Performance of CTBN(carboxyl-terminated poly (butadiene-co-acrylonitrile))-EP(diglycidyl ether of bisphenol-A (DGEBA)) prepolymers and CTBN-EP/polyetheramine (PEA) system

Abstract

CTBN-EP prepolymers were synthesized from CTBN and epoxy resin under the catalysis of HTMAB. FTIR analyses indicate the formation of ester group between the carboxyl group of CTBN and the oxirane group of epoxy resin. The viscosity of modified prepolymer increases with CTBN content increasing, but the epoxy value of the prepolymer decreases greatly. DSC analyses verify that CTBN affects the curing process of CTBN-EP/PEA system. Mechanical testing presents the improved toughness of CTBN-EP/PEA curings for the decrease of tensile strength, flexural strength and compressive strength, and increase of impact strength and elongation-at-break with the CTBN content increasing. SEM micrographs show the rubber phase with many holes in diameter about 0.5-1.5 μm is formed when CTBN content is lower than 10 phr. However, the pattern of SEM graph shows some stalactite-like strips when CTBN content is higher than 15 phr. Furthermore, the SEM image of 25 phr CTBN sample forms a kind of co-continuous structure.

Effect of Hybridization of Carboxyl‐Terminated Acrylonitrile Butadiene Liquid Rubber and Alumina Nanoparticles on the Fracture Toughness of Epoxy Nanocomposites

“…This could decrease the intensity of the peaks at 915 and 830 cm −1 . The intensity of [sbond]C[tbond]N absorption peak at 2,237 cm −1 , appeared in the spectrum of UEC15, was decreased compared with that of CTBN, which was probably due to the lower volume fraction of CTBN in the sample . These findings confirmed the reaction of epoxy resin with CTBN to some extent even in the absence of the hardener.…”

“…The optimum balance of the mechanical properties and toughness was reported to be at CTBN concentration in the range 15–20 phr . It has been shown that the rubber toughening of epoxies results in superior fracture toughness, however, strength and modulus both decrease when compared with those of the neat resins .…”

Comparative Study on the Impact Wedge-Peel Performance of Epoxy-Based Structural Adhesives Modified with Different Toughening Agents

“…Viscosity is also an important physical property of epoxy adhesives. Normally viscosity increases with the addition of PTPU or CTBN [ 46 ]. As shown in Figure 5 , the viscosity of the PTPU-modified epoxy adhesive was twice as high as that of the CTBN-modified epoxy adhesive, because PTPU has higher viscosity than CTBN.…”

Effects of toughened polyester on fatigue behavior of glass fiber reinforced polyester composite for wind turbine blade

“…The FTIR spectra of CTBN reacted with 1,4‐BDGE (Figure 3) presented the absorption bands related to the carboxylic group of CTBN which are not observed and the peak at 1735.85 cm −1 related to the formation of ester functional group. On the other hand, when 1,4‐BDGE was added to CTBN liquid rubber, the epoxy ring of 1,4‐BDGE was opened by the carboxylic group of CTBN, then the carboxylic group was converted to ester functional group 24 and absorption band related to acidic‐OH of the carboxylic group disappeared. The spectral results indicated that CTBN liquid rubber was successfully modified and treated polymer exhibited a combination of the structural features of both CTBN and 1,4‐BDGE.…”