Abstract:Rosin‐modified o‐cresol novolac epoxy resin (AEOCN) was synthesized by condensation of rosin acid with o‐cresol formaldehyde novolac resin (AOCN). The AEOCN resin was further epoxidized using epichlorohydrin and sodium hydroxide. Rosin‐based imidoamine curing agents (IAMDK, IASDK, and IAEDK) were also prepared by reacting dimaleopimaryl ketone (DMPK), a dimerized rosin product with aromatic diamines. The chemical structures of all synthesized products were confirmed by FTIR, 1H‐NMR, 13C‐NMR, and DEPT‐135° spec… Show more
“…The activation energies ( E a ) of the thermal decomposition reaction for the cured epoxy resin samples (PEMPAE & TMPAE) using IAMDK, IASDK, IAEDK, DMPK, and DDE curing agents were determined from TGA data according to the method used by Dharwadkar and Kharkhanawala 30 as outlined in our previous study. 23 Table 4 enlists the decomposition activation energies for all samples. The Table 4 showed a greater value of activation energy in case of rosin based crosslinkers cured epoxies than that of the commercial one.…”
Section: Resultsmentioning
confidence: 99%
“…These rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) were synthesized via nucleophilic addition reaction of diamino diphenyl ether (DDE) and dimaleopimaryl ketone (DMPK), a dehydrodecarboxylated derivative of MPA according to the procedure described in our previous study. 23 Figure 2.The reaction scheme for the synthesis of rosin-based imidoamine curing agents IAMDK/IASDK/IAEDK.…”
This paper includes the curing of previously synthesized multifunctional bio-based epoxy resins (PEMPAE/TMPAE) with rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) which are nucleophilic addition reaction products of diamino diphenyl ether (DDE) and dimaleopimaryl ketone (DMPK), a dehydrodecarboxylated derivative of MPA. Curing dynamics of rosin-based epoxy resins (PEMPAE/TMPAE) with rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) were evaluated using differential scanning calorimetry. For comparison, the bio-based epoxy resins were also cured with rosin derivative dimaleopimaryl ketone (DMPK) and commercial-based diamino diphenyl ether (DDE). The universal testing machine and thermogravimetric analyzer) were used to measure the mechanical properties and thermal stability of the cured epoxy samples. The samples’ chemical resistance was assessed by calculating the weight loss in percent after they were submerged in solutions of NaOH, HCl, and NaCl. We also used scanning electron microscopy (SEM) to examine the morphological changes. Rosin-based epoxy cured with imidoamine curing agents outperformed the commercial epoxy in terms of performance.
“…The activation energies ( E a ) of the thermal decomposition reaction for the cured epoxy resin samples (PEMPAE & TMPAE) using IAMDK, IASDK, IAEDK, DMPK, and DDE curing agents were determined from TGA data according to the method used by Dharwadkar and Kharkhanawala 30 as outlined in our previous study. 23 Table 4 enlists the decomposition activation energies for all samples. The Table 4 showed a greater value of activation energy in case of rosin based crosslinkers cured epoxies than that of the commercial one.…”
Section: Resultsmentioning
confidence: 99%
“…These rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) were synthesized via nucleophilic addition reaction of diamino diphenyl ether (DDE) and dimaleopimaryl ketone (DMPK), a dehydrodecarboxylated derivative of MPA according to the procedure described in our previous study. 23 Figure 2.The reaction scheme for the synthesis of rosin-based imidoamine curing agents IAMDK/IASDK/IAEDK.…”
This paper includes the curing of previously synthesized multifunctional bio-based epoxy resins (PEMPAE/TMPAE) with rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) which are nucleophilic addition reaction products of diamino diphenyl ether (DDE) and dimaleopimaryl ketone (DMPK), a dehydrodecarboxylated derivative of MPA. Curing dynamics of rosin-based epoxy resins (PEMPAE/TMPAE) with rosin-based imidoamine curing agents (IAMDK/IASDK/IAEDK) were evaluated using differential scanning calorimetry. For comparison, the bio-based epoxy resins were also cured with rosin derivative dimaleopimaryl ketone (DMPK) and commercial-based diamino diphenyl ether (DDE). The universal testing machine and thermogravimetric analyzer) were used to measure the mechanical properties and thermal stability of the cured epoxy samples. The samples’ chemical resistance was assessed by calculating the weight loss in percent after they were submerged in solutions of NaOH, HCl, and NaCl. We also used scanning electron microscopy (SEM) to examine the morphological changes. Rosin-based epoxy cured with imidoamine curing agents outperformed the commercial epoxy in terms of performance.
“…The ECO curing system is different from that of the NBR. Commonly used vulcanizing agents and accelerators include trithiocyanuric acid, ethylene thiourea, lead oxide, calcium oxide, and magnesium oxide 34–42 …”
Low-acrylonitrile nitrile butadiene rubbers (NBRs) are seriously degraded by No. 15 oil in the hydraulic system of aircraft. The present work aims to prepare rubber materials with excellent low-temperature and No. 15 aviation hydraulic oil resistance. Terpolymerization epichlorohydrin rubber (ECO) and lowacrylonitrile NBR were blended. The blends were vulcanized using peroxide.The effects of the ECO/NBR blending ratio on the oil resistance and lowtemperature, physical and mechanical, hot air aging, and ozone aging proper-
“…Bisphenol A diglycidyl ether (DGEBA) diane epoxy resins are widely used thermosets [ 10 ]. Among the biodegradable modifiers for DGEBA are vegetable oils [ 11 , 12 , 13 ], rosin [ 14 , 15 ], lignin, [ 16 ] polylactic acid (PLA) [ 17 ], and in particular, thermoplastic biopolymers of synthetic origin, such as polycaprolactone (PCL).…”
Currently, there is no quantitative approach for the phase structure of cured thermoplastic systems modified with thermoplastic predicting. To solve this problem, we carried out the first stage of the study on a model polycaprolactone–epoxy oligomer (PCL–DGEBA) system. Using differential scanning calorimetry (DSC), refractometry and optical interferometry, a phase diagram for PCL–DGEBA mixtures was constructed, and the Flory–Huggins interaction parameters of PCL–DGEBA mixtures were calculated. The structure of PCL–DGEBA mixtures with different PCL content was analyzed by optical microscopy. The change in the structure formation mechanism with increasing PCL concentration was shown. The diffusion coefficients are calculated by the Motano–Boltzmann method. The values of the apparent activation energy of the viscous flow PCL and of self-diffusion of DGEBA are determined. The obtained data will be used for the in situ curing kinetics and phase equilibria in the diffusion zone investigations in order to develop a quantitative method for predicting the phase structure of cured systems.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
