Biobased composites prepared by compression molding with a novel thermoset resin from soybean oil and a natural‐fiber reinforcement

Biobased composites were manufactured with a compression‐molding technique. Novel thermoset resins from soybean oil were used as a matrix, and flax fibers were used as reinforcements. The air‐laid fibers were stacked randomly, the woven fabrics were stacked crosswise (0/90°), and impregnation was performed manually. The fiber/resin ratio was 60 : 40. The prepared biobased composites were characterized by impact and flexural testing. Scanning electron microscopy of knife‐cut cross sections of the specimens was also done to investigate the fiber–matrix interface. Thermogravimetric analysis of the composites was carried out to provide indications of thermal stability. Three resins from soybean oil [methacrylated soybean oil, methacrylic anhydride modified soybean oil (MMSO), and acetic anhydride modified soybean oil] were used as matrices. The impact strength of the composites with MMSO resin reinforced with air‐laid flax fibers was 24 kJ/m², whereas that of the MMSO resin reinforced with woven flax fabric was between 24 and 29 kJ/m². The flexural strength of the MMSO resin reinforced with air‐laid flax fibers was between 83 and 118 MPa, and the flexural modulus was between 4 and 6 GPa, whereas the flexural strength of the MMSO resin reinforced with woven fabric was between 90 and 110 MPa, and the flexural modulus was between 4.87 and 6.1 GPa. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Thermosets resins prepared from soybean oil and lignin derivatives with high biocontent,superior thermal properties,and biodegradability

A bio-based monomer, methacrylated vanillyl alcohol (MVA), had been synthesized from vanillyl alcohol with methacrylate anhydride (MAA) via a solvent-free, efficient method. The synthesis of MVA was confirmed by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (¹H NMR). It was used to copolymerize with acrylated epoxidized soybean oil (AESO) to prepare a bio-based resin (MVA–AESO). Excess MAA of MVA synthesis was further used to modify AESO with hydroxyl groups, generating (MVA–MAESO) with higher unsaturation degree. Their chemical structure and modification were characterized using ¹³C NMR and Fourier transform infrared analyses. Pure AESO and MVA resins were used to compare with MVA–AESO and MVA–MAESO in terms of their viscosity, curing performance, mechanical, and thermal properties. The synthesized MVA–AESO and MVA–MAESO resins showed much lower viscosities than pure AESO due to the dilution of MVA. In addition, the incorporation of MVA reduced curing temperatures, activation energies which caused MVA–AESO and MVA–MAESO had higher curing degree than pure AESO. With the combination of MVA and modification of MAA, flexible AESO networks exhibited superior flexural properties, storage modulus, glass-transition temperature, and thermal stability. Furthermore, the biodegradation of the formulated bio-based resins were also investigated. Results showed that the addition of monomer and the increase in the content of CC bonds did not significantly affect the biodegradability of AESO, which may be due to the fact that the degradable groups of AESO were not affected. This environmentally friendly, low (volatile organic) resin, prepared by a high efficiency and environmental protection synthetic route, can potentially replace typical petroleum-based thermosets for the production environmentally friendly thermosetting resins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48827.     

Synthesis,characterization, and properties of silicone–epoxy resins

Silicone–epoxy (SiE) resins were synthesized through the hydrolytic condensation of 2‐(3,4‐epoxycyclohexylethyl) methyldiethoxysilane (EMDS) and the cohydrolytic condensation of EMDS with dimethyldiethoxysilane. Structural characterization was carried out by ¹H‐NMR, ²⁹Si‐NMR, and mass spectrometry analysis; the resins were linear oligomers bearing different numbers of pendant epoxy groups, and the average number of repeat Si O units ranged from 6 to 11. Methyhexahydrophthalic anhydride was used to cure the SiE resins to give glassy materials with high optical clarity. The cured SiE resins showed better thermal stability and higher thermal and UV resistances than a commercial light‐emitting diode package material (an epoxy resin named CEL‐2021P). The effect of the epoxy value on the thermal and mechanical properties and the thermal and UV aging performances of the cured SiE resins were investigated. The SiE resins became more flexible with decreasing epoxy value, and the resin with the moderate epoxy value had the highest thermal and UV resistances. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis and Polymerization of Epoxy Methacrylates, 2. Acylated Epoxy Methacrylates and their Copolymers

Partially (20–75%) acylated isopropylidene‐bis[1,4‐phenyleneoxy(2‐hydroxytrimethylene)] dimethacrylate (BisGMA) was prepared by a single step reaction of 2,2‐bis[4‐(2,3‐epoxypropoxy)phenyl]propane (DGEBA) with methacrylic acid (MAA), methacrylic anhydride (MAAn) and/or acetic anhydride catalyzed by 0.8 mol‐% N‐methylimidazole at 90–100°C. In any case, MAA was substituted by an equimolar quantity of the anhydride. The reaction kinetics of DGEBA with MAA and MAAn follows a first order law up to a conversion of epoxy groups corresponding to the initial molar ratio of MAAn. For different mole fractions x_MAA, the reaction rate was found to be directly proportional to x^0.5_MAA. The viscosity of BisGMA decreased with an increase in the acylation degree. Acylated BisGMA was copolymerized with triethylene glycol dimethacrylate (TEGMA) by use of a redox initiator system at room temperature and with vinyltoluene (VT) initiated by di‐tert‐butyl peroxide at 150–200°C, respectively, both in the presence of 70–76 wt.‐% of quartz filler. Different dependencies of the content of sol and the conversion of C=C double bonds were observed for thermally polymerized composites from VT with acetylated and methacrylated BisGMA, respectively. Methacrylated BisGMA yielded composites with reduced water uptake. The higher network density of the polymer matrix with methacrylated BisGMA resulted in a higher glass transition temperature T_g and a higher storage modulus of the composites. The initial temperature of weight loss of composites with VT was increased from 230°C for composites with BisGMA up to 258°C for composites with BisGMA methacrylated to a degree of 40%.     

Synthesis of rosin‐based flexible anhydride‐type curing agents and properties of the cured epoxy

BACKGROUND: Although rosin acid derivatives have received attention in polymer synthesis in recent years, to the best of our knowledge, they have rarely been employed as epoxy curing agents. The objective of the study reported here was to synthesize rosin‐based flexible anhydride‐type curing agents and demonstrate that the flexibility of a cured epoxy resin can be manipulated by selection of rosin‐based anhydride‐type curing agents with appropriate molecular rigidity/flexibility. RESULTS: Maleopimarate‐terminated low molecular weight polycaprolactones (PCLs) were synthesized and studied as anhydride‐type curing agents for epoxy curing. The chemical structures of the products were confirmed using ¹H NMR spectroscopy and Fourier transform infrared spectroscopy. Mechanical and thermal properties of the cured epoxy resins were studied. The results indicate that both the epoxy/anhydride equivalent ratio and the molecular weight of PCL diol play important roles in the properties of cured resins. CONCLUSION: Rosin‐based anhydride‐terminated polyesters could be used as bio‐based epoxy curing agents. A broad spectrum of mechanical and thermal properties of the cured epoxy resins can be obtained by varying the molecular length of the polyester segment and the epoxy/curing agent ratio. Copyright © 2009 Society of Chemical Industry     

Fatty acid‐based comonomers as styrene replacements in soybean and castor oil‐based thermosetting polymers

In this study, a fatty acid‐based comonomer is employed as a styrene replacement for the production of triglyceride‐based thermosetting resins. Styrene is a hazardous pollutant and a volatile organic compound. Given their low volatility, fatty acid monomers, such as methacrylated lauric acid (MLA), are attractive alternatives in reducing or eliminating styrene usage. Different triglyceride‐derived cross‐linkers resins were produced for this purpose: acrylated epoxidized soybean oil (AESO), maleinated AESO (MAESO), maleinated soybean oil monoglyceride (SOMG/MA) and maleinated castor oil monoglyceride (COMG/MA). The mechanical properties of the bio‐based polymers and the viscosities of bio‐based resins were analyzed. The viscosities of the resins using MLA were higher than that of resins with styrene. Decreasing the content of MLA increased the glass transition temperature (T_g). In fact, the T_g of bio‐based resin/MLA polymers were on the order of 60°C, which was significantly lower than the bio‐based resin/styrene polymers. Ternary blends of SOMG/MA and COMG/MA with MLA and styrene improved the mechanical properties and reduced the resin viscosity to acceptable values. Lastly, butyrated kraft lignin was incorporated into the bio‐based resins, ultimately leading to improved mechanical properties of this thermoset but with unacceptable increases in viscosity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

New biobased carboxylic acid hardeners for epoxy resins

Soybean oil was modified into a novel biobased polyacid hardener by thiol‐ene coupling with thioglycolic acid. The structure of the initial soybean oil and polyacid triglyceride was carefully analyzed using ¹H NMR and titration. The thermal crosslinking reaction between acid hardener and epoxidized resin was studied by differential scanning calorimetry (DSC) and rheology. Then, the synthesized biobased acid hardener was employed as a novel curing agent for bisphenol A diglycidyl ether to elaborate new partially biobased materials. These materials, formulated in stoichiometry ratio, were characterized by DSC, thermogravimetry analyses, dynamic mechanical analyses and exhibit interesting properties for coatings. Practical applications: The products of the chemistry described in this contribution, i.e., polyacid from soybean oil and thioglycolic acid, provide biobased building blocks for further epoxy resin syntheses by reaction with epoxy groups. The obtained epoxy resins are partially biobased and may be applied as binders and coatings.     

Soybean and castor oil based monomers: Synthesis and copolymerization with styrene

In this study, castor oil was alcoholyzed with both aliphatic alcohols, such as glycerol and pentaerythritol, and an aromatic alcohol, bisphenol A propoxylate. The resulting alcoholysis products were then malinated and cured in the presence of styrene. Soybean oil pentaerythritol glyceride maleates were also prepared for a direct comparison of the properties of the castor oil and soybean oil based resins. Castor oil was directly malinated as well to see the effect of the alcoholysis step on the properties of the castor oil based resins. The monomers synthesized were characterized by ¹H‐NMR spectroscopy, and the styrenated resin liquid properties, such as viscosity and surface energy values, were determined. The conversion of polymerization was determined using time resolved FTIR analysis for the styrenated soybean oil pentaerythritol glyceride maleates, castor oil maleates, and castor oil pentaerythritol glyceride maleates. The effect of monomer identity and styrene content on the conversion of polymerization was explored. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2433–2447, 2006     

Synthesis and characterization of bio‐based thermosetting resins from lactic acid and glycerol

A bio‐based thermoset resin has been synthesized from glycerol reacted with lactic acid oligomers of three different chain lengths (n): 3, 7, and 10. Lactic acid was first reacted with glycerol by direct condensation and the resulting branched molecule was then end‐functionalized with methacrylic anhydride. The resins were characterized by Fourier‐transform infrared spectroscopy (FT‐IR), by ¹³C‐NMR spectroscopy to confirm the chemical structure of the resin, and by differential scanning calorimetry and dynamic mechanical thermal analysis (DMTA) to obtain the thermal properties. The resin flow viscosities were also measured using a rheometer with different stress levels for each temperature used, as this is an important characteristic of resins that are intended to be used as a matrix in composite applications. The resin with a chain length of three had better mechanical, thermal, and rheological properties than the resins with chain lengths of seven and 10. Also, its bio‐based content of 78% and glass transition temperature of 97°C makes this resin comparable to commercial unsaturated polyester resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40488.     

Flame retardant UV-curable acrylated epoxidized soybean oil based organic–inorganic hybrid coating

Organic–inorganic hybrid coating based on methacrylated/phosphorylated epoxidized soybean oil were obtained by combining photopolymerization and sol–gel process. A series of novel methacrylated and phosphorylated epoxidized soybean oil/silica coating materials were prepared from tetraethoxysilane (TEOS), and acrylated soybean oil via sol–gel technique. Acrylated epoxidized soybean oil (AESO) is obtained by reacting epoxidized soybean oil (ESO) with methacrylic acid and vinyl phosphonic acid. The characterization of AESO was performed by NMR and IR spectroscopy.     

Photolytic and free‐radical polymerization of monomethyl maleate esters of epoxidized plant oil triglycerides

Epoxidized soybean oil (ESO) was reacted with monomethyl maleate with AMC‐2 catalyst. Monomethyl maleate was found to react with 65% of the available epoxy groups to give the monomethyl maleic esters of ESO (MESO). ¹H‐NMR, ¹³C‐NMR, and IR spectra of the new derivative confirmed the proposed structure. The NMR spectra revealed that the average number of monomethyl maleate groups per triglyceride molecule was 2.6. MESO was photopolymerized with ultraviolet light and was free radically homopolymerized and copolymerized with styrene (STY), vinyl acetate (VA), and methylmethacrylate (MMA). MESO was also reacted with maleic anhydride at the newly formed hydroxyl groups to give maleinized MESO, (MESOMA), which now contained 4.9 maleate unsaturations per triglyceride. Dynamic mechanical analysis revealed the dynamic modulus for styrene copolymers of MESO and maleinized MESO as 105 and 140 MPa, respectively. Both of these plant oil derived monomers are good candidates for a practical and economical liquid molding resin. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 626–633, 2007     

Use of eugenol and rosin as feedstocks for biobased epoxy resins and study of curing and performance properties

In this study, an epoxy based on eugenol and an anhydride curing agent based on rosin were prepared. Curing of the eugenol epoxy with a commercial anhydride curing agent and with the rosin‐derived anhydride curing agent was studied. For comparison, a commercial bisphenol A type epoxy, DER353, was also selected in the curing study. The syntheses of the eugenol epoxy and rosin anhydride were investigated and the chemical structures of the products and intermediates were characterized using ¹H NMR and Fourier transform infrared spectroscopies. Non‐isothermal curing of the eugenol epoxy with hexahydrophthalic anhydride and the rosin‐derived maleopimaric acid was studied using differential scanning calorimetry. Thermomechanical properties and thermal stability of the cured epoxy resins were evaluated using dynamic mechanical analysis and thermogravimetric analysis, respectively. Addition of 2‐ethyl‐4‐methylimidazole as catalyst greatly decreased the curing temperature and promoted the completion of cure reactions. The results suggest that the eugenol epoxy and the bisphenol A type epoxy have similar reactivity, dynamic mechanical properties and thermal stability. © 2013 Society of Chemical Industry     

Synthesis and characterization of methacrylated star‐shaped poly(lactic acid) employing core molecules with different hydroxyl groups

A set of novel bio‐based star‐shaped thermoset resins was synthesized via ring‐opening polymerization of lactide and employing different multi‐hydroxyl core molecules, including ethylene glycol, glycerol, and erythritol. The branches were end‐functionalized with methacrylic anhydride. The effect of the core molecule on the melt viscosity, the curing behavior of the thermosets and also, the thermomechanical properties of the cured resins were investigated. Resins were characterized by Fourier‐transform infrared spectroscopy, ¹³C‐NMR, and ¹H‐NMR to confirm the chemical structure. Rheological analysis and differential scanning calorimetry analysis were performed to obtain the melt viscosity and the curing behavior of the studied star‐shaped resins. Thermomechanical properties of the cured resins were also measured by dynamic mechanical analysis. The erythritol‐based resin had superior thermomechanical properties compared to the other resins and also, lower melt viscosity compared to the glycerol‐based resin. These are of desired characteristics for a resin, intended to be used as a matrix for the structural composites. Thermomechanical properties of the cured resins were also compared to a commercial unsaturated polyester resin and the experimental results indicated that erythritol‐based resin with 82% bio‐based content has superior thermomechanical properties, compared to the commercial polyester resin. Results of this study indicated that although core molecule with higher number of hydroxyl groups results in resins with better thermomechanical properties, number of hydroxyl groups is not the only governing factor for average molecular weight and melt viscosity of the uncured S‐LA resins. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45341.     

New polymers from plant oil derivatives and styrene‐maleic anhydride copolymers

In this study, styrene maleic anhydride copolymer (SMA2000, Styrene : Maleic Anhydride 2 : 1) is grafted and/or crosslinked with epoxidized methyl oleate, epoxidized soybean oil, methyl ricinoleate (MR), castor oil (CO), and soybean oil diglyceride. Base catalyzed epoxy‐anhydride and alcohol‐anhydride polyesters were synthesized by using the anhydride on SMA, the epoxy or secondary alcohol groups on the triglyceride based monomers. The characterizations of the products were done by DMA, TGA, and IR spectroscopy. SMA‐epoxidized soy oil and SMA‐CO polymers are crosslinked rigid infusible polymers. SMA‐epoxidized soy oil and SMA‐CO showed T_g's at 70 and 66°C, respectively. Dynamic moduli of the two polymers were 11.73 and 3.34 Mpa respectively. SMA‐epoxidized methyl oleate, poly[styrene‐co‐(maleic anhydride)]‐graft‐(methyl ricinoleate), and SMA‐soy oil diglyceride polymers were soluble and thermoplastic polymers and were characterized by TGA, GPC, DSC, NMR, and IR spectroscopy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Hydroxymethylation and polymerization of plant oil triglycerides

The ene reaction between plant oil triglycerides (such as soybean and sunflower oils) and paraformaldehyde was used to introduce a homoallylic hydroxyl functionality on the triglyceride. Paraformaldehyde and triglyceride were reacted in the presence of a Lewis acid catalyst, ethylaluminum dichloride, and hydroxymethyl derivatives were obtained at yields of 42 and 55% for sunflower oil and soybean oil, respectively. In the next step, hydroxymethyl products were reacted with maleic anhydride at 100°C to produce the maleate half esters. The average number of maleate groups per triglycerides was found to be 1.7 for soybean oil and 1.3 for sunflower oil. In the final step, the free‐radical–initiated copolymerization of the maleinized triglycerides with styrene produced rigid polymers. Characterization of new monomers and polymers was done by ¹H‐NMR, ¹³C‐NMR, and infrared and mass spectrometries. The swelling behavior of the crosslinked network polymers was determined in different solvents. The glass‐transition temperature of the cured resin was also determined by differential scanning calorimetry to be 40°C for soybean‐based polymer and 30°C for sunflower‐based polymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 4037–4046, 2004     

Functionalization of a multiepoxy resin by methacrylic compounds and study of its thermal properties

Summary Methacrylation of triglycidyl triphenyl methane (via methacrylic acid) has been done using three catalysts: dimethyl dodecyl amine (DMDA), tetrabutyl ammonium bromide (TBAB) and chromium (III) diisopropyl salicylate (Cr Dips). The reaction has been followed by epoxy colorimetric titration, CPG and ¹H NMR.This study has shown the superiority of chromium catalysis because of its rapidity and ease of process.Then, these cured products (TACTIX and methacrylated TACTIX) show homogeneous Tg values which are higher than 200°C.     

Synthesis,spectral, and thermal characterization of photoreactive epoxy resin containing cycloalkanone moiety in the main chain

Dual functional epoxy resins were synthesized by solution polycondensation of 2,6‐bis(4‐hydroxy‐3‐methoxy benzylidene)cyclohexanone and 2,5‐bis(4‐hydroxy‐3‐methoxy benzylidene)cyclopentanone with epichlorohydrin. The synthesized epoxy resins were characterized systematically for their structure by UV, Fourier transform infrared (FTIR), ¹H NMR, and ¹³C NMR spectroscopic techniques. Thermal characterization of synthesized epoxy resins was carried out by thermogravimetric analysis, and differential scanning calorimetry (DSC) under nitrogen atmosphere. The self extinguishing property of synthesized oligomers was studied by determining limiting oxygen index (LOI) values using Van Krevelen's equation. X‐ray analysis showed that the epoxy resins containing cyclopentanone have higher degree of crystallinity. The photoreactive property of the synthesized epoxy resins in solution and film states was investigated by UV–Vis spectroscopy. The photocross‐linking proceeds through the dimerization of olefinic chromophore present in the main chain of the oligomer via 2π + 2π cycloaddition reaction. The influence of photoacid generator on the rate of photocross‐linking of epoxy resin was studied by FTIR. UV irradiation of the epoxy resin in presence of photoacid generator produces aromatic sulfonium cation radicals and aromatic radicals which initiate the cationic ring‐opening polymerization of oxirane ring. The photoreactivity studies of the oligomers by FTIR and DSC indicated the presence of dual functionality in the synthesized epoxy resins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and antitumour and antiangiogenesis activity of polymers containing methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid

A new monomer, methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid (MTCA), was synthesized from citric acid and methacrylic anhydride. Poly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid) and poly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid)‐co‐(maleic anhydride) were prepared by radical polymerizations. Terpoly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid–maleic anhydride–furan) was obtained by in situ terpolymerization of MTCA and exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalic anhydride. The synthesized samples were identified by FTIR, ¹H NMR and ¹³C NMR spectroscopies. The number‐average molecular weights of the fractionated polymers determined by GPC were in the range 14 900–16 600 and polydispersity indices were less than 1.14. The in vitro IC₅₀ values of the monomer and polymers against cancer and normal cell lines were much higher than those of 5‐fluorouracil (5‐FU). The in vivo antitumour activities of the synthesized samples at a dosage of 0.8 mg kg⁻¹ against mice bearing the sarcoma 180 tumour cell line decreased in the order terpoly(MTCA‐MAH‐FUR) > poly(MTCA‐co‐MAH) > poly(MTCA) > MTCA > 5‐FU. The synthesized samples inhibited DNA replication and angiogenetic activity more than did 5‐FU. © 2001 Society of Chemical Industry     

Synthesis of a novel curing agent containing organophosphorus and its application in flame‐retarded epoxy resins

A novel amine‐terminated and organophosphorus‐containing compound m‐aminophenylene phenyl phosphine oxide oligomer (APPPOO) was synthesized and used as curing and flame‐retarding agent for epoxy resins. Its chemical structure was characterized by Fourier transform infrared (FTIR) spectroscopy, ¹H nuclear magnetic resonance (¹H NMR), ¹³C nuclear magnetic resonance, and ³¹P nuclear magnetic resonance. The flame‐retardant properties, combusting performances, and thermal degradation behaviors of the cured epoxy resins were investigated by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter test, and thermogravimetric analysis. The EPO/APPPOO thermosets passed V‐1 rating with the thickness of 3.0 mm and the LOI value reached 34.8%. The thermosets could pass V‐2 rating when the thickness of the samples was 1.6 mm. The cone calorimeter test demonstrated that the parameters of EPO/APPPOO thermosets including heat release rate and total heat release significantly decreased compared with EPO/PDA thermosets. Scanning electron microscopy revealed that the incorporation of APPPOO into epoxy resins obviously accelerated the formation of the compact and stronger char layer to improve flame‐retardant properties of the cured epoxy resins during combustion. The mechanical properties and water resistance of the cured epoxy resins were also measured. After the water‐resistance test, EPO/APPPOO thermosets still remained excellent flame retardant and the water uptake was only 0.4%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41159.     

Polymerization reactions of epoxidized soybean oil and maleate esters of oil‐soluble resoles

In this study, the polymerization reactions of epoxidized soybean oil (ESO) with the maleate half‐esters of oil‐soluble resoles and the properties of the final products were demonstrated. The maleate half‐esters of the dimeric oil‐soluble resoles were obtained by the esterification reaction of maleic anhydride with a p‐tertiary butyl phenol (p‐TBP) resole and p‐nonyl phenol resole resins in the first step. The monomers were characterized by IR and ¹H‐NMR techniques. Then, the oil‐soluble resole maleates were polymerized with ESO to obtain tough and load‐bearing thermoset materials. The thermal and mechanical properties of the materials were determined by dynamic mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, and tensile strength testing. The tensile strengths and storage moduli of the crosslinked polymers varied between 0.17 and 13 MPa and 10 and 1088 MPa, respectively. The elongation percentages of the materials were between 1 and 128%. The thermal resistance of the thermosets was measured as the 5% weight loss temperature. The reaction product of the ESO and maleate ester of p‐TBP showed the highest 5% weight loss at 247°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41457.