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     

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     

Soybean Oil-Based Polyurethane Networks: Shape-Memory Effects and Surface Morphologies

Vegetable oil‐based shape‐memory polyurethane networks are an emerging class of bio‐based functional materials with great potential applications. In this study, a series of different structural soybean oil polyols were synthesized, and utilized to fabricate polyurethane networks by reacting with 1,6‐diisocyanatohexane. The soybean oil‐based polyurethanes (SOPUs) were characterized with differential scanning calorimetry (DSC), dynamic mechanical tests (DMA), tensile testing, shape‐memory testing, and atomic force microscopy (AFM). It was found that SOPUs with a preserved triglyceride structure were fixed in a temporary shape at ?20 °C, while others were fixed in temporary shapes at 4 °C. Although the recovery speeds were different, all the samples could completely regain their permanent shapes at 37 °C (human body temperature). Furthermore, different SOPUs exhibited different surface structures, which might provide the materials with additional values.     

Tris(trimethylsilyl)methyl functionalized 4‐chloromethyl styrene polymers: Effects of side chain modification on polymer structure and glass transition temperature

4‐Chloromethyl styrene was copolymerized with various molar ratio of methyl methacrylate or ethyl methacrylate by solution free radical polymerization method, at 70 ± 1°C using α,α′‐azobis(isobutyronitrile) as an initiator. Then, very highly sterically hindered tris(trimethylsilyl)methyl substituent was covalently linked to the obtained copolymers with liberation of chlorine atoms. The structure of all polymers was characterized and confirmed by FT‐IR, ¹H and ¹³C NMR spectroscopy techniques. The average molecular weight and glass transition temperature of polymers were determined using gel permeation chromatograph and differential scanning calorimeter instruments, respectively. Study of differential scanning calorimetry analyses showed that chemical modification of 4‐chloromethyl styrene copolymers with tris(trimethylsilyl)methyl substituents leads to an increase in the rigidity and glass transition temperature of polymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 633–639, 2006     

Synthesis of poly(epichlorohydrin‐g‐methyl methacrylate) and poly(epichlorohydrin‐g‐styrene) graft copolymers by a combination of cationic and photopolymerization methods

Poly(epichlorohydrin‐g‐styrene) and poly (epichlorohydrin‐g‐methyl methacrylate) graft copolymers were synthesized by a combination of cationic and photoinitiated free‐radical polymerization. For this purpose, first, epichlorohydrin was polymerized with tetrafluoroboric acid (HBF₄) via a cationic ring‐opening mechanism, and, then, polyepichlorohydrin (PECH) was reacted ethyl‐hydroxymethyl dithio sodium carbamate to obtain a macrophotoinitiator. PECH, possessing photolabile thiuram disulfide groups, was used in the photoinduced polymerization of styrene or methyl methacrylate to yield the graft copolymers. The graft copolymers were characterized by ¹H‐NMR spectroscopy, differential scanning calorimetry, and gel permeation chromatography. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

New soybean oil–styrene–divinylbenzene thermosetting copolymers. I. Synthesis and characterization

The cationic copolymerization of regular soybean oil, low‐saturation soybean oil (LoSatSoy oil), or conjugated LoSatSoy oil with styrene and divinylbenzene initiated by boron trifluoride diethyl etherate (BF₃·OEt₂) or related modified initiators provides viable polymers ranging from soft rubbers to hard, tough, or brittle plastics. The gelation time of the reaction varies from 1 × 10² to 2 × 10⁵ s at room temperature. The yields of bulk polymers are essentially quantitative. The amount of crosslinked polymer remaining after Soxhlet extraction ranges from 80 to 92%, depending on the stoichiometry and the type of oil used. Proton nuclear magnetic resonance spectroscopy and Soxhlet extraction data indicate that the structure of the resulting bulk polymer is a crosslinked polymer network interpenetrated with some linear or less‐crosslinked triglyceride oil–styrene–divinylbenzene copolymers, a small amount of low molecular weight free oil, and minor amounts of initiator fragments. The bulk polymers possess glass‐transition temperatures ranging from approximately 0 to 105°C, which are comparable to those of commercially available rubbery materials and conventional plastics. Thermogravimetric analysis (TGA) indicates that these copolymers are thermally stable under 200°C, with temperatures at 10% weight loss in air (T₁₀) ranging from 312 to 434°C, and temperatures at 50% weight loss in air (T₅₀) ranging from 445 to 480°C. Of the various polymeric materials, the conjugated LoSatSoy oil polymers have the highest glass‐transition temperatures (T_g) and thermal stabilities (T₁₀). The preceding properties that suggest that these soybean oil polymers may prove useful where petroleum‐based polymeric materials have found widespread utility. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 658–670, 2001     

Ecofriendly Autoxidation of Castor Oil/Ricinoleic Acid. Multifunctional Macroperoxide Initiators for Multi Block/Graft Copolymers

Ecofriendly autoxidation is a reaction of air oxygen with unsaturated organic molecules at room temperature. Castor oil and ricinoleic acid were ecofriendly autoxidized for 5 months to obtain castor oil macroperoxide with a Mn of 1935 g mol⁻¹ (Pcast5m) and the ricinoleic acid macroperoxide initiator (Prici5m) with a Mn of 1169 g mol⁻¹. Peroxide groups thermally initiated the free radical polymerization of methyl methacrylate (MMA), n-butyl methacrylate (nBMA), and styrene (S). Peroxide formation in the oxidized castor oil and ricinoleic acid was confirmed using iodometric analysis, elemental analysis, and differential scanning calorimetry technique. Peroxide decomposition in both macroperoxide initiators was observed at 166 °C for Prici5m and 170 °C for Pcast5m. Hydroxyl groups of Pcast5m were reacted with methacryloyl chloride to obtain methacrylated castor oil macroperoxide (PcastMA). The polymerization rates of the obtained macroinitiators were compared. The polymerization rate order is Pcast5m > Prici5m > PcastMA. Polymerization of styrene by PcastMA resulted in an increase in molar masses and an increase in the polymerization time while those of the styrene polymerization by Pcast5m and Prici5m remained constant. Carboxylic acid groups were reacted with amine-terminated polyethylene glycol (PEG), polydimethyl siloxane (PDMS), and polytetrahydrofuran (PTHF) while the hydroxyl functionality initiated the ring-opening polymerization of ε-caprolactone (CL). Prici-PEG-PMMA, Prici-PS-PDMS, Prici-PS-PTHF, Pcast-PS-PCL, Pcast-PCL-PMMA, and Pcast-PS-PnBMA multiblock copolymers were prepared and characterized using spectrometric, thermal, and stress–strain measurement techniques.     

Synthesis and polymerization of the bromoacrylated plant oil triglycerides to rigid,flame‐retardant polymers

Simultaneous addition of bromine and acrylate to the double bonds of fatty acids in triglycerides was achieved. In the first part of the study, methyl oleate was bromoacrylated in the presence of acrylic acid and N‐bromosuccinimide as a model compound for the application of the reaction to the triglycerides. Next, soybean oil and high oleic sunflower oil were bromoacrylated by using the same procedure. The products were characterized by GC, IR, ¹H‐NMR, ¹³C‐NMR, and mass spectrometry. The bromoacrylation yields for soybean oil and sunflower oil were 75 and 55%, respectively. A rigid thermoset polymer was prepared from the radical copolymerization of bromoacrylated soybean oil with styrene. The bromoacrylated sunflower oil–styrene copolymer showed semirigid properties. The crosslinked network structure of the copolymers was examined by their swelling behavior in different solvents. Glass‐transition temperatures were also determined and soybean oil–based polymer and sunflower oil–based polymer showed a glass transition at 55–65 and 20–30°C, respectively. The storage moduli of the soybean‐based and sunflower‐based polymers at room temperature were approximately 1.0 × 10¹⁰ and 1.1 × 10⁸ Pa, respectively. Photopolymerization was also carried out by using 2,2‐dimethoxy‐2‐phenyl‐acetophenone as initiator. The response of the cured polymers to the thermal energy produced by a small flame was also tested by the ignition respond index method according to ASTM D 3713‐78 and was found to be 5 B at 2.00 mm. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91:2700–2710, 2004     

Synthesis and polymerization of the acrylamide derivatives of fatty compounds

The Ritter reaction of plant oil triglycerides (such as soybean and sunflower oil) with acrylonitrile was used to introduce acrylamide functionality on the triglyceride. Acrylonitrile and triglycerides were reacted in the presence of H₂SO₄, and acrylamide derivatives were obtained in yields of 45 and 50% for sunflower oil and soybean oil, respectively. Radical initiated copolymerization of the acrylamide derivatives of the triglycerides with styrene produced semirigid polymers. Characterization of new monomers and polymers was done by ¹H‐NMR, ¹³C‐NMR, IR, and MS. The swelling behavior of the crosslinked network polymers was determined in different solvents. Glass transiton temperature (T_g) of the cured resin was also determined by differential scanning calorimeter to be 40°C for soybean based polymer and 30°C for sunflower‐based polymer. Homo‐ and copolymerization behavior of acrylamide derivatives of methyl oleate (MOA) and methyl 10‐undecenoate (MUA) were also investigated. The reactivity ratios of these monomers with respect to styrene were determined by the Fineman–Ross method using ¹H‐NMR spectroscopic data. The reactivity ratios were r_sty = 1.776; r_moa = 0512 for MOA, and r_sty = 1.142; r_mua = 0.507 for MUA, respectively. Photopolymerization behaviors of MOA and MUA were also investigated using the photoDSC technique and the rate of polymerization of MUA is higher than that of MOA under the same conditions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2264–2272, 2005     

Biobased polyisocyanates from plant oil triglycerides: Synthesis,polymerization, and characterization

In this study, an easy and efficient synthesis of unsaturated plant oil triglycerides having isocyanate groups is reported. In the first step of the synthesis, the triglyceride was brominated at the allylic positions by a reaction with N‐bromosuccinimide, and in the second step, these brominated species were reacted with AgNCO to convert them to isocyanate‐containing triglycerides. At the end of the reaction, approximately 60–70% of the bromine was replaced by NCO groups, and the double bonds of the triglyceride were not consumed. When the amount of AgNCO was increased, the yield also increased. The final products were characterized with IR and ¹H‐NMR, and polyurethanes and polyureas were obtained from these fatty isocyanates with alcohols and amines, respectively. The polymers were characterized by differential scanning calorimetry and thermogravimetric analysis. Differential scanning calorimetry curves showed that glycerin polyurethane showed a glass‐transition temperature at 19°C, castor oil polyurethane showed two glass‐transition temperatures at ?43 and 36°C, and triethylene tetraamine polyurea showed a glass‐transition temperature at 31°C. Some properties of the polymers, such as the tensile strength and swelling ratios, were also determined. The swelling rate of glycerin polyurethane was higher than that of castor oil polyurethane in dichloromethane. The equilibrium swelling ratio was highest for the castor oil polyurethane. The polyurethanes synthesized in this study had a Young's modulus around 50 kPa and a tensile strength around 0.01 N/mm² (100 kPa). The tensile strength of glycerin polyurethane was higher than that of castor oil polyurethane. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Thermal analysis of solution copolymers of styrene with N‐phenylmaleimide

Free‐radical–initiated copolymerization of N‐phenylmaleimide (NPMI) with styrene (St) at 110°C in a toluene solution initiated by AIBN was carried out by a semibatch method. The compositions of the copolymers were determined by using an elemental analyzer. The glass‐transition temperatures of the copolymers were measured by differential scanning calorimetry. All the semibatch copolymers show a single glass‐transition temperature that increases markedly with increasing NPMI content in the copolymers. The thermal stabilities of the copolymers were studied by using a programmed thermogravimetric analysis technique. Copolymers show a considerable increase in thermal stability and different degradation reaction mechanisms with increasing content of NPMI. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 417–422, 2002     

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     

Thermal and thermo‐oxidative degradation properties of poly(benzimidazole amide imide) copolymers

In this study, 3,3′‐dinitrobenzidine was first reacted with excess isophthaloyl chloride to form a monomer with dicarboxylic acid end groups. Two types of aromatic dianhydride, [viz., pyromellitic dianhydride (PMDA) and 3,3′,4,4′‐sulfonyldiphthalic anhydride (DSDA)] also were reacted with excess 4,4′‐diphenyl‐ methane diisocyanate (MDI) to form polyimide prepolymers terminated with isocyanate groups. The prepolymers were reacted further with the diacid monomer to form a nitro group–containing aromatic poly(amide imide) copolymers. The nitro groups in these copolymers were hydrogenated to form amine groups and cyclized at 180°C to form the poly(benzimidazole amide imide) copolymers in polyphosphoric acid (PPA), which acts as a cyclization agent. From the viscosity measurements, copolymer appeared to be a reasonably high molecular weight. From the differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) measurements it was shown that the glass transition temperature of copolymers was in the range of ～270–322°C. The 10% weight loss temperatures were in the range of 460 ～ 541°C in nitrogen and ～441–529°C in air, respectively. The activated energy and the integration parameter of degradation temperature of the copolymers were evaluated with the Doyle‐Ozawa method. It indicated that these copolymers have good thermal and thermo‐oxidative stability with the increase in imide content. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2072–2081, 2004     

Rigid thermosetting liquid molding resins from renewable resources. II. Copolymers of soybean oil monoglyceride maleates with neopentyl glycol and bisphenol A maleates

Soybean oil monoglycerides (SOMG), obtained by the glycerolysis of soybean oil, were reacted with maleic anhydride to produce SOMG maleate half esters. The copolymers of the SOMG maleates with styrene produced rigid thermosetting polymers. The dynamic mechanical analysis (DMA) of this polymer showed a glass‐transition temperature (T_g) around 133°C and a storage modulus (E′) value around 0.94 GPa at 35°C. The tensile tests performed on this polymer showed a tensile strength of 29.36 MPa and a tensile modulus of 0.84 GPa. Mixtures of SOMG with neopentyl glycol (NPG) and SOMG with bisphenol A (BPA) were also maleinized under the same reaction conditions and the resulting maleates were then copolymerized with styrene. The resulting polymers were analyzed for their mechanical properties. The T_g of the copolymers of the SOMG/NPG maleates with styrene was 145°C and the E′ value at 35°C was 2 GPa. The tensile strength of this polymer as calculated from the stress–strain data was 15.65 MPa and the tensile modulus was 1.49 GPa. The T_g of the copolymers of SOMG/BPA maleates, on the other hand, was found to be around 131°C and the E′ value was 1.34 GPa at 35°C. The changes observed in the mechanical properties of the resulting polymers with the introduction of NPG maleates and BPA maleates to the SOMG maleates can be explained by the structural changes on the polymer backbone. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 972–980, 2002     

Rigid,thermosetting liquid molding resins from renewable resources. I. Synthesis and polymerization of soy oil monoglyceride maleates

In this study, rigid thermoset polymers were prepared from radical copolymerization of the soybean oil monoglyceride maleates with styrene. In the first part of the study, soybean oil monoglycerides (SOMGs) were obtained from the reaction of soybean oil with glycerol at 220–240°C with an optimization of the reaction to maximize the monoglyceride yield. In the following step, SOMG were reacted with maleic anhydride at temperatures around 100°C to produce the SOMG maleate half esters. Different catalysts and different reaction conditions were examined to increase the maleate half esters' yields. The reactions were followed by IR and ¹H NMR, and the products were characterized by mass spectrometry. In the final step, the radical initiated copolymerization of the SOMG maleates with styrene produced rigid, thermoset polymers. The emulsion copolymerization of the SOMG maleates with styrene was also carried out successfully without the addition of an emulsifier. The obtained polymers were characterized by IR and the crosslinked network structure of the copolymers was examined with the swelling behavior in different solvents. Mechanical properties of the cured resin such as T_g, dynamic flexural modulus, and surface hardness were also determined. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 69–77, 2001     

Synthesis and characterization of novel rod–coil diblock copolymers of poly(methyl methacrylate) and liquid crystalline segments of poly(2,5‐bis[(4‐methoxyphenyl)oxycarbonyl] styrene)

Liquid crystalline diblock copolymers with different molecular weights and low polydispersities were synthesized by atom transfer radical polymerization of methyl methacrylate (MMA) and 2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene (MPCS) monomers. The block architecture (coil‐conformation of MMA segment and rigid‐rod of MPCS segment) of the copolymer was experimentally confirmed by a combination of ¹H nuclear magnetic resonance and gel permeation chromatograph techniques. The liquid crystalline behaviour of the copolymer was studied using differential scanning calorimetry and polarized optical microscope. It was found that the liquid crystalline behaviour was dependent on the number average molecular weight of the rigid segment. Only those copolymers with M_n(GPC) of the rigid block above 9200 g mol^?1 could form liquid crystalline phases higher than the glass transition temperature of the rigid block. The random copolymers MPCS‐co‐MMA were also synthesized by conventional free radical polymerization. The molar content of MPCS in MPCS‐co‐MMA had to be higher than 71% to maintain liquid crystalline behaviour. © 2003 Society of Chemical Industry     

Gelation of soybean oil with polybutadiene

In this study self‐supporting, resilient, load bearing polybutadiene ‐ soybean oil gels were obtained. The gels were made by dissolving polybutadiene (PBD) in soybean oil (SO) and selectively crosslinking PBD with a free radical source. PBD concentration, free radical source concentration, and the temperature and time of the crosslinking reaction were varied, and the effects of these changes on the mechanical properties of the gels were examined. Our experiments show that successful gelation is possible within PBD concentration limits of 7.5 to 12%, peroxide concentration between 25 to 100% (based on PBD), temperature between 110°C and 130°C and reaction times of 3 hours with tert.butyl‐peroxybenzoate as the free radical source. The crosslinking reaction was followed by IR and H‐NMR spectra, and the crosslinking density was followed by compression testing and swelling behavior. Higher radical source concentration and higher PBD concentration gave gels with better mechanical properties. The spectra and the viscosity increase of SO extracted from the gels indicate that there is dimer and trimer formation of SO during the reaction. The spectra of the PBD extracted from gels indicate that SO was added to PBD in a small but measurable amount. Integration of peak intensities in the NMR spectrum of methylene groups of PBD and methylene groups of triglyceride indicated one triglyceride molecule for approximately 45 repeating units in PBD. The modulus of the best gel sample (PBD 10%. peroxide 50%) was 1.96 × 10^?2 MPa. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2240–2246, 2005     

Preparation of the flexible soybean oil-based material via [2 + 2] cycloaddition photo-polymerization

Polymers with high flexibility and high content renewable biomass materials have attracted particular attention. Plant-derived trans-cinnamic acid (CA) was introduced into the structure of epoxidized soybean oil to form trans-cinnamated epoxidized soybean oil (ESOCA). ESOCA with multi-cinnamate groups was cured via [2 + 2] cycloaddition photo-polymerization that with no need of photoinitiator, while acrylated epoxidized soybean oil (ESOAA) was photocured via free radical photopolymerization for comparison. The successful synthesis of ESOCA and ESOAA resin was proved by Fourier transform infrared, proton nuclear magnetic resonance, and gel permeation chromatography results. ESOCA is more environmentally friendly than ESOAA for that trans-CA volatility is much lower than acrylic acid during synthesis process. Notably, UV-cured ESOCA samples had a higher tensile strength at break and a 14.75 times elongation at break of that of UV-cured ESOAA samples, showing that [2 + 2] cycloaddition photo-polymerization is a good strategy to prepare flexible materials. Performances of ESOCA as coating on flexible PET film were also better than those of ESOAA, especially the flexibility, adhesion, and UV shielding performance. This study may open up a new way for design and synthesize flexible high performance polymer from renewable biomass materials.     

Photocrosslinked biobased phase change material for thermal energy storage

A series of novel photocrosslinked biobased shape‐stabilized phase change materials (PCMs) based on octadecanol, eicosanol and docosanol have been prepared by UV technique for the purpose of thermal energy storage applications. Epoxidized soybean oil was reacted with acrylic acid to form acrylated soybean oil (ASO). The structure and composition, cross‐section morphology, thermal stability performances and phase change behaviors of ASO and UV‐cured PCMs were examined by using Attenuated total reflection fourier transform infrared spectroscopy, thermogravimetric analysis system (TGA), scanning electron microscopy, and differential scanning calorimetry. The results indicate that the UV‐cured biobased PCMs possess perfect phase change properties and a suitable working temperature range. The heating process phase change enthalpy is measured between 30 and 68 J/g, and the freezing process phase change enthalpy is found between 18 and 70 J/g. The decomposition of UV‐cured PCMs started at 260 °C and reached a maximum of 430 °C. All the biobased UV‐cured PCMs improved latent heat storage capacity in comparison with the pristine ASO sample. With the obtained results we conclude that, these materials promise a great potential in thermal energy storage applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43757.     

Thermal and mechanical properties of acrylated expoxidized‐soybean oil‐based thermosets

A series of epoxidized‐soybean oil (ESO) with different epoxyl content were synthesized by in situ epoxidation of soybean oil (SBO). The acrylated epoxidized‐soybean oil (AESO) was obtained by the reaction of ring opening of ESO using acrylic acid as ring opener. The acrylated expoxidized‐soybean oil‐based thermosets have been synthesized by bulk radical polymerization of these AESOs and styrene. The thermal properties of the resins were characterized by differential scanning calorimetry (DSC) and thermo‐gravimetric analysis (TG). The results showed that these resins possess high thermal stability. There were two glass transition temperature of each resin due to the triglycerides structure of the resins. The tensile strength and impact strength of the resins were also recorded, and the tensile strength and impact strength increased as the iodine value of ESO decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010