Epoxidized soybean oil grafted with CTBN as a novel toughener for improving the fracture toughness and mechanical properties of epoxy resin

• Published in: Polymer journal Vol. 52; no. 3; pp. 345 - 357
• Main Authors: Bach, Quang-Vu, Vu, Cuong Manh, Vu, Huong Thi, Hoang, Thai, Dieu, Tran Vinh, Nguyen, Dinh Duc
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.03.2020; Nature Publishing Group
• Subjects: 140/131; 639/166; 639/638/455/303; 639/638/455/958; Acrylonitrile butadiene resins; Biomaterials; Bioorganic Chemistry; Bisphenol A; Carboxyl group; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Crack propagation; Curing agents; Epoxy resins; Fourier transforms; Fracture toughness; Grafting; Infrared analysis; Liquid chromatography; Mechanical properties; NMR; Nuclear magnetic resonance; Original Article; Polymer Sciences; Ring opening; Soybean oil; Soybeans; Spectrum analysis; Surfaces and Interfaces; Tensile strength; Thin Films; Vegetable oils
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1038/s41428-019-0275-3

We prepared epoxidized soybean oil (ESO) grafted with carboxyl-terminated poly(acrylonitrile-co-butadiene) (CTBN) (ESO-g-CTBN) by a ring-opening reaction between the epoxide group and the carboxyl group. The structural features of the resulting product were determined using modern analytical techniques, such as Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance ( 1 H NMR) spectroscopy, and gel permeation chromatography (GPC). The ESO-g-CTBN was applied as a toughener for an epoxy resin-based composite that was fabricated by blending the epoxy resin with diethylenetriamine (DETA) as the curing agent. The main aim of this procedure is to simultaneously improve the mechanical properties and fracture toughness of a bisphenol A-based epoxy resin. When 15 phr of ESO-g-CTBN was added to the EP/DETA mixture, the resin fracture toughness ( K IC ) and tensile strength increased from 0.65 to 1.09 MPa m 1/2 and from 34.42 to 42.55 MPa, respectively. The ESO-g-CTBN existed in the EP matrix as a separate phase and induced an increase in the K IC via stopping crack growth or changing the crack direction. The epoxydized soybean oil grafted with CTBN (ESO-g-CTBN) was synthesized from ring opening reaction between epoxide group and carboxyl group. The ESO-g-CTBN help to improve the fracture toughness of epoxy resin by the mechanism as shown in the figure.