies. KEYWORDS carbon nanotube, epoxidized novolac resin, poly(amidoamine), thermal stability

An experimental investigation on low-cycle fatigue behavior of GO-NH2-reinforced epoxy adhesive

“…In the GO spectrum, the peak of 3439 cm À1 , 1750 cm À1 , and 1638 cm À1 is related to the hydroxyl tensile vibrations amplified by water adsorption, the tensile vibrations of the carboxyl groups (C¼O), and the tensile vibrations of aromatic rings (C¼C), respectively. 27,48 After functionalization of GO with 3-APTES, the peak of 3439 cm À1 is related to the tensile vibrations of NH, which overlaps with the tensile vibration of OH 49 and the peaks of 2929 cm À1 and 2856 cm À1 are related to the symmetric and asymmetric tensile vibrations of the CH 2 units, respectively, 50 which confirms the successful reaction of the 3-APTES modifier agent with GO. The 1742 cm À1 peak is related to the tensile vibration of the double bond (C¼O) and the 1630 cm À1 peak is related to the N-H flexural vibration.…”

Hyperbranched Poly(amidoamine)‐Grafted Graphene Oxide as a Multifunctional Curing Agent for Epoxy‐Terminated Polyurethane Composites

“…Poly(amidoamine) (PAMAM) is among the most common hyperbranched amine‐terminated polymers for curing of epoxy‐containing resins. Synthesis of PAMAM is commonly carried out by repeated addition of acrylic esters to amine functionalities through the Michael addition reaction and reacting the resulting ester group with an alkyl diamine through the amidation reaction [39–42] . Application of PAMAM as a curing agent containing high content of amine functionalities increases degree of network density.…”