Soy Polyol Research Articles

Microencapsulation of Phase Change Materials with a Soy Oil-Based Polyurethane Shell via Pickering Emulsion Polymerization

Phase change materials (PCMs) have been widely investigated for their ability to store enormous amounts of heat while maintaining ambient temperature during phase transition. In this study, microencapsulation PCMs (MEPCMs) were synthesized using the Pickering emulsion method to address PCMs’ defects, such as severe leakage during phase transition. In this paper, modified SiO2 nanoparticles are used as emulsion stabilizers, and a polyurethane (PU) shell prepared from biobased soy polyols is used to encapsulate PCM ethyl palmitate for the successful fabrication of microcapsules. According to the findings, when the dosage of modified SiO2 nanoparticles reached 0.5 wt %, the morphologies and mechanical performance of microcapsules reached their optimal condition. Meanwhile, M-SiO2-doped microcapsules have greater thermal stability than pure ethyl palmitate. Differential scanning calorimetry (DSC) analysis indicates that when the core–shell ratio grows, the MEPCMs’ heat storage capacity increases. The latent heat of MEPCMs reached 118.5 J/g as the core–shell ratio reached 2:1. Additionally, a higher core–shell ratio could help alleviate the supercooling phenomenon of microencapsulation PCMs (MEPCMs). Moreover, the MEPCMs’ energy storage efficiency can reach 93.3% after 50 cycles of heat and cold, demonstrating that they have excellent cycle stability.

Bio-polyols based waterborne polyurethane coatings reinforced with chitosan-modified ZnO nanoparticles

The development of environmentally friendly waterborne polyurethane (WPU) coatings from bio-based polyols has received much attention due to increasing environmental concern and the depletion of petroleum resources. In this study, the WPU coatings derived from castor oil and soy polyol were modified by chain extender [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester. The effect of chitosan-modified ZnO (CS-ZnO) nanoparticles content on the properties of WPU/CS-ZnO coatings and their films were systematically investigated. The results indicated that WPU/CS-ZnO coatings displayed excellent storage stability and the particle sizes firstly decreased and then increased with CS-ZnO loading. CS-ZnO could improve tensile strength and Young's modulus but reduce the optical transparency of WPU/CS-ZnO films. CS-ZnO has a prominent reinforcement effect on the WPU/CS-ZnO matrix. With the addition of 2 wt% CS-ZnO, the tensile strength and Young's modulus of the WPU/CS-ZnO2 film reached 13.4 and 112.1 MPa, 1.68 and 2.6 times over neat WPU film, respectively. TGA results showed that the thermal stability of WPU/CS-ZnO films improved with increased CS-ZnO content. Furthermore, the WPU/CS-ZnO films' wettability decreased with the introduction of CS-ZnO. This work provides a simple and efficient strategy for preparing environmentally friendly bio-based WPU coatings, which are promising for application in the surface coating industry.

Flame Retardant Modified Bio‐Based Waterborne Polyurethane Dispersions Derived from Castor Oil and Soy Polyol

AbstractAlthough tremendous efforts have been dedicated to developing environmentally friendly bio‐based waterborne polyurethane (WPU) dispersions from vegetable oil, the fabrication of WPU dispersions solely derived from vegetable oil‐based polyol with excellent comprehensive properties is still challenging. In the present work, novel bio‐based WPU dispersions derived from castor oil and soy polyol is successfully modified by phosphorus‐nitrogen chain extender [bis(2‐hydroxyethyl)amino]‐methyl‐phosphonic acid dimethyl ester (BH). The structure and properties of the dispersions and films are characterized systematically by Fourier transform infrared spectroscopy, thermogravimetric analysis , mechanical test, and limiting oxygen index (LOI), etc. The results indicate that bio‐based WPU films display moderate mechanical performance by adjusting BH content, and the WPU film containing 100% BH with 47.8% biobased content has a tensile strength of 8 MPa and the highest Young's modulus of 62.3 MPa. The incorporation of BH can increase the production of char residue. The flame retardancy of WPU films increase gradually with the BH molar content, and the LOI value of the WPU100 with 1.53 wt% phosphorus content can reach as high as 28.1%. This work may provide a new approach to develop high biobased content, eco‐friendly, flame retardant WPU for application in the surface coating industry.

The Synergize effect of Chain extender to Phosporic acid catalyst to the ultimate property of Soy-Polyurethane

The polyurethanes (PUs) foam were made from vegetable oil; a soybean based polyol. The foams were categorized into flexible and semi rigid. This research is manufacturally designed polyurethane foams by a process requiring the reaction of mixture of 2, 4- and 2, 6-Toluene di Isocyanate isomers, soy polyol in the presence of other ingredients. The objective of this work was to functionalized soy-polyol using phosporic acid catalyst and chain extender, study their collaborative reaction in producing ultimate property of PU foam. Correlates the foam morphology images in accordance to mechanical properties of foams.

One-pot synthesis and physicochemical properties of high functionality soy polyols and their polyurethane-Urea coatings

This paper explores a new approach for the synthesis of highly functional soy polyol (SP) from soybean oil (SBO). A two-step continuous route has been reported for the development of renewable polyols and their polyurethane/urea (PU-Urea) coatings. The methodology includes epoxidation of oils and subsequent hydroxylation to produce polyols. The SBO and SP were characterized by different spectroscopic techniques such as 1H and 13C nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy, Gel permeation chromatography (GPC), Differential scanning calorimetry (DSC) and Thermogravimetric analysis (TGA), and rheological properties were also determined. Through the present approach, we were able to achieve hydroxyl number for SP as high as 231.3mg KOH/g. Additionally, the relative conversion of epoxide value as 0.001% and iodine value under 1.35 (g of I2 100/g) are superior to the past reports. Different PU-Urea coatings obtained by utilization of the high functionality SP, exhibited excellent thermo-mechanical and solvent resistances. It was found that the molecular design of polyisocyanate and functionality of polyol plays an important role on performance properties of the coatings. The coatings were also evaluated for their in-vitro degradation, contact angle and chemical resistance properties. We observed high glass transition (Tg 171.8°C), superior cross-linking density of the PU network, chemical resistance and lower degradation rates. The present work can provide an insight on the design and development of high functionality bio-polyols and their PU-Urea coatings.

Systematic study on substituting petroleum-based polyols with soy-based polyol for developing renewable hybrid biofoam by self-catalyzing/rising process

The future depletion of petroleum resources is driving development of sustainable alternatives based on biomass materials. This work is aimed at developing rigid polyurethane biofoam with similar properties to commercial foam for the potential application in thermal insulation. we designed a hybrid biofoam by self-catalyzing/rising process from substituting petroleum polyol with soy polyol.

Effects of soy-based oils on the tensile behavior of EPDM rubber

The effects of soy-based oil on the constitutive behavior of EPDM rubber have been investigated. Soy polyols with various hydroxyl numbers as well as unmodified soybean oil have each been incorporated in the EPDM rubber as a partial replacement for petroleum oil. Tensile tests have been performed at low and high rates, and hysteresis and stress relaxation tests have been performed at low rates. It has been found from the tensile tests that the rubber with soy polyol of low hydroxyl number can provide very similar constitutive characteristics as the control. On the other hand, the constitutive characteristics are significantly changed by using soy polyol of high hydroxyl number or unmodified soybean oil. For example, the rubber with unmodified soybean oil elongates substantially up to stretch ratios of 13, which is approximately 100% greater than that of the control. It has also been found from the tensile and hysteresis tests that the soy-based rubbers generally have better energy storing and dissipation characteristics than the control, such as storing more energy while maintaining lower peak stress, for an impact application. The test results indicate the potential for application based tuning of soy rubber properties by selecting an appropriate soy oil/EPDM blend or a polyol/EPDM blend with optimized functionality.

Carbon nanofibers reinforced soy polyol-based polyurethane nanocomposites

Vapor-grown carbon nanofiber (CNF)-modified soy polyol-based polyurethane (PU) nanocomposites with different hydroxyl value of polyols (OH) were synthesized. The glass transition, thermal stability, mechanical properties, and morphology of the PU nanocomposites were characterized through differential scanning calorimetry, thermogravimetry, universal test machine, and scanning electron microscopy. The addition of CNFs increased the glass transition temperature as well as significantly improved tensile strength and Young’s modulus of PU nanocomposites. Meanwhile, thermal and mechanical properties of PU composites were influenced by the different hydroxyl value of polyols due to those different structures. In particular, in the case of 2 mass% CNF addition in PU derived from soy polyol with the OH number of 164 mg KOH g−1, 20.8 °C improvement in the glass transition temperature, 115 % increment in tensile strength, and nearly eightfold increase in Young’s modulus were obtained.

Polyurethane molded foams with high content of hyperbranched polyols from soybean oil

This paper examines the feasibility of using polyols from vegetable oils as base polyols (i.e. with 50% or more in a blend with petrochemical polyols) for flexible molded polyurethane foams. A series of hyperbranched (HB) polyols were synthesized by transesterification of hydroxy fatty acid methyl esters and different modifiers to control viscosity, hydrophilicity, molecular weight, and functionality. All HB polyols had hydroxyl numbers around 85 mg KOH/g, with the exception of one which was 105 mg KOH/g. When mixed with petrochemical polyols with OH numbers 35 and 28 mg KOH/g, the HB polyols acted primarily as high molecular weight crosslinkers that increased the stiffness of the polymeric network and the load-bearing properties but decreased the tensile strength, elongation, and tear strength. However, most of the foams met the targeted tensile and tear strength values while some of the foam formulations provided satisfactory elongation. The best mechanical properties were obtained from foams with phthalic anhydride-modified HB polyols. It was demonstrated that flexible molded foams with satisfactory properties can be obtained with 50% and 65% of HB soy polyols in a blend with PPO polyols.

Thermo‐Mechanical and Antibacterial Properties of Soybean Oil‐Based Cationic Polyurethane Coatings: Effects of Amine Ratio and Degree of Crosslinking

AbstractSoybean‐oil‐based cationic polyurethane coatings with antibacterial properties have been prepared with a range of different molar ratios of hydroxyl groups from an amine diol. A second series of polyurethane coatings were prepared from soy polyols with different hydroxyl numbers. All of the cationic PU dispersions and films exhibit inhibitory activity against three foodborne pathogens: Salmonella enterica ssp. enterica ser. Typhimurium, Listeria monocytogenes, and Staphylococcus aureus. It is generally observed that increases in the ratio of ammonium cations improve the antibacterial performance. Reduction of the crosslink density by decreasing the hydroxyl number of the soy polyol also results in slightly improved antibacterial properties. Higher glass transition temperatures and improved mechanical properties are observed with corresponding increases in the molar ratios of the amine diol and the diisocyanate. These results show that the mechanical properties of these coatings can be tuned, while maintaining good antibacterial activity.

Development of Lignin and Nanocellulose Enhanced Bio PU Foams for Automotive Parts

The green rigid polyurethane (PU) foam has been developed with 100 % soy polyol after optimization of formulation ingredients and lignin has been introduced and isocyanate content reduced in the green rigid PU foam. The cellulosic nanofibers have also been successfully incorporated and dispersed in green rigid PU foam to improve the rigidity. The influence of nano cellulose fiber modification (enzymatic treatment, hydrophobic modification with latex) on the foam density, open cell content, foam raise height, water vapor, and mechanical properties of rigid PU foam were studied. The foamed structures were examined using scanning electron microscopy to determine the cell size and shape due to the addition of cellulosic nanofibers. The odor test were performed to evaluate the odor concentration 100 % soyol based PU foam including lignin and nanofiber and compared to 100 % synthetic based polyol PU foam. The experimental results indicated that the compression and impact properties improved due to the modification of nano cellulosic fibers. The odor concentration level of nanofiber reinforced rigid PU foam reduced significantly compared to 100 % PU foam due to the replacing of isocyanate content. It can be said that with an appropriate combination of replacing isocyanate by lignin and addition of nanofiber, rigid PU foam properties could be improved.

Ring opening of epoxidized methyl oleate using a novel acid-functionalized iron nanoparticle catalyst

Hydroxyl soybean oils, also called soy polyols, are biobased chemicals designed to replace petroleum-based polyols mainly for polyurethane (PU) applications. Soy polyols are obtained by acid-catalyzed ring opening of expoxidized soybean oils or other epoxidized plant oils by nucleophilic SN2 attack of methanol. Recyclable heterogeneous catalysts are preferred for the ring-opening reactions over non-recyclable homogeneous catalysts because they minimize environmental impact. The drawbacks of current solid catalysts such as SAC 13 and Amberlite 15 are low production yield and high energy consumption. Here, we demonstrate a greener synthetic pathway of soy polyols with low energy consumption and excellent atom economy and environment (E) factor by using novel sulfamic acid-functionalized iron (iron/iron oxide core shell) nanoparticles (NPs) as a heterogeneous catalyst. The excellent selectivity of the reaction with the recyclable NPs was confirmed by 1H NMR, 1H-1H COSY NMR, and ESI-MS comparable to non-recyclable H2SO4. The synthetic route with the NPs resulted in higher product yield (almost 100%) as H2SO4 at room temperature for 30 min over the SAC 13 (83% yield at 60 °C for 60 min) and Amberlite 15 (87% yield at 60 °C for 100 min). Life cycle assessment (LCA) revealed that the NP synthetic technology for soy polyol production is superior or equal to the competing routes (H2SO4, SAC 13, and Amberlite 15 methods) with respect to 9 environmental impacts (acidification potential, ozone depletion potential, smog formation potential, global warming potential, human toxicity by ingestion, human toxicity by inhalation, persistence, bioaccumulation, and abiotic resource depletion potential).

Synthesis and characterization of novel polyurethane acrylates based on soy polyols

AbstractNovel polyurethane acrylates (PUAs) were prepared by the reaction of soy polyols with isophorone diisocyanate and hydroxyethylacrylate. FTIR results confirmed the formation of PUAs from different kinds of soy polyols. The glass transition, damping properties, thermal stabilities, and mechanical properties of PUAs were characterized by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and universal test machine. The morphology of PUAs was investigated by scanning electron microscope (SEM). The results of the swelling experiments showed that the crosslinking density of polyurethanes and PUAs directly correlated with the hydroxyl (OH) number of polyols. The DSC and DMA results displayed that the glass transition temperature of PUAs was higher than that of polyurethanes and increased with OH number. Furthermore, the formation of PUA networks improved the damping properties of polyurethanes. TGA results demonstrated the acrylation of polyurethanes improved its thermal stability. The initial decomposition temperature of polyurethanes and PUAs also increased with OH number. When compared with polyurethanes, the tensile strengths of PUAs were improved by 118%, 39%, and 9%, respectively, with the increase of OH number of three soy polyols. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.

Rigid polyurethane foam based on modified vegetable oil

AbstractSoybean oil and castor oil were modified and used to prepare rigid polyurethane foam with similar properties to a commercial foam used for thermal insulation applications. Soybean oil was firstly modified according to a peracid method, using formic acid and hydrogen peroxide to yield a formiated soy polyol. Furthermore, transesterification was performed with a polyfunctional alcohol to increase OH‐functionality. Castor oil, which has hydroxyl groups in the molecular structure, was only transesterified. The vegetable polyols were characterized by OH‐number, Brookfield viscosity, differential scanning calorimetry, and size exclusion chromatography. The foams were prepared at constant NCO/OH ratio (1.2 : 1) by the hand mix method and poured into a closed steel box. They were characterized using scanning electron microscopy, thermogravimetric analysis, and dynamic mechanical analysis. The apparent density and the compression strength of foams were determined, respectively, by the mass/volume relation and through the table tensile tester. After modification, the polyols reached an OH‐number between 393 and 477 mg KOH/g oil, showing a low viscosity and molecular weight, allowing the preparation of a rigid vegetable foam with an apparent density of 50 ± 1 kg/m3 and compression strength around 200 kPa. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Effect of vegetable‐based polyols in unimodal glass‐transition polyurethane slabstock viscoelastic foams and some guidance for the control of their structure–property behavior. I

AbstractWe investigated the synthesis and structure–property behaviors of two types of vegetable‐oil polyols (soy oil and castor oil) and their use in viscoelastic (VE) polyurethane foams (PUFs). This article is the first in a two‐part series. In this initial part, we principally address the dynamic mechanical analysis (DMA) behavior of these foams in conjunction with information on the cellular morphology, sol fraction, and rise and reaction temperature profile behavior (the latter two parameters were determined during the foaming process). Particular emphasis is placed on the DMA damping characteristics, which represent one of the most critical parameters in the application of VE PUFs. It is also shown that the damping characteristics could be modified in such foams by the variation of the isocyanate/hydroxyl (×100) index, the addition of plasticizer, and in the case of soy polyols, the soy content. The frequency dependence of the VE PUFs is also briefly addressed. In the second article in this series, which directly follows this article, we further address the details of other relevant physical properties of these same foams in view of their applied nature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Effect of vegetable-based polyols in unimodal glass-transition polyurethane slabstock viscoelastic foams and some guidance for the control of their structure-property behavior. II

We investigated the synthesis and structure–property behaviors of two types of vegetable-oil polyols (soy oil and castor oil) and their use in viscoelastic (VE) polyurethane foams (PUFs). This article is the first in a two-part series. In this initial part, we principally address the dynamic mechanical analysis (DMA) behavior of these foams in conjunction with information on the cellular morphology, sol fraction, and rise and reaction temperature profile behavior (the latter two parameters were determined during the foaming process). Particular emphasis is placed on the DMA damping characteristics, which represent one of the most critical parameters in the application of VE PUFs. It is also shown that the damping characteristics could be modified in such foams by the variation of the isocyanate/hydroxyl (×100) index, the addition of plasticizer, and in the case of soy polyols, the soy content. The frequency dependence of the VE PUFs is also briefly addressed. In the second article in this series, which directly follows this article, we further address the details of other relevant physical properties of these same foams in view of their applied nature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Nanoclay Modified Water-Blown Polyurethane Foams Derived from Bifunctional Soybean Oil-Based Polyol

In this brief communication, we report on the modification of polyurethane (PU) foams based on bifunctional soy bean oil-based polyol by nanoclay. Presence of clay at small loading has been observed to make the foam system more rigid. Modification has been analyzed by measurements on density and compressive strength. In addition, differential scanning calorimetry and thermogravimetric analysis have been used to explain changes in properties of the foams. Scanning electron microscopy have been used to verify the foam rigidity in presence of nanoclay. We conclude that nanoclays are capable of strengthening PU foams derived from bifunctional soy polyol.

Synthesis of Soy-Polyol by Two Step Continuous Route and Development of Soy-Based Polyurethane Foam

Soy-polyol has been synthesized via a low energy two-step continuous route thus avoiding intermediate steps and chemicals. The functional groups of soy-polyol thus produced were identified by Fourier transform infrared (FTIR) spectroscopy which confirmed the cleavage of the double bonds, the formation of new epoxy linkages and the presence of hydroxyl groups. The change in chemical structure and physical properties of the soy polyol was further characterized and the results indicated a successful conversion with reduced unsaturation, increased hydroxyl number and increased viscosity. Polyurethane foam was prepared from soy-polyol using isocyanate and thermogravimetric analysis was used to study its thermal decomposition behaviour. Multiple transitions were identified in relation to depolymerization and bond dissociation. Density and compressive strength of the soy-foam were found to be satisfactory. An investigation of microstructure of soy foam by scanning electron microscope and X-ray computed tomography revealed the internal cell morphology and cell structure.

Water‐blown soy polyol based polyurethane foams modified by cellulosic materials obtained from different sources

AbstractThis article deals with the effect of cellulosic fiber from commercially available writing paper, bleached kraft pulp, and commercially available rice flour on the foaming of polyurethane based on polyol derived from soy bean oil. The presence of cellulosic materials was observed to have a notable influence on the density of the foams. Changes in the density of different foams were correlated with possible chemical structures generated in the presence of the fiber and were analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis. Furthermore, differential scanning calorimetry analysis was performed to lend support to possible changes in foaming behavior in the presence of refined fiber. Scanning electron microscopy observations were in line with the observation of structures generated in the presence of cellulosic fibers from different sources. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Thermal and mechanical properties of cast polyurethane resin based on soybean oil

AbstractThe soy polyols were prepared from epoxidation of soybean oil followed by ring opening of oxirane obtained by using methanol as the ring opener. Polyols of hydroxyl (OH) numbers ranging from 128 to 174 mg of KOH/g were obtained by the variation of epoxidation time of soybean oil. A novel cast polyurethane resin has been synthesized by these polyols and 2,4‐toluene diisocyanate. Swelling of networks in toluene showed that the sol fraction varies from 1.13 to 72.06%. The thermal and mechanical properties of cast resins were characterized by differential scanning calorimetry and thermogravimetric analysis. The results showed that the glass transition temperature increases with the increase of OH number and that the thermal stability of the resins was slightly decreased with the increasing OH number. The tensile strength at break increases with the increase of OH number. Polyols with OH number of 174 mg of KOH/g gave glassy polymers, whereas those below this value gave rubbers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009