木质生物材料多元醇液化及其在聚氨酯中的应用

液化技术是近年来生物质材料高效增值利用领域的研究热点,用多元醇等有机溶剂能将难溶、难熔的木质生物材料转化为可流动、具有反应活性的液态物质,拓宽了木材的应用领域。液化产物可作为合成高分子树脂的原料,能部分替代来源于石化产品的聚酯或聚醚多元醇。综述了木质材料多元醇的液化方法、液化机理及液化产物在聚氨酯中的应用。     

Polyurethanes from benzene polyols synthesized from vegetable oils: Dependence of physical properties on structure

Asymmetric and symmetric aromatic triol isomers were synthesized from erucic acid. The pure asymmetric and symmetric triols were crosslinked with MDI into their corresponding polyurethane sheets. The physico‐chemical properties of these polyurethanes were studied by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis coupled with Fourier transform infrared (TGA‐FTIR) spectroscopy, and tensile analysis. The A‐PU and S‐PU demonstrated differences in their glass transition temperatures (T_g) and crosslinking densities. The difference in T_g of these polyurethanes could be explained by the differences in crosslinking densities, which could be related to the increase in steric hindrance, to the crosslinking MDI molecules, between adjacent hydroxyl groups of the asymmetric triol monomers. Overall, it was found that both polyurethanes had similar mechanical and thermal properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Flame-retarding materials—I. Syntheses and flame-retarding property of alkylphosphate-type polyols and corresponding polyurethanes

In this research, oligomeric polyalkyl phosphate-type polyols (P% = 14–17) were synthesized from ethylene glycol or 1,4-butanediol (PBE or PBB) by means of butyl phosphorodichloridate, which was prepared from phosphorus oxychloride and butanol. These polyols were then reacted with isocyanate to form the corresponding polyurethanes (PETD and PBTD). These polyols were characterized by FTIR, ¹H-NMR, and ³¹P-NMR, and the thermal stabililties were measured by thermogravimetry analysis. The degradation phenomena were traced by FTIR and interpreted in terms of the degradation and formation of bonds. The corresponding polyurethanes were also characterized by FTIR and ¹H-NMR, and their thermal stability was also studied by thermogravimetry analysis. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1635–1643, 1998     

双功能催化剂在纤维素制多元醇中的研究进展

双功能催化剂的研究一直是纤维素降解制备高值化学品过程中催化剂研究的热点问题,但其在催化纤维素降解过程中还存在着催化机理不明确、目标产物选择性不高、水热稳定性不好等问题。本文简述了目前最受关注的含Ru、Ni、W、Pt等体系的双功能催化剂和不同载体影响下的双功能催化剂在纤维素制备C₆多元醇、低碳多元醇(C₂~C₃)等化学品中的研究进展,初步总结了单金属、双金属体系和不同载体的双功能催化剂研究的前沿进展,分析表明不同活性金属之间配比以及活性金属与载体之间的相互作用均对催化效果产生重大影响;最后对其在纤维素制备多元醇中的应用前景进行了展望,指出继续研究活性金属之间及其与载体之间的相互作用将是今后研究的重点方向。     

Click‐ligation of coumarin to polyether polyols for polyurethane foams

A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry     

Production of polyols and waterborne polyurethane dispersions from biodiesel‐derived crude glycerol

This study investigated the preparation of polyols and waterborne polyurethane dispersions (CG‐WPUDs) from biodiesel‐derived crude glycerol. The polyols were produced from biodiesel‐derived crude glycerol via a thermochemical conversion process, which converted crude glycerol components such as glycerol, free fatty acids, and methyl esters of fatty acids (FAMEs) into polyols under optimized reaction conditions. CG‐WPUDs with different hard segments (41.0% to 63.2 wt %) were prepared from the crude glycerol‐based polyols produced. PU coating films cast from CG‐WPUDs showed increasing glass transition temperatures (T_g) from 63°C to 81°C when hard segment content increased from 41.0% to 63.2% and had good thermal stability up to 240°C. CG‐WPUD‐based coatings showed excellent adhesion to steel panel surfaces, pencil hardness as high as F, but relatively low flexibility. This study demonstrated the potential of biodiesel‐derived crude glycerol for the production of bio‐based polyols and WPUDs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41425.     

马来酸酐改性油酸基聚酯多元醇的合成

以油酸为原料,经羟基化、酸酐改性、酯化合成油酸基聚酯多元醇,考察了摩尔比、常压反应温度时间、减压反应温度时间、催化剂用量等因素对酯化反应的影响,研究了不同组合酯化试剂对多元醇性能的影响。采用红外光谱(FT-IR)、高效凝胶色谱(GPC)、热重(TGA)对多元醇的结构、相对分子质量、热稳定性进行了表征。结果表明,最佳酯化条件为醇酸比n(二甘醇)∶n(羟基油酸)=1.1∶1,催化剂Zn O量为0.8%,常压、210℃下反应90min,再在180℃下减压反应120min。     

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.     

聚醚多元醇新型催化剂的技术经济分析

概述了聚醚多元醇新型催化剂的研制背景 ,描述了新技术的创新点及优势 ,对年产 5 0t新型催化剂装置进行了经济分析     

Preparation of polyester polyols from unsaturated fatty acid

Oleic acid is a typical unsaturated fatty acid that is found widely in vegetable oils. The objective of this investigation was to produce a new type of oleic‐based polyol from oleic acid. Possible advantages of this approach include the production of high‐performance polyurethane materials from renewable resources and value‐added research for oleic acid. Oleic‐based polyols were synthesized by a three‐step process consisting of epoxidation and ring‐opening reaction, followed by esterification. The synthesized polyols appeared as a viscous liquid at room temperature with hydroxyl numbers from 307 to 425 mg KOH/g. Preparation of polyurethane foams using oleic‐based polyols and isocyanate was studied. An environmentally friendly blowing agent, HCFC‐141b, together with a small amount of water, was used. The synthesized foams were characterized by FTIR, SEM, and TG/DSC. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Flexible polyurethane foams modified with biobased polyols: Synthesis and physical‐chemical characterization

A series of flexible polyurethane foams with different polyol compositions were synthesized through the replacement of a portion of the petroleum‐based polyether polyol with biobased polyols, namely, glycerol (GLY) and hydroxylated methyl esters (HMETO). HMETO was synthesized by the alkaline transesterification of tung oil (TO; obtaining GLY as a byproduct) and the subsequent hydroxylation of the obtained methyl esters with performic acid generated in situ. FTIR spectroscopy, ¹H‐NMR, and different analytical procedures indicated that the hydroxyl content increased significantly and the molecular weight decreased with respect to those of the TO after the two reaction steps. The characterization of the obtained foams, achieved through the measurement of the characteristic reaction times, thermal and dynamic mechanical analysis, scanning electronic microscopy, and density measurements, is reported and discussed. The most important changes in the modified foams were found with the addition of GLY to the formulation; this led to an increased foam density and storage rubbery modulus, which were associated with a higher crosslinking density because of the decrease in the chain length between crosslinking points. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43831.     

Polyols and polyurethane foams from acid‐catalyzed biomass liquefaction by crude glycerol: Effects of crude glycerol impurities

The effects of crude glycerol impurities on acid‐catalyzed biomass liquefaction by crude glycerol were investigated. Salts (i.e., NaCl and Na₂SO₄) decreased biomass conversion ratios and negatively affected the properties of polyols produced. Regression models were developed and validated as appropriate for describing the relationships between organic impurities and biomass conversion ratios and between organic impurities and the hydroxyl number of polyols. Polyols produced from crude glycerol containing 0–45% organic impurities showed the hydroxyl number varying from 1301 to 700 mg KOH/g, acid number from 19 to 28 mg KOH/g, viscosity from 2.4 to 29.2 Pa s, and molecular weight (M_w) from 244 to 550 g/mol. Crude glycerol containing 40–50 wt % of organic impurities was suitable to produce polyols with suitable properties for rigid and/or semi‐rigid polyurethane (PU) foam applications. The produced PU foams showed density and compressive strength comparable to those derived from petrochemical solvent‐based liquefaction processes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40739.     

聚醚多元醇工业现状分析

介绍了聚醚多元醇的分类用途及其生产原料,分析了国内外聚醚多元醇的生产概况及聚醚多元醇工业面临的挑战。     

低不饱和度聚醚多元醇PU弹性体性能的影响因素

探讨室温固化低不饱和度聚氧化丙烯醚多元醇PU弹性体性能的影响因素。结果表明，预聚体中游离-NCO质量分数为O．08时，PU弹性体的固化速度快，综合物理性能较好；低不饱和度聚氧化丙烯醚多元醇的官能度和相对分子质量大，PU弹性体强伸性能好；相对分子质量为3000的低不饱和度聚氧化丙烯醚二醇／低不饱和度聚氧化丙烯醚三醇并用体系PU弹性体综合性能较好；扩链剂为MOCA、催化剂为醋酸苯汞的PU弹性体颜色较浅。     

Hyperbranched polyols from hydroformylated methyl soyate

Hydroformylation of methyl soyate produces a mixture of fatty acid methyl esters with zero, one, two, and three hydroxyl groups, the major component being with two hydoxyls (around 50%). Polymerization of methyl esters of hydroxy fatty acids gives a hyperbranched product with a different content of hydroxyl groups depending on the degree of conversion. Molecular weights can be controlled by controlling the degree of conversion but also using monofunctional components. A range of hyperbranched polyols with acceptable viscosities and functionalities, suitable for flexible applications, was obtained by stopping the reaction at varying degrees of conversion. Monte-Carlo simulation of the polymerization of hydroxylated methyl soyate gave molecular weights and polydispersity which were compared with experimental values. Although hydroxylated methyl soyate contains considerable amounts of mono- and difunctional fatty acids, the system produces a physical gel at the highest conversions. This is due to very high molecular weights and was confirmed by experiments and the simulation. The simulation unexpectedly gave lower molecular weights but wider distribution than the experiments. This discrepancy was explained by the combination of experimental difficulties and possible side reactions leading to higher molecular weights. Functionality of polyols determined from gel points at critical NCO/OH ratios was reasonably close to predictions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Green polyurethane from dimer acid based polyether polyols: Synthesis and characterization

In this study, dimer acid (DA) obtained from waste soybean oil was used together with propylene oxide (PO) to obtain novel polyether polyols [prepolymers for polyurethanes (PUs)] through ring‐opening polymerization reaction. The average molecular weight of polyols was estimated by gel permeation chromatography and titration method. The substantial reaction between DA and PO was evident from FTIR and nuclear magnetic resonance spectroscopy. Subsequently, the polyols were reacted with chain extender [ethylene glycol, (EG)] and 4, 4 ‐ Diphenylmethane diisocyanate (MDI) to prepare green PUs. The effect of molar ratio variation of EG and MDI with a fixed amount of polyols was estimated by measuring hydrophobicity and mechanical strength of PUs. The molar ratio such as 1 : 4 : 5.7 of polyol : EG : MDI was found to exhibit maximum hydrophobicity and improved mechanical strength that were comparable with typical PU sample prepared from commercially available polyol, such as polypropylene glycol. FTIR spectroscopic analysis confirmed the chemical changes and possible crosslinking in PUs. Thermalgravimetric analysis and differential scanning calorimetry analysis also showed substantial thermal stability of the green PUs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41410.     

氨基树脂制备聚脲多元醇

将三聚氰胺进行改性制备氨基树脂即多元胺溶液,再将氨基树脂用于制备聚脲多元醇(PHD),并对其合成原理、合成工艺及其关键影响因素等进行了研究。用红外光谱、NDJ-1型旋转式黏度计、LG10-24型离心机、透射电镜(TEM)、热重分析(TG)等对聚脲分散体进行测试与表征。     

聚合物多元醇中的稳定剂

简要介绍了聚合物多元醇中稳定剂的作用原理、合成方法及其对聚合物多元醇产品质量的影响。     

Sequential liquefaction of Nicotiana tabacum stems biomass by crude polyhydric alcohols for the production of polyols and rigid polyurethane foams

In this work, Nicotiana tabacum stalks and castor oil‐based polyol was synthesized via two step process. Preliminarily, stalks were liquefied using acid catalyst to procure glycol‐glycoside and the optimized conditions for liquefaction of N. tabacum stem's biomass was 150 °C temperature for 180 min time using PTSA as catalyst. Progressively, the glycol‐glycoside obtained from the former step was further reacted with castor oil in the presence of lithium hydroxide to get dark brown‐colored polyol with hydroxyl value was running in between 200 and 400 I_OH. Glycol‐glycoside and polyols were characterized by chemical and instrumental methods. Further by employing open‐cup method involving the mixing of polyol and isocyanate adducts, the desired poly urethane rigid foam was obtained. The product was tested for their physical, mechanical, thermal, and morphological characteristics, while the thermal conductivity was in the range of 0.013 to 0.017 Kcal/mh °C. The performed study may yield high quality rigid or semi‐rigid polyurethane foams that are commonly used as insulation materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43974.     

Kinetic modelling of the pyrolysis of biomass and biomass components

The kinetics of the pyrolysis of lignocellulosic materials was studied with a view of providing simple kinetic models for engineering purposes. Experimental data obtained by means of thermal analysis techniques suggest that the pyrolysis of fine particles (below 1 mm) can be considered to be controlled by pyrolysis kinetics. The rate of pyrolysis of one biomass type can be represented by the sum of the corresponding rates of the main biomass components (cellulose, lignin, hemicellulose). The kinetics of each of these components was simulated by a kinetic scheme capable of predicting the pyrolysis rate and the final weight-loss for a wide range of pyrolysis parameters including various heating conditions.