Polyurethane networks from polyols obtained by hydroformylation of soybean oil

BACKGROUND: Vegetable oil‐based polyols are a new class of renewable materials. The structure of oil‐based polyols is very different from that of petrochemical polyols, and it is closely related to the structure of oils. The objective of this work was to analyze the structural heterogeneity of soy‐based polyols and its effect on the properties of polyols and polyurethanes. RESULTS: A series of polyols with a range of hydroxyl numbers were prepared by hydroformylation and partial esterification of hydroxyls with formic acid. Polyols were reacted with diphenylmethane diisocyanate to obtain polyurethanes of different crosslinking density. Gelation was simulated using the Monte Carlo method with a calculated distribution of functionalities for each polyol. CONCLUSIONS: Most polyols are powerful crosslinkers since weight average functionality varied from 5 to 2.5 resulting in gel points from 53 to 83% conversion. Heterogeneity of polyols had a negative effect on mechanical properties of rubbery polyurethanes and this should be taken in account when designing polyols for flexible applications. This effect was not pronounced in glassy polyurethanes. Copyright © 2007 Society of Chemical Industry     

Characterization and comparison of polyurethane networks prepared using soybean‐based polyols with varying hydroxyl content and their blends with petroleum‐based polyols

Polyurethane Networks (PUNs) were synthesized using polyols derived from soybean oil, petroleum, or a blend of the two in conjunction with diisocyanate. The soybean‐based polyols (SBPs) were prepared using air oxidation, or by hydroxylating epoxidized soybean oil. Some of the networks were subjected to several solvents to determine their respective swelling behavior and solubility parameters. Sol‐fractions were also determined, and DMA experiments were utilized to monitor the changes in storage modulus and tan δ with temperature for networks with sol and with the sol extracted. A linear relationship was noted between the hydroxyl number of a SBP and the glass transition temperature of its corresponding unextracted PU network within the range of hydroxyl numbers (i.e., 55–237 mg KOH/g) and glass transition temperatures (i.e., ?21–+83°C) encountered in this work. This same linear relationship was realized between the weighted hydroxyl number of soy and petroleum‐based polyol blends and the glass transition temperature of the resulting unextracted and extracted network PUs within the ranges utilized in this study (i.e., 44–57 mg KOH/g, ?54–19°C). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1432–1443, 2006     

Rigid polyurethane foams made from high viscosity soy‐polyols

This study investigated the physical properties of water‐blown rigid polyurethane (PU) foams made from VORANOL®490 (petroleum‐based polyether polyol) mixed with 0–50% high viscosity (13,000–31,000 cP at 22°C) soy‐polyols. The density of these foams decreased as the soy‐polyol percentage increased. The compressive strength decreased, decreased and then increased, or remained unchanged and then increased with increasing soy‐polyol percentage depending on the viscosity of the soy‐polyol. Foams made from high viscosity (21,000–31,000 cP) soy‐polyols exhibited similar or superior density‐compressive strength properties to the control foam made from 100% VORNAOL® 490. The thermal conductivity of foams containing soy‐polyols was slightly higher than the control foam. The maximal foaming temperatures of foams slightly decreased with increasing soy‐polyol percentage. Micrographs of foams showed that they had many cells in the shape of sphere or polyhedra. With increasing soy‐polyol percentage, the cell size decreased, and the cell number increased. Based on the analysis of isocyanate content and compressive strength of foams, it was concluded that rigid PU foams could be made by replacing 50% petroleum‐based polyol with a high viscosity soy‐polyol resulting in a 30% reduction in the isocyanate content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Polyurethane networks from formiated soy polyols: Synthesis and mechanical characterization

Polyurethanes can be prepared using polyols obtained from vegetable oils in natura, such as castor oil, or from functionalized vegetable oils, such as hydroxylated soybean oil. These polyurethanes have different valuable properties, determined by their chemical composition and cross-linking density. In this study, soy epoxy polyols with different OH contents were prepared through a one-step reaction using the method of in situ performic acid generation. Polyols with OH functionalities from 1.9 to 3.2 were reacted in bulk with different diisocyanates at a NCO/OH molar ratio of 0.8 and 60°C for 24 h. Mechanical properties of the polyurethanes were determined by dynamic mechanical thermal analysis, hardness (Shore A), and swelling measurements. Polymer networks with glass-transition temperatures (T _g ) from −13 to 48°C were obtained. We observed that the higher the OH functionality of the polyols, the higher the T _g and cross-linking density of the polyurethane network. The influence of diisocyanate structure (rigid or flexible chain), curing temperature, and curing reaction time on mechanical properties was also investigated.     

Rigid polyurethane foams based on soybean oil

Both HCFC‐ and pentane‐blown rigid polyurethane foams have been prepared from polyols derived from soybean oil. The effect of formulation variables on foam properties was studied by altering the types and amounts of catalyst, surfactant, water, crosslinker, blowing agent, and isocyanate, respectively. While compressive strength of the soy foams is optimal at 2 pph of surfactant B‐8404, it increases with increasing the amount of water, glycerin, and isocyanate. It also increases linearly with foam density. These foams were found to have comparable mechanical and thermoinsulating properties to foams of petrochemical origin. A comparison in the thermal and thermo‐oxidative behaviors of soy‐ and PPO‐based foams revealed that the former is more stable toward both thermal degradation and thermal oxidation. The lack of ether linkages in the soy‐based rather than in PPO‐based polyols is thought to be the origin of improved thermal and thermo‐oxidative stabilities of soy‐based foams. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 467–473, 2000     

Physical properties of water‐blown rigid polyurethane foams from vegetable oil‐based polyols

Fifty vegetable oil‐based polyols were characterized in terms of their hydroxyl number and their potential of replacing up to 50% of the petroleum‐based polyol in waterborne rigid polyurethane foam applications was evaluated. Polyurethane foams were prepared by reacting isocyanates with polyols containing 50% of vegetable oil‐based polyols and 50% of petroleum‐based polyol and their thermal conductivity, density, and compressive strength were determined. The vegetable oil‐based polyols included epoxidized soybean oil reacted with acetol, commercial soybean oil polyols (soyoils), polyols derived from epoxidized soybean oil and diglycerides, etc. Most of the foams made with polyols containing 50% of vegetable oil‐based polyols were inferior to foams made from 100% petroleum‐based polyol. However, foams made with polyols containing 50% hydroxy soybean oil, epoxidized soybean oil reacted with acetol, and oxidized epoxidized diglyceride of soybean oil not only had superior thermal conductivity, but also better density and compressive strength properties than had foams made from 100% petroleum polyol. Although the epoxidized soybean oil did not have any hydroxyl functional group to react with isocyanate, when used in 50 : 50 blend with the petroleum‐based polyol the resulting polyurethane foams had density versus compressive properties similar to polyurethane foams made from 100% petroleum‐based polyol. The density and compressive strength of foams were affected by the hydroxyl number of polyols, but the thermal conductivity of foams was not. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

大豆油基聚氨酯的研究及应用进展

综述了大豆油基聚氨酯的制备方法及应用,以大豆油为绿色原料,通过环氧化得到环氧大豆油,利用环氧大豆油开环制得大豆油基多元醇,再用此多元醇与异氰酸酯反应得到大豆油基聚氨酯泡沫、大豆油基聚氨酯乳液以及溶剂型大豆油基聚氨酯树脂。同时介绍了大豆油基聚氨酯在泡沫、涂料、胶粘剂等领域的具体应用。     

Synthesis of aminophosphonate polyols and polyurethane foams with improved fire retardant properties

Aminophosphonated polyols with flame retardant properties are synthesized by ring opening polymerization using diethyl-N,N-bis(2-hydroxyethyl) aminomethyl phosphonate (Fyrol-6) as initiator. The influence of the catalyst type and its concentration on the polymerization rate are studied. The catalyst system formed by potassium methoxide (MeOK) in DMSO as a solvent presents the highest polymerization rate and allows reducing the polydispersity. The thermal resistance of the synthesized polyols is confirmed by the char residues formation. Finally, PU foams are synthesized containing up to a 50 pph of PFyCs[1:1], preserving good cellular structure up to a 25 pph content and improving the fire resistance by increasing the char residue from 7.79 to 22.13 wt % and decreasing the PHRR and the smoke production according to TGA and cone calorimeter tests, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47780.     

Polyurethane foams made from liquefied bark‐based polyols

Liquefaction is known to be an effective method for converting biomass into a polyol. However, the relationships between bark liquefaction conditions and properties of the resulting foams are unclear. In this study, polyurethane foams (PUF) were made using bark‐based polyols obtained through liquefaction reactions of bark at two different temperatures (90 and 130°C). Through systematic characterization of the PUFs the influence of the liquefied bark and liquefaction conditions on foam properties could be observed. The bark‐based foams had similar foaming kinetics, thermal stability, and glass transition temperatures compared with the PEG‐based control foam. The bark‐based PUF from the polyol obtained at the higher liquefaction temperature showed comparable specific compressive strength to the PEG‐based control foam. Lastly, both bark foams exhibited a high amount of open‐cell content, with the foam made from the lower temperature liquefied polyol having poor cell morphology. This deviation from the controls in the open‐cell content may explain the lower modulus values observed in the bark PUFs due to the lack of cell membrane elastic stretching as a strengthening mechanism. These results demonstrated the influence of the bark liquefaction conditions on foam properties, thereby providing a better fundamental understanding for the practical application of bark‐based PUFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40599.     

Desaminated glycolysis of water‐blown rigid polyurethane foams

Glycolysis reaction kinetics of methylene diphenyl diisocyanate‐based water‐blown polyurethane foams was examined by gel permeation chromatography. Glycolysates were reacted with butyl glycidyl ether to convert toxic aromatic amines to polyols, and their products were identified by ¹H‐NMR spectroscopy. To examine the quality of recycled polyol, polyurethane foams were reprepared using the virgin and recycled polyol mixtures with varying compositions. Cell structures and sizes of reprepared foams were similar to those of original ones when the recycled polyols were mixed up to 30 wt %. Density, thermal conductivity, and flexural strength of the reprepared foams were compared with those of the original ones, and no difference was observed below the recycled polyol concentration of 30 wt %. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2646–2656, 2000     

Nanofilled polyols for viscoelastic polyurethane foams

The use of polyether polyols is common in polyurethane industry, particularly in soft PU applications. In particular, viscoelastic foams, characterized by slow recovery after compression, are obtained using poly(ethylene oxide) (PEO) polyols. Nanofilled polyols can be used for the production of viscoelastic foams with improved fire resistance properties. The high polarity of polyether polyols is responsible of a poor affinity with the organic modifiers used in commercial organically modified montmorillonite (omMMT). In this work, organically modified montmorillonites were prepared, having an improved affinity with the polyether polyols used for the production of soft PU foams. The montmorillonite was modified by using polyetheramines with different ethyleneoxide/propyleneoxide amounts. A strongly intercalated/exfoliated structure was obtained after mixing the polyol with the omMMT. The viscosity increased by three orders of magnitude and the diffraction angles of the MMT measured by x‐ray analysis decreased to values lower than 1.5°. The intercalated structure was preserved after the curing stage, when the isocyanate was added to the polyol/omMMT. The resulting polyurethane had an irregular open cell structure, and was characterized by a mechanical properties comparable to those of unfilled polyurethane. Copyright © 2009 Society of Chemical Industry     

Effect of different rapeseed-oil-based polyols on mechanical properties of flexible polyurethane foams

Two rapeseed-oil-based polyols were synthesized by partial epoxidation of the double bonds in fatty acid chains and overall opening oxirane rings by using diethylene glycol. Flexible polyurethane foams with varied isocyanate index and modified by partial substitution of petrochemical polyether triol with rapeseed-oil-derived polyols were obtained. Bio-polyols: Polyol I and Polyol II differed in functionalities (2.5 and 5.2, respectively) and hydroxyl values (114 and 196 mg KOH/g, respectively). Influence of the bio-polyols on mechanical properties, resilience, apparent density, and cellular structure of synthesized foams was investigated. Compression properties were examined and compared via determining compression values and compression stress—strain characteristics, as well as tensile strength and elongation at break were estimated. Foams modified with Polyol I had higher values of resilience and elongation at break than those with Polyol II, while higher tensile and compression strength and superior cell structure were observed in the case of foams modified with Polyol II. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

聚合物填充改性多元醇合成技术及应用的研究进展

介绍了聚合物填充改性多元醇技术的发展概况,并综述了聚合物多元醇、聚氨酯多元醇和聚脲多元醇等填充多元醇的研究进展。     

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     

The study of palm‐oil‐based bio‐polyol on the morphological,acoustic and mechanical properties of flexible polyurethane foams

The focus of this paper was to explore the acoustic properties of flexible polyurethane (FPU) foam modified by palm‐oil‐based polyol (POP). The presence of POP showed a marked influence on the microstructure and mechanical properties of FPU foam. A smaller mean pore diameter can be observed at lower POP content. Indeed, the introduction of POP caused a higher closed pore ratio and an increased air‐flow resistivity, which consequently improved the sound absorption coefficient and transmission loss. In particular, the acoustic performance of the all bio‐based FPU foam was enhanced at low frequency, and the density was lower than that of the reference foam. Additionally, the addition of POP also improved the compressive strength. Conversely, the tensile strength of FPU foam declined with increasing POP content. From this study, the outstanding acoustic ability of bio‐based FPU foam has been proved, with additional advantages of lower density and higher compressive strength. © 2019 Society of Chemical Industry     

Thermal and mechanical behavior of flexible polyurethane‐molded plastic films and water‐blown foams with epoxidized soybean oil

Water‐blown flexible polyurethane foams and molded plastic films were made by replacing 0 to 50% of Voranol® 4701 in the B‐side of foam and plastic film formulation by epoxidized soybean oil (ESBO). Physical properties of foams including density, 50% compression force deflection (CFD), 50% constant deflection compression (CDC), and resilience were determined. A dynamic mechanical spectrometer (DMS) and a differential scanning calorimeter (DSC) were used to characterize the hard segment (HS) and soft segment (SS) ratio and thermal properties of plastic. Various functional groups in both flexible polyurethane foam and plastic film were characterized using Fourier transform‐infrared spectroscopy with attenuated total reflectance (FTIR‐ATR). When increasing the ESBO content, both density and 50% CFD of water‐blown polyurethane foams decreased first, then increased. On the other hand, the 50% CDC and resilience of foams showed a sharp increase and decrease, respectively. When increasing the ESBO content, the peak of tan δ in DMS analysis and Δc_p in DSC analysis of plastic films both decreased indicating the hard segment increased and the soft segment decreased in plastic film, respectively. The FTIR‐ATR results also show the hydrogen‐bonded urethane group increased in plastic films with increasing ESBO content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and properties of multihydroxy soybean oil from soybean oil and polymeric methylene‐diphenyl‐ 4,4′‐diisocyanate/multihydroxy soybean oil polyurethane adhesive to wood

The reactive multihydroxy soybean oil (MHSBO) was synthesized from epoxidized soybean oil (ESBO). The ESBO was reacted with ethylene glycol to obtain MHSBO having high functionality. This study investigated a feasibility to prepare wood adhesive through the reaction of polymeric methylene‐diphenyl‐4,4′‐diisocyanate (pMDI) with MHSBO. Different polyurethane adhesives were prepared with a variety of equivalent mole ratios (eq. mole ratios) of MHSBO to pMDI. The chemical reactions of adhesives were analyzed using ¹H NMR and Fourier transform infrared (FTIR), and their thermal studies were investigated by DSC and TGA. The MHSBO/pMDI resins (3 : 1 and 2 : 1 eq. mole ratios) showed endothermic peaks, whereas the MHSBO/pMDI resins (1 : 2 and 1 : 3 eq. mole ratios) showed exothermic peaks. The best adhesion strength was found when plywood was bonded with the adhesive of a eq. mole ratio of 2 : 1 (MHSBO : pMDI). These results indicated that the bond strength was not related to the reactivity obtained from the FTIR spectra. But it was explained that the adhesion strength increased as the residual  NCO groups in the adhesive reacted with the hydroxy groups of wood during the manufacturing of plywood. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚合物多元醇GPOP-H45制备高回弹泡沫研究

采用新型高活性聚合物多元醇GPOP-H45为原料,制备出机械性能良好的高回弹泡沫制品。讨论了影响泡沫性能的主要因素及国外同类产品发泡情况和制品性能的比较。结果发现,在发泡中加入GPOP-H45,可显著提高泡沫制品的承载性及开孔性,同时改进了其机械性能。     

Characterization of flexible polyurethane foams based on soybean‐based polyols

Two series of flexible polyurethane foams were fabricated by substituting conventional petroleum‐based polyols with increasing amounts of soy‐based polyols (SBP) having different hydroxyl numbers. The mechanical properties of the foams were characterized by stress–strain analysis in the compression mode and DMA in tension mode, the cellular morphology was analyzed by SEM and the microphase‐separation of the foams was noted by SAXS. Our results showed that the cellular morphology and mechanical properties of the flexible foams were affected significantly by the foam fabrication method and SBP hydroxyl numbers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Physical properties of water‐blown rigid polyurethane foams containing epoxidized soybean oil in different isocyanate indices

To explore the potential of isocyanate usage reduction, water‐blown rigid polyurethane foams were made by replacing 0, 20, and 50% of Voranoll® 490 in the B‐side of the foam formulation by epoxidized soybean oil (ESBO) with an isocyanate index ranging from 50 to 110. The compressive strength, density, and thermal conductivity of foams were measured. The foam surface temperature was monitored before and throughout the foaming reaction as an indirect indication of the foaming temperature. Increasing ESBO replacement and/or decreasing isocyanate index decreased the foam's compressive strength. The density of the foam decreased while decreasing the isocyanate index to 60. Further decrease in isocyanate index resulted in foam shrinkage causing a sharp increase in the foam density. The thermal conductivity of foams increased while decreasing the isocyanate index and increasing the ESBO replacement. Mathematical models for predicting rigid polyurethane foam density, compressive strength, and thermal conductivity were established and validated. Similar to compressive strength, the foaming temperature decreased while decreasing the isocyanate index and increasing the ESBO replacement. Because of the lower reactivity of ESBO with isocyanate, the rate of foaming temperature decrease with decreasing isocyanate index was in the order of 0% > 20% > 50% ESBO replacement. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009