Curing Characteristics and Thermal Properties of Epoxidized Soybean Oil Based Thermosetting Resin

Abstract

Epoxidized soybean oil (ESO) was thermally cured using methylhexahydrophthalic anhydride (MHHPA) curing agent in the presence of 2-ethyl-4-methylimidazole (EMI) catalyst. The curing characteristics of ESO/MHHPA/ EMI systems were characterized using Fourier transform infrared spectroscopy (FTIR), a dynamic mechanical analyzer (DMA) and a differential scanning calorimeter (DSC). FTIR spectra showed that the polyesterification rate in ESO/MHHPA/EMI systems increased with increasing of the catalyst concentration. DSC thermograms indicated that EMI-catalyzed ESO/MHHPA systems experienced enthalpy relaxation at low EMI concentration whereas the extent decreased with increasing of the EMI concentration. There is a direct relationship between the degree of conversion and crosslink density of the thermal cured ESO/MHHPA/EMI systems with EMI concentration. The curing characteristics of thermal curable ESO thermosetting resins were found to have influence on the thermal properties of the ESO systems. It was determined that the glass transition temperature (T g ) and storage modulus (E 0 ) of cured ESO increased with increasing the EMI concentration whereas the damping properties of the ESO/MHHPA/EMI systems exhibited the reverse trend. It was found that the thermally curable ESO thermosetting resins experienced a two-stage thermal decomposition process.

Vegetable oil-derived epoxy monomers and polymer blends: A comparative study with review

“…Similar behavior was also found in ELO replacement of diglycidyl ether of bisphenol F resin [78]. The plasticizing effect of saturated FAs and/or the different reactivity of ESO and DGEBA leads to a broad distribution of chain segment mobilities [79] and indicate a heterogeneous polymer network [80]. Broad T g range behavior was not found in the EGS-DGEBA systems.…”

A simple and novel method to design flexible and transparent epoxy resin with tunable mechanical properties

“…It is obvious that the addition of MR can lower T g of the epoxy resin and this phenomenon becomes more significant when the MR content is 25 wt%, as shown in Fig. (a) and Table , demonstrating that MR acts as a flexibilizer . E ′ of epoxy resins with various MR contents are presented in Fig.…”

Synthesis of a novel azaphosphorine flame retardant and its application in epoxy resins

“…To further study the effect of ADDPP‐OH on the glass‐transition temperature ( T g ) value of the cured epoxy thermosets, the rubber elasticity equation [eq. ()] was used to calculate the crosslinking density: where ν c is the crosslinking density for the cured EP (mol/m 3 ), E ′ is the storage modulus of the epoxy thermosets in the rubbery plateau region at T g + 40 °C (Pa), R is the universal gas constant (8.314 J K −1 mol −1 ), and T is the absolute temperature (K).…”