Soybean Oil-based Polyol Research Articles

Improved thermal stability and flame retardancy of soybean oil-based polyol rigid polyurethane foams modified with magnesium borate hydroxide and ammonium polyphosphate

The concept of sustainable development has led to a growing research interest in bio-based flame-retardant polyurethane foams. These foams offer environmentally friendly, sustainable, and flame-retardant raw materials for the construction, automotive, and furniture industries. The 15 wt% soybean oil-based polyol rigid polyurethane foams (RPUF-S3A20B system) were modified with 20 wt% ammonium polyphosphate (APP) and homemade magnesium borate hydroxide (MgBO2(OH)). Thermogravimetric analysis, pyrolysis kinetic analysis, limiting oxygen index (LOI) test, cone calorimetry (CONE), morphological analysis, and smoke density (Ds) were employed to investigate the impact of MgBO2(OH) on the thermal stability and flame-retardant properties of the RPUF-S3A20B system. The results indicated that RPUF-S3A20B12.5 with 12.5 wt% MgBO2(OH) had better thermal stability and higher activation energy. In addition, its LOI was increased by 3.1% compared to RPUF-S3A20 without MgBO2(OH). The peak heat release rate (PHRR) and total heat release rate (THR) of RPUF-S3A20B12.5 at a radiant flux of 25 kW/m2 were reduced by 45.8% and 35.0% compared with RPUF-S3A20. RPUF-S3A20B12.5 demonstrated the lowest smoke density (17.4 and 17.5) and highest light transmission (73.9% and 73.7%) in both flameless and flame conditions, indicating superior flame-retardant and smoke-suppression properties. These findings offered valuable insights for further research on synergistic flame-retardant systems in bio-based polyurethane foams.

Fabrication of nickel phytate modified bio-based polyol rigid polyurethane foam with enhanced compression-resistant and improved flame-retardant

A bio-based flame retardant nickel phytate (PA-Ni) was synthesized and combined with soybean oil-based polyol (SO) to create a green rigid polyurethane foam (RPUF) with enhanced compressive strength, good thermal stability and flame retardant. The results showed that the RPUF-SO2/Ni3 with 3 wt% PA-Ni had the highest initial and termination temperature, maximum thermal decomposition rate temperature and carbon residue, and better thermal stability. Its limiting oxygen index was increased by 2.6% compared with RPUF-SO2 without PA-Ni added, and the peak heat release rate (PHRR) and total heat release rate (THR) were reduced by 14.92% and 19.92%, respectively. In addition, RPUF-SO2/Ni3 had the lowest Ds under the conditions of flame (18.90) and flameless (22.41), and had the best smoke suppression effect. And the compressive strength of RPUF-SO/Ni3 was significantly enhanced by the addition of PA-Ni. The results show that the improvement of flame retardancy of RPUF is mainly the result of the combined effect of gas-phase and condensed-phase flame retardancy, among which the flame retardancy of RPUF-SO/Ni3 was the best. The current findings offer a practical way to produce green and low-carbon RPUF as well as promising prospects for the material's safe application.

Exploring Soybean Oil-Based Polyol and the Effect of Non-halogenated Flame Retardants in Rigid Polyurethane Foam

Exploring Soybean Oil-Based Polyol and the Effect of Non-halogenated Flame Retardants in Rigid Polyurethane Foam

The role of Zinc Molybdate in the anticorrosion and antibacterial characteristics of sustainable polyurethane coating derived from epoxidized soybean oil

Vegetable oils are important renewable sources that have been used as alternative feedstocks to petroleum for the synthesis of polyols. Polyols are compounds that contain multiple hydroxyl groups in a molecule and are a major component of polyurethanes. One of the oldest problems that many industries face today is corrosion. Polyurethane coatings reduce the rate of corrosion reactions but are not completely impermeable to corrosive agents. Nanoparticles, due to their high surface area and small particle size, can improve the performance of polyurethane coatings and block the penetration of corrosive agents. This research aims to prepare polyurethane coatings using soybean oil-based polyol and investigate the corrosion resistance performance of polyurethane coatings by adding Zinc Molybdate (ZnMoO4) nanoparticles. To achieve this goal, a polyol based on soybean oil was synthesized through the ring-opening reaction of Epoxidized soybean oil. Then, polyurethane coatings with 0.5, 1, 1.5, and 2 wt% of ZnMoO4 nanoparticles were prepared. Characterization of the polyurethane coatings was performed using FTIR, HNMR, and FESEM. The mechanical properties were also examined. Finally, the corrosion resistance activity of these nanocomposites was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The results showed that adding 0.5%w/w of ZnMoO4 nanoparticles can improve the performance of polyurethane coatings against corrosion, as the nanoparticles were uniformly dispersed on the surface of the coating and blocked the penetration of corrosive agents. Therefore, 0.5 wt% ZnMoO4 nanoparticles can be considered as the optimal amount in this experiment. Moreover, the modified coating with ZnMoO4 nanoparticles can effectively act against both gram (+) and gram (-) bacteria.

Role of crosslinkers on the properties of bio‐based wood adhesives

AbstractAs people became more conscious of the risks associated with pollution in the early 21st century, eco‐friendly adhesives made from plant oil began to be used. Bio‐based adhesives are widely used due to their low price, easy accessibility, and high biodegradability; however, their low adhesive strength is an issue. This work incorporates three natural crosslinkers: tannic acid (TA), sorbitol (SR), and cellulose (CL) to address the drawbacks of bio‐based adhesives, such as low adhesive strength, inferior output in humidity and longer curing time that result from excess water. Methylene diphenyl diisocyanate (MDI) was used to react with soybean oil‐based polyol (SOP) plus the crosslinkers to make bio‐based polyurethane adhesives. The maximum bonding strength of the soybean‐based adhesive containing 10 wt.% of SR (SR‐10%) was measured at 6.19 MPa which is about 44% higher than the sample without SR. The higher strength is due to the crosslinking ability of SR. The effect of crosslinking is also observed in the study of polar protic and polar aprotic solvents used to dissolve the adhesive. As compared with the polar aprotic solvent tetrahydrofuran, TA‐containing adhesive samples showed a maximum tensile strength of 3.69 MPa in methanol; a polar protic solvent that can participate in further hydrogen bonding to form a higher crosslinked complex. The glass transition temperature (Tg) increases with the increase in crosslinker amount. The observed increase in Tg may be attributable to an increase in crosslinking density, which reduces polymer chain flexibility and causes a stronger material.Highlights Bio‐adhesives based on soybean oil and diisocyanate were synthesized. Natural crosslinking agents such as tannic acid, sorbitol, and cellulose were used. The effect of crosslinking using polar protic and aprotic solvents was studied. The glass transition temperature increases with the increase in crosslinker amount.

Fabrication of expandable graphite and soybean oil-based synergistic modified polyurethane foam with improved thermal stability and flame retardant properties

Abstract Biomass soybean oil-based polyol rigid polyurethane foam (RPUF) was modified and prepared by expandable graphite (EG). The effects of EG on the thermal stability and flame retardant properties of soybean oil-based polyol RPUFs were investigated by thermogravimetric analysis, pyrolysis kinetic analysis, conical calorimetry and flue gas toxicity analysis. The results showed that modified RPUF (RPUF-4) with EG content of 20 wt% had the highest initial and end temperatures, the highest activation energy E, the lowest Ds (17.6), and the highest light transmittance (73.6 %). At the same time, RPUF-4 had the lowest heat release rate (10.1 and 16.5 kW/m2), the lowest total heat release (1.5 and 2.1 MJ/m2), and the lowest average toxic gas emissions. The current study indicated that RPUF-4 had better thermal stability and flame retardant performance, which provided a useful reference for subsequent biomass flame retardant modified RPUFs.

Correction: Green Synthesis of Polyurethanes Using Soybean Oil-Based Polyols for Bioactive Functional Fabrics

Correction: Green Synthesis of Polyurethanes Using Soybean Oil-Based Polyols for Bioactive Functional Fabrics

Fabrication of soybean oil-based polyol modified polyurethane foam from ammonium polyphosphate and its thermal stability and flame retardant properties

Abstract Rigid polyurethane foams (RPUFs) were prepared using biomass soybean oil-based polyol and ammonium polyphosphate (APP) as raw materials. The effects of APP on the thermal stability and combustion performance of soybean oil-based polyol-modified RPUFs were investigated by thermogravimetric analysis, pyrolysis kinetic analysis, limiting oxygen index (LOI) test, cone calorimetry (CONE), scanning electron microscopy (SEM), and smoke density (Ds). The results showed that the modified RPUF with 20 wt% APP (RPUF-S3-20) had the lowest mass loss, the highest integrated programmed decomposition temperature and the highest activation energy. In addition, RPUF-S3-20 had the lowest Ds (30.9), the highest light transmittance (61.4 %), the lowest heat release rate (602.7 kW/m2, 506.8 MJ/m2, and 847.3 kW/m2) and the total heat release (18.3 MJ/m2, 21.4 MJ/m2, and 31.4 MJ/m2), which showed that RPUF-S3-20 had good thermal stability and flame retardant performance. The current results can provide an effective reference for the preparation of environmentally friendly RPUF by bio-based modification.

The thermal and combustion properties of soybean oil phosphate-based polyurethane foam composites containing polyol of etidronic acid

In this work, a phosphorus-containing soybean oil-based polyol (PSOP) was successfully synthesized from epoxidized soybean oil by a ring-opening reaction with dibutyl phosphate. A phosphorous polyol (HEDP-PO) was synthesized by polymerization between 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and propylene oxide (PO). The two new polyols were used together in the formation of flame-retardant polyurethane foams (FRPUF), which depicted good thermal stability and flame retardancy performance. The addition of PSOP/HEDP-PO polyols resulted in a reduction of cell size and an increasement of cell numbers of PUF composites, whose apparent density was observed to increase. Besides, the LOI value of PUF-80 could reach 23.7% and satisfy the V-0 rating in the vertical burning test. The cone calorimeter test showed a reduction in the heat release rate from 395 kW/m2 to 251 kW/m2 and the total heat release from 24.9 MJ/m2 to 18.0 MJ/m2. Polyurethane foam exhibited good flame retardancy because PSOP/HEDP-PO played a great free radical quenching effect in the gas phase by releasing the PO* and PO2* free radicals. Meanwhile, a more dense and complete carbon layer was formed to cut off the transfer of heat and oxygen between the matrix and the ambient.

Synthesis, Characterization and Properties of Soybean Oil-Based Polyurethane.

At present, the consumption of polyurethane is huge in various industries. As a result, it has become a research hotspot to use environmentally friendly and renewable bio-based raw materials (instead of petroleum-based raw materials) to prepare polyurethane. In this paper, epoxy soybean oil (ESO) was used as raw material, and polyethylene glycol (PEG-600) was used for ring opening. Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) analysis proved that soybean oil-based polyester polyols was prepared. Soybean oil-based polyurethane (SPU) was synthesized by the reaction of the soybean oil-based polyol with isophorone diisocyanate (IPDI), so as to save energy and protect the environment. The properties of SPU films were adjusted by changing the R value (the molar ration of -NCO/-OH) and the film forming temperature. The chemical structure and properties of the SPU were characterized by FTIR, 1H NMR, gel permeation chromatography (GPC), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results show that the mechanical strength, water contact angle, microphase separation degree, barrier property, and thermal stability of SPU films gradually increase, while the transparency, oxygen permeability coefficient and moisture permeability coefficient of SPU films gradually decrease with the increase of R value and film forming temperature.

Synthesis and characterization of different soybean oil-based polyols with fatty alcohol and aromatic alcohol

Abstract In this article, five kinds of soybean oil-based polyols (polyol-E, polyol-P, polyol-I, polyol-B, and polyol-M) were prepared by ring-opening the epoxy groups in epoxidized soybean oil (ESO) with ethyl alcohol, 1-pentanol, isoamyl alcohol, p-tert-butylphenol, and 4-methoxyphenol in the presence of tetrafluoroboric acid as the catalyst. The SOPs were characterized by FTIR, 1H NMR, GPC, viscosity, and hydroxyl numbers. Compared with ESO, the retention time of SOPs is shortened, indicating that the molecular weight of SOPs is increased. The structure of different monomers can significantly affect the hydroxyl numbers of SOPs. Due to the large steric hindrance of isoamyl alcohol, p-hydroxyanisole, and p-tert-butylphenol, SOPs prepared by these three monomers often undergo further dehydration to ether reactions, which consumes the hydroxyl of polyols, thus forming dimers and multimers; therefore, the hydroxyl numbers are much lower than polyol-E and polyol-P. The viscosity of polyol-E and polyol-P is much lower than that of polyol-I, polyol-B, and polyol-M. A longer distance between the molecules and the smaller intermolecular force makes the SOPs dehydrate to ether again. This generates dimer or polymers and makes the viscosity of these SOPs larger, and the molecular weight greatly increases.

External surfactant-free waterborne polyurethane grafted fluorine-containing acrylic copolymer with high hardness and low water absorption using chlorinated soybean oil-based urethane acrylate as polyol

In this work, a novel soybean oil-based urethane acrylate polyol called ADSO was synthesized by the condensation reaction of hydroxyethyl acrylate modified isophorone diisocyanate with chlorinated soybean oil (SOL). The soybean oil-based waterborne polyurethane called ADSO-WPU was prepared with SOL and ADSO as polyols. Using the carbon-carbon double bonds of ADSO-WPU as reaction sites, methyl methacrylate (MMA), butyl methacrylate (BA) and 2-(perfluorohexyl)ethyl methacrylate (PFOMA) were grafting copolymerized to obtain the soybean oil-based waterborne polyurethane grafted fluorine-containing acrylate (ADSO-PUA). The results of Fourier transform infrared spectrometer, dynamic light scattering analyzer and transmission electron microscopy showed that the grafted copolymer latex was successfully prepared with particle size of about 100–300 nm. Furthermore, effects of the ratio of PFOMA, MMA and BA on properties of grafted copolymer films were studied. Compared with ADSO-WPU film, ADSO-PUA film had significantly lower water absorption, higher hardness, better mechanical properties and higher thermal stability. With the increase of PFOMA content, the water absorption rate decreased from 108% to about 10%, the hardness increased from 4H to 6H, and the tensile strength increased from 3.05 MPa to 9.79 MPa.

Soybean Oil-based Polyol as a Modified Natural Binder for Polyurethane Turf-adhesive

Polyurethane turf adhesive is a two-component system formed by reacting diisocyante and petroleum-based polyether polyol. This polyol can be replaced by soybean oil as one of the main economical and common oils. In this article, soybean oil was epoxidized followed by oxirane ring-opening in the presence of methyl alcohol and orthophosphoric acid as a catalyst in order to create hydroxyl groups in the soybean oil which are responsible for reaction with the diisocyanate molecules. The epoxidation step was confirmed by ATR-FTIR spectroscopy and iodine value measurements. Iodine value was decreased from 135.6 g/100 g of neat soybean oil to be 5.98 g/100 g of epoxidized soybean oil. In addition, the effect of orthophosphoric acid contents (0.6%, 0.8%, 1.0%, 1.2%) on the ring-opening steps was investigated, considering the same reaction time, the same alcohol concentration and constant temperature. Successful oxirane ring-opening was confirmed by oxirane oxygen content (OOC) values which were decreased from 6.72% to 2.93%, 1.45%, 0.60% & 0.04% respectively. Hydroxyl value of oil-based polyols (OHV) were increased from 131, 180, 208 & 229 mg KOH/g respectively. Meanwhile, ATR-FTIR showed disappearance of the oxirane rings and appearance of hydroxyl groups as indication of polyol formation in the four samples. The four polyol samples were applied as modified natural binders in polyurethane turf adhesive formulations and showed comparable results against the standard and commercially used product SubFix 411.

Preparation of degradable vegetable oil-based waterborne polyurethane with tunable mechanical and thermal properties

In this study, the fully degradable soybean oil-based waterborne polyurethanes (SWPU) were prepared, and the mechanical properties, thermal properties and hydrophilicity of SWPU films were adjusted by changing the R value. First, soybean oil-based polyol was fabricated via epoxy soybean oil and ricinoleic acid in the absence of solvent and catalyst. Then, the resulting polyol was mixed with isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), trimethylamine (TEA) and ethylenediamine (EDA) to synthesize polyurethane emulsion with different R value (the molar ration of –NCO/–OH). The result showed that as the R value increased, the tensile strength of SWPU film was increased from 10.02 to 27.32 MPa, the initial decomposition temperature of polyurethane films was improved from 201 ℃ to 246 ℃, the Tg,h was increased from 68 to 130 ℃ and the water contact angle of SWPU films were enhanced from 82.4° to 95.5°. It can be explained that the degree of crosslinking of the polyurethane elastomer was improved and the interaction of the molecular chains became stronger with larger R value. Also, all SWPU films were placed in the 3 wt% sodium hydroxide solution at 45 ℃ to test the degradability, and the weight loss of samples at different degradation time were calculated, respectively. Finally, the morphology, FT-IR and tensile strength of samples was observed before and after degradation, and a possible mechanism of degradation was studied. The technique reported here demonstrated that it was possible to develop the degradable materials.

Vegetable oil-based polyurethanes as antimicrobial wound dressings: in vitro and in vivo evaluation

Preparation of efficient polyurethane-type wound dressings with tunable physicomechanical properties and widespread antimicrobial activity is considered in this work. A new type of soybean oil-based polyol with built-in urethane and quaternary ammonium groups is synthesized through a nonisocyanate route using carbonated soybean oil as an environmentally friendly, renewable resource-based raw material. Different formulations from this polyol and castor oil are prepared and converted to the polyurethane wound dressings via a reaction with isophorone diisocyanate. The dressing sample, with good cytocompatibility and efficient antimicrobial activity against various microbial strains, having tensile strength of 5 and 17 MPa at hydrated and dry state, elongation at the break of up to 400%, equilibrium water absorption and a water vapor transmission rate of 50% and 390 g m−2 day−1, is used for in vivo assay on a rat. Evaluation of the optimized dressing for a full-thickness non-sterilized wound has shown excellent progress of wound healing, since the tensile strength of regenerated skin reaches about 80% of normal healthy skin on day 21 after wounding. This has been significantly superior to the tensile strength of the regenerated skin of rats covered with non-antibacterial (∼50%) and cotton gauze (∼40%) dressings as blank and control groups.

Recycling of bio-polyurethane foam using high power ultrasound

Three different types of waste bio-polyurethane foams (bio-PUFs) made of castor oil-based polyol, castor oil-based polyol with isosorbide-based isocyanate, and soybean oil-based polyol were ultrasonically decrosslinked, and blended with a traditional PUF formula for fabrication of automotive seat cushions. The seating comfort of recrosslinked PUFs was quantified by calculating the hardness, hysteresis loss, and sag factor as derived from the indentation force deflection test, and found to exhibit improved seating comfort. In this regard, the ultrasonically decrosslinked bio-PUFs were examined by gel fraction, crosslink density, FT-IR spectroscopy, and thermal property, and the improvement of comfort was attempted to explain by analyzing the morphological changes of recrosslinked PUFs using SEM.

Controlled Hydroxyl Functionality of Soybean Oil-Based Polyols for Polyurethane Coatings with Improved Anticorrosion Properties

One of the major challenges in current polymer industry is to develop renewable and sustainable alternatives to petroleum-based raw materials. In this study, soybean oil (SO) was adopted as a renewable resource to afford polyols (MSO) with predetermined primary hydroxyl values (OHVs). The MSOs were prepared through a simple thiol-ene click reaction between the SO and 2-mercaptoethanol. The OHVs of the MSOs were adjusted simply by controlling the conversion of carbon-carbon double bonds of SO to OH groups. To explore their potential applications, series of polyurethane (PU) coatings were prepared from the MSOs. The MSOs with increased OHVs afforded PU coatings with higher glass transition temperature and improved adhesion strength values. Notably, increased OHVs of MSOs afforded PU coatings with improved anticorrosion properties in 3.5 wt% NaCl corrosive medium, which was attributed to the strong adhesion and blocking characteristics of the PU coatings. This study demonstrated that the number of hydroxyl functionality of the bio-based polyols played a crucial role in controlling the characteristics of the PU coatings.

Thermal properties of polyurethane elastomers from soybean oil-based polyol with a different isocyanate index

The aim of this work was to determine the influence of used soybean oil (SO)-based polyol on the thermal properties of tested polyurethane elastomers (PUEs), with a different value of isocyanate index (INCO). The thermal properties determined by thermogravimetric analysis and differential scanning calorimetry show that the highest INCO causes an increase in hydrogen bonds in PUEs and higher thermal stability. A structural analysis and degree of phase separation (DPS) of the tested PUEs were carried out via Fourier transform infrared spectroscopy. This analysis showed that at INCO = 1.02, the largest number of urethane bonds arises in PUE. The physicomechanical properties of PUEs were also tested via density, resilience, hardness, and wear resistance. The results concluded that the increasing number of –NCO groups during production of PUEs with SO polyol changes the number of hydrogen bonds and DPS and causes the increase of properties such as thermal resistance, storage modulus, cross-linking density, and wear resistance.

Functional soybean oil-based polyols as sustainable feedstocks for polyurethane coatings

The development of renewable and viable alternatives to petroleum-based polymeric materials is a major challenge to the long-term environmental and waste management issues of the polymer industry. In this study, a technology platform composed of a series of efficient and quantitative thiol-ene reactions for preparing functional and sustainable polyols is proposed. First, a soybean oil (SO)-based polyol with two hydroxyl groups (MSO) was synthesized through a controlled thiol-ene click reaction between SO and 2-mercaptoethanol. Second, other functional groups, such as silane, fluorine or ethylene oxide units, were introduced to the MSO through another thiol-ene reaction between the MSO and thiol-terminated intermediates to afford SO-based functionalized polyols. The thiol-terminated intermediates were obtained using a Michael addition reaction between dithiol- and methacrylate-terminated compounds. Employing silane-modified MSO (SiMSO) as a representative functionalized polyol, preparation of polyurethane (PU) coatings was demonstrated. For comparison, PU coatings with commercially available poly(propylene glycol) (PPG) and MSO were also prepared. The thermal, physico-mechanical and anticorrosion properties of the PU coatings clearly demonstrated that coatings made with the silane groups had a better performance. PU coatings with SiMSO exhibited higher hardness, Tg, and adhesion strength than the PU coatings with MSO and PPG. Notably, incorporation of SiMSO improved the anticorrosion properties of the PU coating in a 3.5 wt% aqueous NaCl solution, probably due to the improved blocking and adhesion properties of the coating on mild steel panel. The present study demonstrates SO-based functional polyols as promising alternatives to conventional polyols to afford PU coatings with desirable properties.

Flame retardant polyurethane foam prepared from compatible blends of soybean oil‐based polyol and phosphorus containing polyol

ABSTRACTA phosphorus containing polyether polyol (THPO‐PO) was synthesized by polymerization between tris(hydroxymethyl) phosphine oxide (THPO) and propylene oxide (PO). A soybean oil‐based polyol(SBP) was synthesized from epoxidized soybean oil by ring‐opening reaction with lactic acid. The corresponding polyurethane foams (PUFs) were prepared by mixing SBP with THPO‐PO. The density of these foams decreased as the content of THPO‐PO increased. The yield strength of PUFs was observed to be decreased firstly and then increased with the addition of THPO‐PO. Microphotographs of PUFs were examined by scanning electron microscope which displayed the cells as spherical or polyhedral. The thermal degradation and fire behavior of PUFs were investigated by thermogravimetric analysis, limiting oxygen index (LOI), and UL‐94 test. Although the thermal stability of PUFs were decreased with increasing THPO‐PO percentage, the flame retardancy of PUFs were improved. The LOI value increased to 27.5 with 40% THPO‐PO. THPO‐PO in sequence worked in inhibiting flame and forming phosphorus‐rich char layer, thus endowing PUFs with the increased flame‐retardant performance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45779.