Biobased nanocomposites from clay modified blend of epoxidized soybean oil and cyanate ester resin

Novel bio-based nanocomposites were prepared by blending surface modified natural clay with epoxidized soybean oil (ESO) and cyanate ester resin (CE). A convenient method was employed to modify the attapulgite (ATT) clay by adsorbing the poly(ethylene glycol) diglycidyl ether (PEGDE) onto the clay surface, which was confirmed by the appearance of a new peak of infrared spectroscopy due to hydrogen bonding and chelation. Thermogravimetic analysis (TGA) showed that the amount of PEGDE adsorbed on ATT was influenced by PEGDE concentration in acetone solution. Scanning electron microscope (SEM) and transmission electron microscope (TEM) results showed that nanoscaled ATT dispersed well in the blend of epoxidized soybean oil (ESO) before and after curing. The thermal-physical and mechanical properties were evaluated by dynamic mechanical analysis (DMA), TGA and tensile mechanical test. The nanocomposites showed higher glass transition temperature and modulus, and the tensile strength of the nanocomposites was reinforced as compared to that of ESO/CE blends.     

紫外光固化环氧豆油丙烯酸酯的制备与表征

将环氧大豆油与丙烯酸反应制备出环氧豆油丙烯酸酯预聚物,讨论了反应温度、反应时间、催化剂、阻聚剂的种类与用量对合成反应的影响,并用红外光谱对产物的结构进行了表征。研究结果表明其最佳反应条件是:催化剂三苯基膦,反应温度110℃,反应时间8h。该预聚树脂可用紫外光固化,其固化膜硬度达3H,且具有较好的柔韧性和附着力。     

Preparation and properties of lubricant basestocks from epoxidized soybean oil and 2-ethylhexanol

Synthetic lubricant basestocks were prepared from epoxidized soybean oil (ESO) and 2-ethylhexanol (2-EH) to be used alone or with polyalphaolefin (PAO). Sulfuric acid-catalyzed reaction of ESO with 2-EH involves a ring-opening reaction at the epoxy group followed by transesterification at the ester group. Reaction with other catalysts including p-toluenesulfonic acid, Dowex 50W-8X, boron trifluoride, and sodium methoxide was also examined. Pour points of the products were observed as lows as −21 and −30°C without and with 1% of pour point depressant, respectively. When the hydroxy groups in the products were esterified with an acid anhydride, lower pour points were observed. Pour point depression of the product by adding PAO has been tested. Oxidative stability of the product was examined using pressurized DSC and compared with those of synthetic lubricant basestocks, PAO, and a synthetic ester.     

Polyols from epoxidized soybean oil and alpha hydroxyl acids and their adhesion properties from UV polymerization

Two types of biobased polyols, ESOGA and ESOLA, were synthesized from epoxidized soybean oil (ESO) with glycolic acid (GA) and lactic acid (LA), respectively, using a solvent-free/catalyst-free method. An ESO epoxy conversion rate of over 93% was achieved for both polyols. ESOGA has a weight-/number-average molecular weight (M_w/M_n) of 27,700/3900 g/mol and average hydroxyl functionality (f_OH) of 12.9, and ESOLA has M_w/M_n of 8800/3000 g/mol and f_OH of 11.7. The structures of the polyols were further characterized with Fourier transform infrared spectroscopy and ¹H-nuclear magnetic resonance. Rheology and thermal properties were studied with a rheometer and a differential scanning calorimeter. The polyols were polymerized with ESO to adhesive polymers using UV light in the presence of cationic photoinitiator. The curing rate decreased as the amount of polyol increased for resins based on ESOGA and ESOLA (EGA and ELA). With the same amount of polyol, ELA resins cured faster than EGA resins. The peel strength and tack of EGA and ELA adhesives increased significantly as the ratio of polyol in the resin increased. ELA exhibited obviously higher peel strength and tack than EGA with the same amount of polyol. All resin tapes exhibited high static shear values (20,000+min). Overall, both ESOGA and ESOLA exhibited great potential as polyols for pressure-sensitive adhesive applications.     

Effect of ultrasonic extrusion on properties of colloids and bio-based nanocomposites containing epoxidized soybean oil and nanoclay

Colloid prepared with epoxidized soybean oil (ESO) and a nanoclay, organically modified montmorillonite (OMMT), has been processed using an ultrasonic twin-screw extruder under various ultrasonic amplitudes and screw rotation speeds. Ultrasonic treatment has significantly increased OMMT dispersion in ESO, according to wide angle X-ray diffraction and rheological data. Yield stress, storage and loss modulus, and complex viscosity and relaxation time of the colloid have been increased with increase of ultrasonic amplitude. Under certain high ultrasonic amplitudes, the increase of one to two orders of magnitude in the above-mentioned properties of colloids has been observed. Creep and recoverable compliance have been decreased with the increase of ultrasonic amplitude. The tremendous changes in rheological properties of the colloid are a result of significantly improved OMMT dispersion with the aid of ultrasonic treatment. With no or low ultrasonic treatment, a higher screw rotation speed has improved OMMT dispersion since it brings more mixing effect. However, at high ultrasonic amplitudes, a higher rotation disrupts jet flow and has led to less dispersion improvement compared with the same colloid extruded at a lower rotation speed. Colloids extruded at 400 rpm were cured using triethylenetetramine to prepare bio-based nanocomposites. The nanocomposite prepared using colloid treated at 13 μm shows improved tensile strength and modulus compared with the nanocomposite prepared using untreated colloid.     

Ion chromatographic determination of phosphorus and tungsten in epoxidized soybean oil

Soybean oil has been epoxidized with hydrogen peroxide in the presence of catalytic amounts of trioctylmethyl-ammonium tetra(diperoxotungsto)phosphate. A fast ion-exchange chromatographic method with suppressed conductivity detection has been developed for determining residual contents of tungsten and phosphorus in the oil. Tungsten and phosphorus could be determined at concentrations of 66 and 11 ppm, respectively. At tungsten and phosphorus concentrations of 1000 and 50 ppm, measured repeatabilities were 1.3 and 1.5%, respectively.     

Modification of epoxidized soybean oil for lubricant formulations with improved oxidative stability and low pour point

To produce soybean oil-based lubricants with good oxidative stability and low pour point, epoxidized soybean oil (SBO) was chemically modified. Epoxidized SBO was reacted with various alcohols in the presence of sulfuric acid as a catalyst to give a ring-opened intermediate product. In this step, the epoxy group was transformed to the functional group of-CH(OR¹)CH(OH)-(where the R¹=methyl, 1-butyl, 2-butyl, 1-hexyl, cyclohexyl, 2,2-dimethyl-1-propyl, or 1-decyl). The ¹H nuclear magnetic resonance spectra of the products indicated that transesterification was accompanied by the ringopening reaction except when the bulky 2,2-dimethyl-1-propanol was used. Acid anhydride was used to esterify the hydroxy groups in the ring-opened product. This resulted in a fluid that is a lubricant candidate with the functional group of −CH(OR¹)CH(OCOR²)−. Pour point studies of the resulting products showed that the pour points varied with the substituents, R¹ and R². Products with R¹=CH₃(CH₂)₅₋ and R²=CH₃(CH₂)₂₋, (CH₃)₂CH−, or CH₃(CH₂)₄-showed the lowest pour points (−39, −39, and −45°C, respectively) when 1% of pour point depressant was added. For the oxidative stability test, two products, in which R¹, R²=CH₃(CH₂)₅₋, (CH₃)₂CH− and R¹, R²=CH₃(CH₂)₅₋, CH₃(CH₂)₄₋, were chosen for a modified Penn State micro-oxidation test. In the oxidative stability test, the products gave 69–71% of oxidative evaporation and 10–17% of tetrahydrofuran-insoluble deposits in 3 h at 175°C. The amounts of deposits were much lower than those of soybean oil (96%) and epoxidized SBO (83%) and even less than those of most petroleum-based lubricant basestocks (3–93%).     

Green approach for the preparation of biodegradable lubricant base stock from epoxidized vegetable oil

A novel process for the production of biodegradable lubricant-based stocks from epoxidized vegetable oil with a lower pour point via cationic ion-exchange resins as catalysts was developed. This involves two steps, first, ring-opening reactions by alcoholysis followed by esterification of the resultant hydroxy group in the first step.

The ring-opening reaction of epoxidized soybean oil with different alcohols such as n-butanol, iso-amyl alcohol and 2-ethylhexanol was carried out in presence of Amberlyst 15 (Dry) as a catalyst; identity of products was confirmed by IR and NMR. Pour points of the products were observed in the range of −5 to −15 °C. The hydroxy group of ring-opening product of n-butanol was further reacted with acetic anhydride in presence of catalyst Amberlyst 15 (Dry), which was previously used to carry out ring-opening reaction by alcoholysis and identity of the resulting product was confirmed by IR. Pour point of the resulting product was observed to be −5 °C.     

Synthesis and characterization of cast resin based on different saturation epoxidized soybean oil

Acrylated epoxidized soybean oils (AESOs) with different level of saturation were obtained by the ring opening of different saturation epoxidized soybean oils using acrylic acid as the ring opener. AESO‐based thermosets have been synthesized by free radical polymerization of these AESOs and methyl methacrylate. The thermal properties of these resins were studied by differential scanning calorimetry and thermo‐gravimetric analysis. The results indicated that the thermal stability of these resins depends upon the epoxy value; the glass transition temperature increases with increasing of epoxy value. The tensile and impact strength of the resins were also studied, and indicated that tensile strength increases with increasing epoxy value, whereas impact strength decreases. The resulting thermosets ranged from elastomers to glassy polymers.     

Polylactic acid/epoxidized palm oil/fatty nitrogen compounds modified clay nanocomposites: Preparation and characterization

Clay modification was carried out by treatment of fatty nitrogen compounds (FNCs); fatty hydrazide (FH), hydroxy methyl fattyamide (HMFA), and difatty acyl thiourea (DFAT) were synthesized from vegetable oils with a sodium montmorillonite (MMT) as natural clay. This process was accomplished by stirring the clay particles in an aqueous solution of FH, HMFA, and DFAT, by which the clay layer thickness increased from 1.23 to 2.69, 2.89 and 3.21 nm, respectively. The modified clay was then used in the preparation of the polylactic acid/epoxidized palm oil (PLA/ EPO) blend nanocomposites. The interaction of the modifier in the clay layer was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR). Elemental analysis was used to estimate the presence of FNCs in the clay. The nanocomposites were synthesized by solution casting of the modified clay and a PLA/EPO blend at the weight ratio of 80/20, which has the highest elongation at break. The nanocomposites were then characterized using XRD, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and tensile properties measurements. Improvement in mechanical properties of the FH-MMT, HMFA-MMT, and DFAT-MMT nanocomposites was obtained when 2% of the DFAT-MMT and 3% of both FH-MMT and HMFA-MMT loadings were used. PLA/EPO modified clay nanocomposites show higher thermal stability in comparison with those of the PLA/EPO blend. The XRD and TEM results confirmed the production of nanocomposites.     

涂料用环氧大豆油的研究进展

介绍了环氧大豆油在阳离子光固化体系、环氧豆油丙烯酸酯涂料及其他涂料体系的研究状况,并对其应用前景进行了展望。     

Synthesis of bio‐based polymeric nanocomposites from acrylated epoxidized soybean oil and montmorillonite clay in the presence of a bio‐based intercalant

Polymeric nanocomposites were synthesized from functionalized soybean‐oil‐based polymer matrix and montmorillonite (MMT) clay using an in situ free radical polymerization reaction. Acrylated epoxidized soybean oil combined with styrene was used as the monomer. Organophilic MMT (OrgMMT) was obtained using a quaternized derivative of methyl oleate, which was synthesized from olive oil triglyceride, as a renewable intercalant. The resultant nanocomposites were characterized using X‐ray diffraction and atomic force microscopy. The effect of increased nanofiller loading on the thermal and mechanical properties of the nanocomposites was investigated using thermogravimetric analysis and dynamic mechanical analysis. It was found that the desired exfoliated nanocomposite structure was achieved when the OrgMMT loading was 1 and 2 wt%, whereas a partially exfoliated or intercalated nanocomposite was obtained for 3 wt% loading. All the nanocomposites were found to have improved thermal and mechanical properties as compared with virgin acrylated epoxidized soybean‐oil‐based polymer matrix. The nanocomposite containing 2 wt% OrgMMT clay was found to have the highest thermal stability and best dynamic mechanical performance. Copyright © 2010 Society of Chemical Industry     

Microstructure and rheological behavior of block copolymer/clay nanocomposites

Organic/Inorganic hybrid nanocomposites based on poly(styrene-butadiene-styrene) copolymer (SBS) and clay are fabricated by melt intercalation. The degree of intercalation is dependent on the surface properties of clay and SBS. The epoxized block in epoxized SBS acts as a strong attractive site with the clay surface, which yields the increased interlayer space in the layered silicates. It is also shown that the thermal stability of clay as well as the surface properties is very important in fabricating the polymer/clay nanocomposites. The rheological behavior of the SBS/clay nanocomposites is quite different from that of SBS itself. Both storage moduli and complex viscosity of the SBS/layered silicate nanocomposites increase and show non-terminal flow behavior.     

Preparation and properties of zeroTrans soybean oil margarines

Experimental margarines were prepared in the pilot plant from interesterified soybean oil-soybean trisaturate blends and compared to a product made from hydrogenated soybean oil. Penetration, yield values, and water/oil off-data were determined. Margarine prepared from an interesterified soy-soy trisaturate blend (80:20) tended to crystallize slowly after votation and resulted in a somewhat harder than desirable product. However, addition of 20% liquid soybean oil to the interesterified oil yielded a softer product. The experimental products showed excellent oil and water loss properties under accelerated storage conditions.     

Mechanical and rheological properties of epoxidized soybean oil plasticized poly(lactic acid)

Poly(lactic acid) (PLA) is a well known biodegradable thermoplastic with excellent mechanical properties that is a product from renewable resources. However, the brittleness of PLA limits its general applications. Using epoxidized soybean oil (ESO) as a novel plasticizer of poly(lactic acid), the composite blend with the twin‐screw plastic extruder at five concentrations, 3, 6, 9, 12, and 15 wt %, respectively. Compared with pure PLA, all sets of blends show certain improvement of toughness to different extents. The concentration with 9 wt % ESO increases the elongation at break about 63%. The melt flow rates of these blends with respect to different ESO ratio have been examined using a melt flow indexer. Rheological behaviors about shear viscosity and melt strength analysis are discussed based on capillary rheology measurements. The tensile strength and melt strength of the blends with 6 wt % ESO simultaneity reach the maximums; whereas the elongation at break of the blends is the second highest level. ESO exhibits positive effect on both the elongation at break and melt strength. The results indicate that the blend obtained better rheological performance and melt strength. The content of 6 wt % ESO in PLA has been considered as a better balance of performance. The results have also demonstrated that there is a certain correlation between the performance in mechanical properties and melt rheological characterization for the PLA/ESO blends.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Preparation and crystalline morphology of biodegradable starch/clay nanocomposites

An organically modified clay (o-clay) and a pristine clay (p-clay) were used to prepare biodegradable thermoplastic starch (TPS)/clay nanocomposites by melt processing. The gelatinization behaviour of starch with glycerol/H₂O was investigated and the gelatinized temperature (T_gel) was determined using a polarized optical microscopy (POM) equipped with a hot stage. The morphologies of gelatinized starch and extruded starch were revealed by scanning electron microscopy (SEM). Thermal stabilities of starch/clay nanocomposites were evaluated under N₂ atmosphere using thermogravimetric analysis (TGA). Transparent films of starch/clay hybrids were fabricated by hot pressing. Intercalation of starch into clay galleries and crystalline structure of starch were investigated using X-ray diffraction (XRD). It was found that the increase in d-spacing of organically modified clay was due to starch molecular intercalation while the increase in d-spacing of pristine clay was mostly caused by glycerol intercalation because of the narrow valid d-spacing of pristine clay and special ring-like monomer of starch. The mechanism of starch intercalation in clay galleries was discussed.     

无硫酸环境环氧化大豆油合成条件优化

在无溶剂无硫酸条件下合成了环氧大豆油,对环氧化合成体系中的羧酸类型、用量及双氧水浓度等影响环氧值的若干因素进行了研究。甲酸的环氧化活性比乙酸和丙烯酸高。通过正交实验确定了最佳合成工艺条件为:m(大豆油)m(甲酸)m(双氧水)为1 0.15 1.0,反应温度60℃,反应时间5～6 h。产品环氧值≥6.20%,残留碘值<6.0%。产品经红外分析表明,在3008 cm-1处的原料C=C双键结构峰消失,在820 cm-1、787 cm-1处呈现出环氧键的伸缩振动的特征吸收峰。     

Hybrid networks based on epoxidized camelina oil

Lately, renewable resources received great attention in the macromolecular compounds area, regarding the design of the monomers and polymers with different applications. In this study the capacity of several modified vegetable oil-based monomers to build competitive hybrid networks was investigate, taking into account thermal and mechanical behavior of the designed materials. In order to synthesize such competitive nanocomposites, the selected renewable raw material, camelina oil, was employed due to the non-toxicity and biodegradability behavior. General properties of epoxidized camelina oil-based materials were improved by loading of different types of organic-inorganic hybrid compounds – polyhedral oligomeric silsesquioxane (POSS) bearing one (POSS1Ep) or eight (POSS8Ep) epoxy rings on the cages. In order to identify the chemical changes occurring after the thermal curing reactions, FT-IR spectrometry was employed. The new synthesized nanocomposites based on epoxidized camelina oil (ECO) were characterized by dynamic mechanical analyze and thermogravimetric analyze. The morphology of the ECO-based materials was investigate by scanning electron microscopy and supplementary information regarding the presence of the POSS compounds were establish by energy dispersive X-ray analysis and X-ray photoelectron spectroscopy. The smooth materials without any separation phase indicates a well dispersion of the Si–O–Si cages within the organic matrix and the incorporation of this hybrid compounds into the ECO network demonstrates to be a well strategy to improve the thermal and mechanical properties, simultaneously.     

Polyurethane/clay nanocomposites foams: processing, structure and properties

Polyurethane (PU)/montmorillonite (MMT) nanocomposites were synthesized with organically modified layered silicates (organoclays) by in situ polymerization and foams were prepared by a batch process. Clay dispersion of polyurethane nanocomposites was investigated by X-ray diffraction and transmission electron microscopy. The morphology and properties of PU nanocomposites and foams greatly depend on the functional groups of the organic modifiers, synthesis procedure, and molecular weight of polyols because of the chemical reactions and physical interactions involved. Silicate layers of organoclay can be exfoliated in the PU matrix by adding hydroxyl and organotin functional groups on the clay surface. The presence of clay results in an increase in cell density and a reduction of cell size compared to pure PU foam. In the polyurethane with high molecular weight polyol, a 6 °C increase in T_g, 650% increase in reduced compressive strength, and 780% increase in reduced modulus were observed with the addition of 5% organically treated clays. Opposite effects were observed in PU nanocomposite foams with highly crosslinked structure. The interference of the H-bond in the presence of clay is probably the reason.     

Water-blown rigid and flexible polyurethane foams containing epoxidized soybean oil triglycerides

Both rigid and flexible water-blown polyurethane foams were made by replacing 0–50% of Voranol® 490 for rigid foams and Voranol® 4701 for flexible foams in the B-side of foam formulation by epoxidized soybean oil. For rigid water-blown polyurethane foams, density, compressive strength, and thermal conductivity were measured. Although there were no significant changes in density, compressive strength decreased and thermal conductivity decreased first and then increased with increasing epoxidized soybean oil. For flexible water-blown polyurethane foams, density, 50% compression force deflection, 50% constant force deflection, and resilience of foams were measured. Density decreased first and then increased, no changes in 50% compression force deflection first and then increased, increasing 50% constant force deflection, and decreasing resilience with increase in epoxidized soybean oil. It appears that up to 20% of Voranol® 490 could be replaced by epoxidized soybean oil in rigid polyurethane foams. When replacing up to 20% of Voranol® 4701 by epoxidized soybean oil in flexible polyurethane foams, density and 50% compression deflection properties were similar or better than control, but resilience and 50% constant deflection compression properties were inferior. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008