Trifunctional Epoxy Research Articles

Thymol-Derived Trifunctional Epoxy Novolac from Controllable Synthesis to Performance-Advantaged Thermosets

Thymol-Derived Trifunctional Epoxy Novolac from Controllable Synthesis to Performance-Advantaged Thermosets

Advanced fabrication and characterization of AMMT nano clay reinforced tri-functional epoxy nanocomposites for superior thermal and mechanical properties

Advanced fabrication and characterization of AMMT nano clay reinforced tri-functional epoxy nanocomposites for superior thermal and mechanical properties

Innovative phosphorus-containing epoxy resins: A new approach to acidic corrosion protection

The main challenges in the corrosion field for steel include its high susceptibility to acidic degradation and the need for sustainable and efficient corrosion inhibitors. The main objective was to synthesize a novel phosphorus-containing trifunctional epoxy resin, named phosphoric ester triglycidyl ether hydroquinone (TGEHEP), through a two-step process. Initially, the intermediate known as phosphoric ester trihydroquinone was synthesized. Subsequently, epichlorohydrin was added in the second step to produce the new TGEHEP epoxy resin. For the structural characterization of this compound, FTIR, 1H and 13C NMR were used. These techniques confirmed the final chemical structure of the synthesized macromolecule. The newly developed TGEHEP epoxy resin was subsequently utilized as a protective agent for carbon steel in 1.0 M HCl. This study incorporated various techniques, including PDP, EIS, EFM, DFT, MC, and MD simulations. Additionally, SEM/EDS was applied to examine the surface. These methods allowed us to analyse the surface structure and chemical composition of the sample, providing further insights into the adsorption process and corrosion protection mechanism. Electrochemical test results revealed that the TGEHEP concentration significantly enhanced protection. Notably, EIS demonstrated an outstanding protection efficiency of 96.70% with 10−3 M TGEHEP epoxy resin. The polarization findings also indicate that the resin acts as a mixed inhibitor. In line with the Langmuir isotherm, epoxy resin was effectively used to protect the metal surface. Furthermore, thermodynamic kinetic parameters were estimated to evaluate the adsorption of the inhibitor. TGEHEP showed a greater adsorption energy (-195.05 kcal/mol) than did its protonated form (-178.65 kcal/mol), indicating that the interaction with the iron surface was stronger in its neutral form. A significant increase in the concentration of TGEHEP was detected, reaching a maximum of 762.4 Ω.cm² at a concentration of 10−3 M. This suggests that TGEHEP forms a barrier that impedes electron transfer, a key factor in corrosion processes. The ΔGads is −44.3 kJ/mol, which is within the typical range for chemisorption. This suggests that the adsorption of TGEHEP onto the metal surface includes more than just physical adsorption; it likely involves electron transfer, which is characteristic of a chemisorptive bond. Comparatively, TGEHEP demonstrates superior performance to previously published corrosion inhibitors, with its efficacy not only attributed to its unique chemical structure but also to its environmentally benign nature.

Thymol-Derived Trifunctional Epoxy Resin with Outstanding Thermomechanical Properties and Low Dielectric Constant: From High-Throughput Synthesis to High-Performance Thermoset

Thymol-Derived Trifunctional Epoxy Resin with Outstanding Thermomechanical Properties and Low Dielectric Constant: From High-Throughput Synthesis to High-Performance Thermoset

Synthesis, Curing Behaviors and Properties of a Bio-Based Trifunctional Epoxy Silicone Modified Epoxy Thermosets.

Tremendous effort has been focused on improving the toughness of epoxy, but the common approaches diminish the mechanical properties. In this work, a new silicone-modified trifunctional epoxy monomer SITEUP is synthesized from the hydrosilylation transformation of eugenol epoxy (EPEU) and tris-(dimethylsiloxy)phenylsilane. The chemical structures and curing kinetics of SITEUP are investigated based on 1H-NMR, 13C-NMR, MADLI-TOF-MS, and DSC analyses. SITEUP is introduced into DGEBA/IPDA systems as a functional modifier in varied loadings for toughening the resulting epoxy thermosets. The impact strength of the modified epoxy thermosets containing 20% SITEUP is 84% higher than that of the pristine epoxy thermoset and also maintains high flexural strength. Further morphology study reveals that the plastic deformation caused by siloxane segments is the key factor accounting for the enhanced toughness of the finalized epoxy thermosets. Si-O-Si segments incorporated into the thermosetting network could absorb more energy by increasing the mobility of polymer chains under external stress and led to improved thermal stability and damping characteristics. In addition, SITEUP is able to decrease the surface tension and increase the hydrophobic properties of the resultant epoxy materials.

Self-toughening of epoxy resin by introduction of highly crosslinked thermoset epoxy microspheres

The theories and technologies concerning polyolefin toughening with rubber or inorganic rigid particle have been studied comprehensively, the results indicated that the toughening with rubber always lowers the modulus and heat resistance of materials. Also, toughening with inorganic rigid particle is not good because of its low dispersion and miscibility with epoxy resin. Monodisperse epoxy microspheres (EMs) with high crosslinking density were prepared with Polypropylene glycol with molecular weight of 600 as the reaction solvent and trifunctional epoxy resin (TDE-85) and aromatic diamine (DETDA) as the precursors. The formation of EMs was investigated in detail. The crosslinked microspheres were used as toughening agent to realize DGEBA/DDS system self- toughening. When adding 5wt% epoxy microspheres, the impact strength improved by 87% and Tg increased more than 6 °C. The results show that the prepared epoxy microspheres with high crosslinking density can not only greatly improve the toughness of epoxy resin, but also improve its heat resistance.

Influences of Modified Sm2O3 on Thermal Stability, Mechanical and Neutron Shielding Properties of Aminophenol Trifunctional Epoxy Resin.

The requirements regarding the weight and capacity reduction of neutron shielding materials have become an urgent issue for advanced nuclear facilities and plants. An epoxy-based neutron shielding material with high-temperature stability and good neutron irradiation resistance was designed in this paper to solve the above issue. Aminophenol trifunctional epoxy resin (AFG-90H) was compounded with samarium oxide (Sm2O3) by means of an ultrasonic-assisted method and the compatibility of Sm2O3 with the AFG-90H matrix was improved by 3-aminopropyltriethoxysilane (APTES) surface modification. Fabricated Sm2O3-APTES/AFG-90H composites exhibited improved thermal stability, glass transition temperature and Young’s modulus with increased Sm2O3-APTES content. Neutronics calculation results show that the neutron permeability of 2 mm-thick 30 wt% Sm2O3-APTES/AFG-90H was 98.9% higher than that of the AFG-90H matrix under the irradiation of the thermal neutron source. The results show that the proper addition range of Sm2O3-APTES is between 20% and 25%. The Sm2O3-APTES/AFG-90H composite is a promising neutron shielding material for advanced nuclear system.

Synthesis of a curing agent containing trifunctional epoxy groups for powder coatings and its curing reaction kinetics

Synthesis of a curing agent containing trifunctional epoxy groups for powder coatings and its curing reaction kinetics

Thermal, mechanical, and electrical properties of difunctional and trifunctional epoxy blends with nanoporous materials

In the present study, the aim is to synthesize the particulate nanocomposites with difunctional and trifunctional epoxy blend as matrix and synthesized nanoporous materials as fillers. Organic/inorganic hybrid networks were prepared by the novel solvent free method. Viscoelastic, thermal, and electrical properties of di- and trifunctional epoxy and the effect of different nanoparticles in the particulate nanocomposites have been studied by dynamic mechanical analyzer, thermogravimetry (TGA), and dielectric strength. Epoxy mixed with different compositions of TGPAP and particulate nanocomposites by the addition of different types of nanomaterials shows higher storage modulus than the pure epoxy. The addition of TGPAP and nanofillers decreases the thermal stability of epoxy matrix. The evolved gas analysis (TG-FTIR) was also done in order to study the products formed during degradation. An increase in dielectric strength and impact strength (4%) was also observed in the particulate nanocomposites.

Stilbene 구조를 지닌 바이오 기반 에폭시 열경화성 수지의 높은 T<SUB>g</SUB> 및 난연성

Bio-based epoxy resins with an ultrahigh glass transition temperature (T<SUB>g</SUB>) and excellent flame retardancy are critical for developing sustainable polymers. Herein, a novel trifunctional epoxy monomer triglycidyl ether of resveratrol (TGER) was synthesized from renewable resveratrol. The chemical structure of TGER was confirmed by Fourier transform infrared (FTIR), ¹H, and <SUP>13</SUP>C nuclear magnetic resonance (NMR) spectroscopy which was then reacted with 4,4’-diaminodiphenylmethane (DDM) to form resin. The obtained resin was evaluated in terms of flame retardance and thermal properties. The resultant TGER-DDM 240 resin shows excellent flame-retardant properties, presenting a residual char of 42.5% at 800 ℃, limiting oxygen index (LOI) of 31.2%, and flammability rating of V-0 in UL94 test. Moreover, the resin possesses an ultrahigh T<SUB>g</SUB> at 294 ℃. This work provides a facile method for preparing high-performance flame-retardant epoxy resin from a renewable resource.

Studies on the Modification of Commercial Bisphenol-A-Based Epoxy Resin Using Different Multifunctional Epoxy Systems

The tensile fracture mechanics and thermo-mechanical properties of mixtures composed of two kinds of epoxy resins of different chemical structures and functional groups were studied. The base resin was a bi-functional epoxy resin based on diglycidyl ether of bisphenol-A (DGEBA) and the other resins were (a) distilled triglycidylether of meta-amino phenol (b) 1, 6–naphthalene di epoxy and (c) fluorene di epoxy. This research shows that a small number of multifunctional epoxy systems, both di- and tri-functional, can significantly increase tensile strength (14%) over neat DGEBA while having no negative impact on other mechanical properties including glass transition temperature and elastic modulus. In fact, when compared to unmodified DGEBA, the tri-functional epoxy shows a slight increase (5%) in glass transition temperature at 10 wt.% concentration. The enhanced crosslinking of DGEBA (90 wt.%)/distilled triglycidylether of meta-amino phenol (10 wt.%) blends may be the possible reason for the improved glass transition. Finally, the influence of strain rate, temperature and moisture were investigated for both the neat DGEBA and the best performing modified system. The neat DGEBA was steadily outperformed by its modified counterpart in every condition.

Shape memory epoxy vitrimers based on waste frying sunflower oil

AbstractThermoset polyesters are prepared from epoxidized waste frying sunflower oil (ESO), commercially available epoxy compounds and glutaric acid. Influence of the nature and concentration of bi‐ and trifunctionnal epoxy compounds on mechanical properties is studied. Static and dynamic mechanical tests are performed. The molar amount of commercial epoxy compounds used ranges from 20% to 80% regarding the molar amount of ESO. It enables to obtain thermosetting polyesters with glass transition temperatures ranging from 6°C to 102°C, as well as storage modulus ranging from 8 GPa to 14 GPa. 40% of trifunctional epoxy compound and 60% of commercial epoxy compound are found to be the best compromises between bio‐based content and mechanical properties. Furthermore, shape memory and vitrimer behavior of those epoxy‐acid based networks with 60% of commercial epoxy compounds are evaluated both qualitatively and quantitatively by cyclic thermo‐mechanical and stress relaxation tests. Excellent shape memory behavior with fixity ratios above 94% and recovery ratios above 98% is demonstrated. A transesterification catalyst is needed to obtain good vitrimer behavior. Overall, thanks to the previously mentioned properties of those partially biobased thermosets polyesters, industrial applications such as protective coatings, foams and temperature‐memory polymer actuators might be considered.

One-pot Synthesis of Trifunctional Epoxy Resin and its Nanocomposite: Investigation of Thermal and Rheological Properties

Herein, in the present study, we developed the synthesis of new trifunctional epoxy resin (TER) namelytriglycidyl ether N,N bis (3-phenylamino propyl) 3-phenylamino propoxy phenyl and the elaboration of its nanocomposite. TER was characterized and confirmed using Fourier transform infrared and nuclear magnetic resonance spectroscopy. Further, the storage modulus and loss modulus for all formulated nanocomposite increase with the increase in the zinc oxide filler. The results of the thermogravimetric analysis confirm the amelioration in the thermal properties of different nanocomposites TER/MDA/ZnO crosslinked by methylene dianiline (MDA) and formulated by zinc oxide (ZnO) as a filler at varying mass percentage (0, 0.5, 1, and 2%).

Build-To-Specification Vanillin and Phloroglucinol Derived Biobased Epoxy-Amine Vitrimers.

Epoxy resins are widely used in the composite industry due to their dimensional stability, chemical resistance, and thermo-mechanical properties. However, these thermoset resins have important drawbacks. (i) The vast majority of epoxy matrices are based on non-renewable fossil-derived materials, and (ii) the highly cross-linked molecular architecture hinders their reprocessing, repairing, and recycling. In this paper, those two aspects are addressed by combining novel biobased epoxy monomers derived from renewable resources and dynamic crosslinks. Vanillin (lignin) and phloroglucinol (sugar bioconversion) precursors have been used to develop bi- and tri-functional epoxy monomers, diglycidyl ether of vanillyl alcohol (DGEVA) and phloroglucinol triepoxy (PHTE) respectively. Additionally, reversible covalent bonds have been incorporated in the network by using an aromatic disulfide-based diamine hardener. Four epoxy matrices with different ratios of epoxy monomers (DGEVA/PHTE wt%: 100/0, 60/40, 40/60, and 0/100) were developed and fully characterized in terms of thermal and mechanical properties. We demonstrate that their performances are comparable to those of commonly used fossil fuel-based epoxy thermosets with additional advanced reprocessing functionalities.

Comparative studies on carbon fiber reinforced composites based on trifunctional epoxy resin and commercial epoxy resin

The present work focuses on comparative properties of β-naphthol based trifunctional epoxy resin and commercial epoxy resin. Reaction of β-naphthol, formaldehyde and epichlorohydrin forms trifunctional epoxy resin. β-Naphthol based trifunctional epoxy resin characterized by FT-IR, elemental analysis (C, H, N, O analyzer), epoxy equivalent weight (EEW), weight average molecular weight [Formula: see text], viscosity, rise in viscosity, hydrolysable chlorine content and volatile content. β-Naphthol based trifunctional epoxy resin cured by five different hardeners and used as matrix material for carbon reinforced composites. Composites were characterized by their mechanical properties, chemical resistance and thermal properties. Results showed excellent chemical and thermal resistance. All results were compared against commercially available epoxy resin (Diglycidyl ether of bisphenol-A based epoxy resin having EEW of 400). Results showed that β-naphthol based trifunctional epoxy resin was superior than commercial epoxy resin.

Trifunctional epoxy resin as anticorrosive material for carbon steel in 1 M HCl: Experimental and computational studies

In this study, inhibition effect of a trifunctional epoxy resin (designated as TGEAP) on carbon steel (CS) corrosion is evaluated using different techniques. Electrochemical demonstrations showed that TGEAP showed optimum efficiency of 90 % at 10−3M concentration. Mixed- and interface-type behaviour of TGEAP was confirmed by polarization and electrochemical impedance spectroscopic (EIS) studies, respectively. Effect of temperature on anticorrosive effect of TGEAP was also studied and results showed that decrease in the protection efficiency was observed with rise in the temperature. Computational modelings analyses were adopted to describe the interactions between metallic surface and TGEAP molecules. Results showed that TGEAP interacts through donor-acceptor interactions and acquires nearly flat orientation on metallic surface.

Eugenol-derived reconfigurable high-performance epoxy resin for self-deployable smart 3D structures

Fabricating biobased reconfigurable high performance epoxy resins for self-deployable 3D smart structures is an interesting issue with great challenge. Herein, a biobased trifunctional epoxy monomer (tris(2-methoxy-4-(oxiran-2-ylmethyl)phenyl) phosphate, TMOPP) was derived from eugenol and cured by 4,4′-dithiodianiline (DTDA) to form the dynamic cross-linked TMOPP/DTDA resin. The integrated properties including thermal, mechanical and flame retardancy of TMOPP/DTDA resin are studied systemically. Compared with commercial epoxy resin (diglycidyl ether of bisphenol A (DGEBA)/DTDA), TMOPP/DTDA resin has higher glass transition temperature (217 °C) and tensile strength (95.2 MPa), while these properties are superior to those of biobased dynamic cross-linked epoxy resins reported in literatures. TMOPP/DTDA resin also shows excellent flame retardancy with UL-94 V-0 rating. The trifunctional aromatic structure of TMOPP and the compact cross-linked structure of TMOPP/DTDA resin play a principle role in the outstanding performances. At the same time, permanent shape reconfigurability and self-deployable ability of TMOPP/DTDA resin was exhibited by the transformation from planar film into a 3D “rocking chair” structure. These results provide a new method to produce biobased reconfigurable high performance epoxy resin in a simple and sustainable way, while expand the application of dynamic cross-linked epoxy resins in self-deployable 3D smart structures.

Vanillin-derived epoxy monomer for synthesis of bio-based epoxy thermosets: effect of functionality on thermal, mechanical, chemical and structural properties

Tri-functional vanillin-derived epoxy monomer was developed through the synthesized di-functional reagent and cured with a series of different types of hardeners (hydroxyl and amine based) to evaluate thermo-mechanical properties of the resultant epoxy thermosets. Through elevating of curing degree by the hardeners, both alpha transition temperature (Tα) and cross-linking density (υ) slightly increased (up to 118 °C and 69.9 mol m−3). However, the highest values of storage and loss modulus (E′ and E″, respectively) were obtained using trimethylolpropane (TMP) in epoxy thermoset systems cooperating with tri-functional epoxy monomer at 3200 MPa and 359.3 MPa, respectively. The sample produced by TMP exhibited the highest amount of statistic heat-resistant index (Ts) (up to 193 °C). Nevertheless, the longest half-life and the highest Td are obtained for the sample prepared by incorporation of tris(hydroxymethyl)aminomethane (TRIS) and 1,10-diaminodecane (1347 s, 431 °C, respectively) containing amine agents as curing agent. Remarkably, the sample comprising triethanol amine showed the highest char yield (3.3 mg at 700 °C) among the all samples. However, the sample cured by TRIS exhibited the highest elasticity, elongation and tensile strength among the obtained samples (up to 0.48 GPa, 6.56% and 22.90 MPa, respectively).

Trifunctional epoxy polymer as corrosion inhibition material for carbon steel in 1.0 M HCl: MD simulations, DFT and complexation computations

Performance of trifunctional epoxy polymer namely triglycidyl ether tribisphenol A of ethylene (TGETBAE) as corrosion inhibition for carbon steel in 1.0 M HCl solution was evaluated using experimental (weight loss (WL), electrochemical impedance spectroscopy (EIS), UV–Visible spectroscopy and scanning electron microscope (SEM)) and computational (molecular dynamics (MD) simulations, density functional theory (DFT) and complexation calculations) approaches. The applied techniques (WL and EIS) reveal that the inhibition efficiencies of 10−3 M of TGETBAE reach a maximum of 87.7% and 93% at 298 K, respectively. TGETBAE inhibited the metal corrosion through adsorption mechanism that can be explained using the Langmuir adsorption isotherm. The theoretical studies are in good agreement with experimental results.

Thermal Stability and Flame Retardancy of a Cured Trifunctional Epoxy Resin with the Synergistic Effects of Silicon/Titanium

An amino curing agent containing silicon/titanium flame-retardant elements (STCA) based on (3-aminopropyl)triethoxysilane (APTES) and tetrabutyl titanate was successfully prepared. The thermal decomposition and flame-retardant properties of a STCA-cured trifunctional epoxy resin, which was facilely synthesized by 1,1,1-tris(4-hydroxyphenyl)ethane and epichlorohydrin via a two-step method, were compared with those of another amino curing agent containing silicon (SCA) based on APTES and methyltrimethoxysilane. The structures of STCA and SCA were characterized by Fourier transform infrared (FT-IR), 29Si NMR, and Raman spectroscopies. The STCA-cured thermoset not only had good thermal stability with an initial decomposition temperature of 344.8 °C and a char yield of 52.7% at 800 °C but also exhibited the overall improvement of flame-retardant properties. V-0 rating was achieved using the UL-94 test, and the value of limiting oxygen index reached 33.8%. From the thermogravimetry–infrared test, the yield of pyrolysis products of the STCA-cured thermoset was significantly decreased, indicating the lower toxicity in contrast to the SCA-cured thermoset. Flame-retardant performances were also investigated using the cone calorimetry test, and the flame retardancy mechanism was studied using scanning electron microscopy, FT-IR, and energy-dispersive spectrometry. The results indicate that the introduction of silicon/titanium to the system reveals the synergistic effects to promote the formation of an intumescent, sufficient, and compact char layer during combustion, which could effectively prevent heat, oxygen, and flame from penetrating into the interior structure, and lead to the retardance of further combustion.