Carboxyl‐terminated butadiene acrylonitrile rubber/epoxy polymer alloys as damping adhesives and energy absorbable resins

Abstract

Carboxyl-terminated butadiene acrylonitrile (CTBN) liquid rubber/epoxy (diglycidyl ether of bisphenol-A: DGEBA) / diamino diphenyl methane (DDM) resins, in which CTBN was 60 wt % as the major component, were formulated to evaluate the damping and adhesive properties. In cases where acrylonitrile (AN) was 10$18 mol % as copolymerization ratio in CTBN, the blend resins showed micro-phase separated morphologies with rubber-rich continuous phases and epoxy-rich dispersed phases. The composite loss factors (Z) for steel laminates, which consisted of two steel plates with a resin layer in between, depended highly on the environmental temperature and the resonant frequencies. On the other hand, in the case where AN was 26 mol % in CTBN, the cured resin did not show clear micro-phase separation, which means the components achieve good compatibility in nano-scale. This polymer alloy had a broad glass-transition temperature range, which resulted in the high loss factor (Z > 0.1) for the steel laminates and excellent energy absorbability as the bulk resin in a broad temperature range. Also the resin indicated high adhesive strengths to aluminum substrates under both shear and peel stress modes. The high adhesive strengths of the CTBN/epoxy polymer alloy originated in the high strength and the high strain energy to failure of the bulk resin.

Hygrothermal effect on natural frequency and damping characteristics of basalt/epoxy composites

“…Many research works have been carried out in the dynamic characteristics of composite material [1][2][3][4][5][6]. Biggerstaff J.M and Kishi.H et al proved that through toughening of polymer matrix the damping effect can be improved [7,8].Senthil Kumar et.al proved that an increase in fibre content increases the mechanical and damping properties in natural composites [9]. XuLe et.al.…”

Carboxyl-terminated butadiene-acrylonitrile-toughened epoxy/carboxyl-modified carbon nanotube nanocomposites: Thermal and mechanical properties

“…Kishi et al [5] found that though the CTBN/DGEBA/DDM (diamino diphenyl methane) resins indicated high damping performance and high adhesive strength to aluminum substrates, there was always loss of strength of the materials accompanied with the improvement of toughness. The work of Ratna and Banthia [6] showed that the tensile strength and flexural strength of the epoxy resins modified by carboxyl terminated poly(2-ethylhexyl acrylate) decreased rapidly with increase of the rubber.…”

Interfacial control and mechanical properties of carbon black‐reinforced carboxyl‐terminated butadiene acrylonitrile rubber/epoxy polymer composites

“…All the components (liquid rubber, epoxy oligomer, and diamine) were found to react with one another to generate a covalent bonded network, and so the product was not technically an IPN. In a previous study, CTBN/DGEBA/DDM networked polymer blends showed good adhesive and damping properties over a wide range of temperatures . These desirable characteristics were achieved by selecting components that were compatible with one another.…”

“…Our group has previously studied polymer blends consisting of a liquid reactive rubber (carboxyl‐terminated butadiene acrylonitrile rubber (CTBN)), an epoxy resin (diglycidyl ether of bisphenol‐A (DGEBA)), and an aromatic diamine (diamino diphenyl methane (DDM)) . Although CTBN is known to act as a toughening modifier in epoxy resins, in our prior work, it was used as the major component (at 60 wt%) of the polymer blends . All the components (liquid rubber, epoxy oligomer, and diamine) were found to react with one another to generate a covalent bonded network, and so the product was not technically an IPN.…”