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The Oxyalkylation of Hydrophilic Black Alder Bark Extractives with Propylene Carbonate with a Focus on Green Polyols Synthesis
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作者 Alexandr Arshanitsa Matiss Pals +1 位作者 Daniela Godina Oskars Bikovens 《Journal of Renewable Materials》 EI CAS 2024年第11期1927-1948,共22页
The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and l... The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and lowtoxic base-catalyzed modification with propylene carbonate(PC).FTIR spectroscopy,HP-LC,GC,GPC,and wet chemistry methods were used to characterize the starting constituents,intermediate and final products of the reaction and to monitor the different pathways of PC conversion.The reaction of extractives as well as the model compounds,including catechol,xylose,PEG 400,and benzoic acid,with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC.The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain,obtained as a result of remaining PC homopolymerization.The domination of the oxypropylation mechanism vs.transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes,making the process of oxypropylation with PC similar to that of conventional oxypropylation.At optimal reaction conditions,including a PC/OH ratio of 3.0 and a 24-h duration at 150°C,uniform polyols with low viscosity of~900 mPa·s^(-1),a biomass content of~27%,and an OHV of~500 mg KOH·g^(-1) were obtained.Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity.At fixed temperature values,increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing.The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology. 展开更多
关键词 Bark extractives propylene carbonate OXYALKYLATION polyols
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Promotion of Ni/MCM-41 Catalyst for Hydrogenation of Naphthalene by co-Impregnation with Polyols
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作者 仇松柏 翁育靖 +3 位作者 李玉萍 马龙隆 张琦 王铁军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期433-438,J0001,共7页
The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydrogenation of naphthalene. Compare... The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydrogenation of naphthalene. Compared with the conventional wetness impregnation, addition of moderate polyols into the metal nitrate support surface, resulting in formation of persion of the active phase and significant aqueous solution could enhance interaction with very small NiO particle size (〈5 nm), high discatalytic activity. Particle size of Ni^0 decreased from 36.1 nm to below 5 nm; meanwhile the complete hydrogenation of naphthalene was dependent on the Ni^0 particle size. The hydrogenation activities of the catalysts prepared by co-impregnation with polyols were very high with 100% conversion even at iow temperature of 55 ℃. 展开更多
关键词 Ni/MCM-41 co-Impregnation Naphthalene hydrogenation polyols
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Preparation and characterization of tung oil-based flame retardant polyols 被引量:3
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作者 Wei Zhou Puyou Jia +1 位作者 Yonghong Zhou Meng Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2664-2671,共8页
Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycer... Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycerol by sodium methoxide. The products after transesterification were epoxidized by peracetic acid which was in-situ generated from acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst. And then, TOFPs were prepared from epoxidized alcoholysis tung oil(EGTO) with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO), diethyl phosphate(DEP) and diethanolamine(DEA) by ring-opening reactions, respectively. GPC was used to evaluate the conversion rate, at optimum reaction conditions, selectivity for monoglyceride in transesterification. The influence of different parameters such as temperature, mole ratio or mass ratio on the conversion rate of transesterification and epoxidation were investigated. The molecular structures of TOFPs were characterized by FTIR and ~1HNMR. Finally, tung oil-based polyurethane foams(TOPUFs) were prepared by a one-shot process using TOFPs with polyisocyanate. The LOI values of TOPUFs whose content of DOPO-EGTO,DEP-EGTO and DEA-EGTO were 100 wt% can reach to 26.2%, 25.1%, and 24.4%, respectively. 展开更多
关键词 Tung OIL TRANSESTERIFICATION EPOXIDATION FLAME retardant polyols
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Self-reducing bifunctional Ni-W/SBA-15 catalyst for cellulose hydrogenolysis to low carbon polyols 被引量:4
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作者 Zhuqian Xiao Qiuwei Ge +4 位作者 Chuang Xing Chengjun Jiang Sheng Fang Jianbing Ji Jianwei Mao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第3期434-444,共11页
A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized using biomass-based carbon source as the reducing agent without conventional further reduction step. The self-reducing catalysts were perfo... A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized using biomass-based carbon source as the reducing agent without conventional further reduction step. The self-reducing catalysts were performed on the hydrogenolysis of cellulose to low carbon polyols. The effects of calcination temperature and metallic loading contents for cellulose hydrogenolysis reaction were investigated detailedly.The optimal calcination temperature was found to be 673 K by TG analysis. The active metal nanoparticles with a better dispersion were observed using SEM and element mapping technology. The yield of low carbon polyols using the catalyst with the receipt of 10%Ni-15%W/SBA-15-673 K can reach as high as68.14%, of which the ethylene glycol(EG) accounts for 61.04%. 展开更多
关键词 Cellulose HYDROGENOLYSIS Low carbon polyols Self-reducing catalyst
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Ehealth monitoring in irritable bowel syndrome patients treated with low fermentable oligo-, di-, mono-saccharides and polyols diet 被引量:7
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作者 Natalia Pedersen Zsuzsanna Vegh +5 位作者 Johan Burisch Lisbeth Jensen Dorit Vedel Ankersen Maria Felding Nynne Nyboe Andersen Pia Munkholm 《World Journal of Gastroenterology》 SCIE CAS 2014年第21期6680-6684,共5页
In the present study we report on changes in irritable bowel syndrome-severity scoring system (IBS-SSS) and irritable bowel syndrome-quality of life (IBS-QoL) in 19 IBS patients, aged 18 to 74 years (F/M: 14/5), durin... In the present study we report on changes in irritable bowel syndrome-severity scoring system (IBS-SSS) and irritable bowel syndrome-quality of life (IBS-QoL) in 19 IBS patients, aged 18 to 74 years (F/M: 14/5), during 12 wk registering their symptoms on the web-application (www.ibs.constant-care.dk). During a control period of the first 6-wk patients were asked to register their IBS-SSS and IBS-QoL on the web-application weekly without receiving any intervention. Thereafter, low fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet (LFD) was introduced for the next 6 wk while continuing the registration. Though a small sample size a significant improvement in disease activity (IBS-SSS) was observed during both the control period, median: 278 (range: 122-377), P = 0.02, and subsequently during the LFD period, median: 151 (range: 29-334), P &#x0003c; 0.01. The IBS-QoL solely changed significantly during the LFD period, median: 67 (37-120), P &#x0003c; 0.01. The significant reduction in disease activity during the control period shows a positive effect of the web-application on IBS symptoms when presented as a &#x0201c;traffic light&#x0201d;. However adding the diet reduced IBS-SSS to &#x0003c; 150, inactive to mild symptoms. In the future results from larger scale trials are awaited. 展开更多
关键词 Irritable bowel syndrome Low fermentable oligo- di- mono-saccharides and polyols diet SELF-MANAGEMENT Disease-specific quality of life Disease activity
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Catalytic Conversion of Biomass-Derived Polyols into Para-xylene over SiO2-Modified Zeolites 被引量:2
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作者 Sheng-fei Wang Ming-hui Fan +1 位作者 Yu-ting He Quan-xin Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第4期513-520,I0003,共9页
This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromat... This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts. 展开更多
关键词 Biomass-derived polyols PARA-XYLENE Catalytic conversion SiO2-modified HZSM-5
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Directional assist (0 1 0) plane growth in LiMnPO_(4) prepared by solvothermal method with polyols to enhance electrochemical performance 被引量:1
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作者 Qian Xie Jihua Zhu +5 位作者 Chengyun Wang Kaibin Fang Wei Yang Quanbing Liu Yali Wang Shengzhou Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期181-189,共9页
Phosphate material LiMnPO4 is popular for its high energy density(697 W·h·kg^(-1))and safety.When LiMnPO_(4) crystal grows,the potential barrier along b and c axis is strong,which makes the crystal grow alon... Phosphate material LiMnPO4 is popular for its high energy density(697 W·h·kg^(-1))and safety.When LiMnPO_(4) crystal grows,the potential barrier along b and c axis is strong,which makes the crystal grow along b axis to form a one-dimensional chain structure.However,the main migration channel of lithium ions in olivine structure is plane(010).By shortening the growth in the direction of b axis and enhancing the diffusion along the directions of a and c,two-dimensional nanosheets that are more conducive to the migration of lithium ions are formed.The dosage of polyols is the key factor guiding the dispersion of the crystals to the(010)plane.X-ray diffraction(XRD),Scanning electron microscopy(SEM),transmission electron microscopy(TEM)and other means are used to characterize the samples.After experiments,we found that when the ratio of polyol/water was 2:1,the morphology of the synthesized sample was 20–30 nm thick nanosheets,which had the best electrochemical performance.At 0.1C,the discharge specific capacity reaches 148.9 mA·h·g^(-1),still reaches 144.3 mA·h·g^(-1) at the 50th cycle.and there is still 112.5 mA·h·g^(-1) under high rate(5C).This is thanks to the good dispersion of the material in the direction of the crystal plane(010).This can solve the problem of low conductivity and ionic mobility of phosphate materials. 展开更多
关键词 LMnPO_(4) polyols Lithium-ion battery Phosphate material Crystal
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Catalytic conversion of glucose to small polyols over a binary catalyst of vanadium modified beta zeolite and Ru/C
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作者 Joby Sebastian Mingyuan Zheng +3 位作者 Xinsheng Li Jifeng Pang Chan Wang Tao Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期88-95,共8页
Catalytic conversion of glucose, the most abundant carbohydrate, to chemicals of petroleum origin has great desirability in terms of sustainability and industrial implementation. In this work, we attempted to exploit ... Catalytic conversion of glucose, the most abundant carbohydrate, to chemicals of petroleum origin has great desirability in terms of sustainability and industrial implementation. In this work, we attempted to exploit the vanadium-based catalysts with high retro-aldol condensation(RAC) activity for the synthesis of small polyols from glucose. Vanadium species incorporated or anchored beta zeolites were found to work effectively in synergy with 1 Ru/AC to produce hydroxyacetone(HA) as the major product(34%)in a semi-continuously stirred tank reactor under 5% glucose concentration. Catalyst characterization by UV-vis and Raman spectral analysis revealed vanadium species mainly stayed in the incorporated form(tetrahedral) at 0.5% of loading and in the supported form(octahedral) at higher loadings up to 8%. Pyridine infrared spectra and temperature programmed desorption of NH3 revealed weak Lewis acid sites in dominance. Vanadium species in the catalysts displayed multiple catalytic roles(isomerization and RAC reaction, and synergism with the hydrogenation catalyst) in the synthesis of HA from glucose. Structureactivity correlation pointed out that the catalytic activity of vanadium species is not dependent on it coordination status, nevertheless, the adjacent vanadium atoms could possibly improve the isomerization rate over the RAC rate in favor of high yield of HA. The catalyst system is recyclable to at least five times without any considerable loss in its activity and structural integrity. The results presented here provide a promising route for the sustainable production of HA and polyols from carbohydrates by using a highly selective vanadium catalyst. 展开更多
关键词 VANADIUM GLUCOSE Retro-aldol condensation polyols HYDROXYACETONE
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Low fermentable oligosaccharides, disaccharides,monosaccharides, and polyols diet in children
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作者 Ioana Fodor Sorin Claudiu Man Dan L Dumitrascu 《World Journal of Clinical Cases》 SCIE 2019年第18期2666-2674,共9页
Irritable bowel syndrome (IBS) is a lifelong condition with a high prevalence among children and adults. As the diet is a frequent factor that triggers the symptoms, it has been assumed that by avoiding the consumptio... Irritable bowel syndrome (IBS) is a lifelong condition with a high prevalence among children and adults. As the diet is a frequent factor that triggers the symptoms, it has been assumed that by avoiding the consumption of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP), the symptoms might be improved. Therefore, in the past decade, low FODMAP diet has been intensively investigated in the management of IBS. The capacity of FODMAPs to trigger the symptoms in patients with IBS was related to the stimulation of mechanoreceptors in the small and large intestine. This stimulation appears as a response to a combination of increased luminal water (the osmotic effect) and the release of gases (carbon dioxide and hydrogen) due to the fermentation of oligosaccharides and malabsorption of fructose, lactose and polyols. Numerous studies have been published regarding the efficacy of a low FODMAP diet compared to a traditional diet in releasing the IBS symptoms in adults, but there are only a few studies in the juvenile population. The aim of this review is to analyze the current data on both low FODMAP diet in children with IBS and the effects on their nutritional status and physiological development, given the fact that it is a restrictive diet. 展开更多
关键词 Low fermentable OLIGOSACCHARIDES DISACCHARIDES MONOSACCHARIDES polyols DIET CHILDREN Irritable bowel syndrome Symptom
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Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU) 被引量:1
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作者 Saeed Kazemi Najafi Farhood Najafi +2 位作者 Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz 《Journal of Renewable Materials》 SCIE EI 2023年第5期2171-2190,共20页
Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and carbon-hydrogen.These compounds are mainly used as reactants to make other polymers.Amon... Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and carbon-hydrogen.These compounds are mainly used as reactants to make other polymers.Among biopolymers,lignin is regarded as the base of a new polymer in polyol construction.The present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the environment.To this aim,first,lignin was extracted from raw liquor.Next,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene carbonate.The results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified lignin.Moreover,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR analysis.Additionally,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample. 展开更多
关键词 polyol LIGNIN DIETHYLENETRIAMINE ETHYLENEDIAMINE propylene carbonate polyurethanes NIPU
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Physico-mechanical characterization of polyurethane foam dressings containing natural polyols
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作者 Nantaporn Namviriyachote Kitipun Manosittisak Garnpimol C.Ritthidej 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期114-115,共2页
Advanced wound dressings are replaced traditional dressings in order to provide appropriate environment for healing and also to promote cell migration[1].The key characteristics of wound dressings are non-toxic,highly... Advanced wound dressings are replaced traditional dressings in order to provide appropriate environment for healing and also to promote cell migration[1].The key characteristics of wound dressings are non-toxic,highly absorbed,air permeable,biocompatible and have good mechanical properties[2].Due to providing moist environment and also protecting maceration at the wound edge area,foam dressings are used in various clinical applications[3].They are mostly prepared from polyurethane between polyols and isocyanate polymerization. 展开更多
关键词 POLYURETHANE foam NATURAL polyols STARCH Physico-mechanical properties
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Surface Functionalization of Microporous Polypropylene Membrane with Polyols for Removal of Boron Acid from Aqueous Solution
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作者 周蓉 狄玲 +3 位作者 王苍 方艳 吴健 徐志康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第1期11-18,共8页
Affinity membranes are fabricated for boric acid removal by the surface functionalization of microporous polypropylene membrane(MPPM)with lactose-based polyols.The affinity is based on specific complexation between bo... Affinity membranes are fabricated for boric acid removal by the surface functionalization of microporous polypropylene membrane(MPPM)with lactose-based polyols.The affinity is based on specific complexation between boric acid and saccharide polyols.A photoinduced grafting-chemical reaction sequence was used to prepare these affinity membranes.Poly(2-aminoethyl methacrylate hydrochloride)[poly(AEMA)]was grafted on the surfaces of MPPM by UV-induced graft polymerization.Grafting in the membrane pores was visualized by dying the cross-section of poly(AEMA)-grafted MPPM with fluorescein disodium and imaging with confocal laser scanning microscopy.It is concluded that lactose ligands can be covalently immobilized on the external surface and in the pores by the subsequent coupling of poly(AEMA)with lactobionic acid(LA).Physical and chemical properties of the affinity membranes were characterized by field emission scanning electron microscopy and Fourier Transform Infrared/Attenuated Total Refraction spectroscopy(FT-IR/ATR).3-Aminophenyl boric acid(3-APBA)was removed from aqueous solution by a single piece of lactose-functionalized MPPM in a dynamic filtration system.The results show that the 3-APBA removal reaches an optimal efficiency(39.5%)under the alkaline condition(pH9.1),which can be improved by increasing the immobilization density of LA.Regeneration of these affinity membranes can be easily realized through acid-base washing because the complexation of boric acid and saccharide polyol is reversible. 展开更多
关键词 surface functionalization affinity membrane microporous polypropylene membrane boron removal polyols
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Time-dependent radiolytic yields at room temperature and temperature-dependent absorption spectra of the solvated electrons in polyols
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作者 Mingzhang LIN Mehran MOSTAFAVI +2 位作者 Yusa MUROYA Isabelle LAMPRE Yosuke KATSUMURA 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第1期2-9,共8页
The molar extinction coefficients at the absorption maximum of the solvated electron spectrum have been evaluated to be 900,970,and 1000 mol^(-1).m^2 for 1,2-ethanediol (12ED),1,2-propanediol (12PD),and 1,3-propanedio... The molar extinction coefficients at the absorption maximum of the solvated electron spectrum have been evaluated to be 900,970,and 1000 mol^(-1).m^2 for 1,2-ethanediol (12ED),1,2-propanediol (12PD),and 1,3-propanediol (13PD),respectively.These values are two-third or three-fourth of the value usually reported in the published report. Picosecond pulse radiolysis studies have aided in depicting the radiolytic yield of the solvated electron in these sol- vents as a function of time from picosecond to microsecond.The radiolytic yield in these viscous solvents is found to be strongly different from that of the water solution.The temperature dependent absorption spectra of the solvated electron in 12ED,12PD,and 13PD have been also investigated.In all the three solvents,the optical spectra shift to the red with increasing temperature.While the shape of the spectra does not change in 13PD,a widening on the blue side of the absorption band is observed in 12ED and 12PD at elevated temperatures. 展开更多
关键词 多羟基化合物 溶剂化电子 时间相关性辐射分解 室温 温度相关性吸收谱
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木质素低聚物衍生聚氨酯泡沫的制备及性能 被引量:1
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作者 霍淑平 刘贵锋 +3 位作者 霍美玉 金灿 吴国民 孔振武 《工程塑料应用》 CAS CSCD 北大核心 2024年第4期23-28,共6页
针对木质素分子结构复杂、反应活性低、高值化利用不足等问题,从木质素高效可控降解、分子结构定向化学修饰以及复合功能化等方面出发,开展了木质素可控氢化降解以及基于木质素低聚物衍生聚氨酯泡沫(PUFs)材料的制备及性能调控研究。以N... 针对木质素分子结构复杂、反应活性低、高值化利用不足等问题,从木质素高效可控降解、分子结构定向化学修饰以及复合功能化等方面出发,开展了木质素可控氢化降解以及基于木质素低聚物衍生聚氨酯泡沫(PUFs)材料的制备及性能调控研究。以Ni/ZrO_(2)/Hβ为催化剂,对木质素进行部分还原降解获得了高酚羟基含量的活性木质素低聚物,继而经氧丙基化改性,制备了高反应活性的木质素低聚物多元醇(LOP),通过^(31)P NMR和^(1)H NMR表征分析了木质素低聚物及LOP,探讨了木质素低聚物改性前后的结构变化。将LOP与大豆油多元醇复配构建了全生物基PUFs材料,考察了LOP的结构及用量等对PUFs材料的微观结构、形貌及其物理化学性能的作用与影响规律,探明了不同性能木质素低聚物衍生PUFs材料的制备工艺。研究结果表明,LOP的加入会导致PUFs材料的泡孔减小,闭孔率增加,进而有效改善PUFs力学性能和高温热稳定性,通过对LOP用量的调节,可实现不同强度PUFs的高效制备(压缩强度0.27~0.65 MPa)。 展开更多
关键词 木质素 低聚物 多元醇 聚氨酯 泡沫
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Preparation and Properties of Vegetable-Oil-Based Thioether Polyol and Ethyl Cellulose Supramolecular Composite Films
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作者 Ruyu Yan Jian Fang +7 位作者 Xiaohua Yang Na Yao Mei Li Yuan Nie Tianxiang Deng Haiyang Ding Lina Xu Shouhai Li 《Journal of Renewable Materials》 SCIE EI 2023年第4期1937-1950,共14页
Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes i... Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes it too brittle to be used widely.The hydroxyl group on EC can form a supramolecular system in the form of a non-covalent bond with an effective plasticizer.In this study,an important vegetable-oil-based derivative named dimer fatty acid was used to prepare a novel special plasticizer for EC.Dimer-fatty-acid-based thioether polyol(DATP)was synthesized and used to modify ethyl cellulose films.The supramolecular composite films of DATP and ethyl cellulose were designed using the newly-formed van der Waals force.The thermal stability,morphology,hydrophilicity,and mechanical properties of the composite films were all tested.Pure EC is fragile,and the addition of DATP makes the ethyl cellulose films more flexible.The elongation at the break of EC supramolecular films increased and the tensile strength decreased with the increasing DATP content.The elongation at the break of EC/DATP(60/40)and EC/DATP(50/50)was up to 40.3%and 43.4%,respectively.Noticeably,the thermal initial degradation temperature of the film with 10%DATP is higher than that of pure EC,which may be attributed to the formation of a better supramolecular system in this composite film.The application of bio-based material(EC)is environmentally friendly,and the novel DATP can be used as a special and effective plasticizer to prepare flexible EC films,making it more widely used in energy,chemical industry,materials,agriculture,medicine,and other fields. 展开更多
关键词 Ethyl cellulose dimeric fatty acid based thioether polyol supramolecular system composite films
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聚氨酯涂料废弃物的化学降解及其资源化利用化
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作者 李国华 方学镇 +2 位作者 沈祝 张欣宇 王静娴 《中国塑料》 CAS CSCD 北大核心 2024年第3期79-85,共7页
以一缩二乙二醇作为醇解剂对聚氨酯涂料废弃物进行醇解,回收低分子量的多元醇,并将再生多元醇与商用多元醇混合作为原料制备再生聚氨酯泡沫。采用FTIR、GPC、TG及SEM等对再生多元醇及再生聚氨酯泡沫进行了分析测试表征,对再生多元醇及... 以一缩二乙二醇作为醇解剂对聚氨酯涂料废弃物进行醇解,回收低分子量的多元醇,并将再生多元醇与商用多元醇混合作为原料制备再生聚氨酯泡沫。采用FTIR、GPC、TG及SEM等对再生多元醇及再生聚氨酯泡沫进行了分析测试表征,对再生多元醇及再生聚氨酯泡沫进行表征分析。通过正交试验获得了最优工艺参数,并进一步将再生多元醇与商用多元醇混合,验证其性能。结果表明,再生多元醇与聚醚多元醇在分子结构上具有一致性,且符合制备聚氨酯泡沫的性能要求;正交试验获得的最优工艺参数为:反应试剂比1∶2,反应温度180℃,反应时间2 h,催化剂添加量1.3%,在此条件下,醇解产物的提取率为36.8%,羟值为384.6 mgKOH/g,黏度为476 mPa·s;当再生多元醇在总多元醇中的比例为33%时,所制备聚氨酯具有良好的孔隙结构及热稳定性。 展开更多
关键词 聚氨酯 涂料 醇解 多元醇 回收 再生
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双组分聚氨酯-聚脲涂料的制备与性能研究 被引量:1
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作者 孔磊 吴昆鹏 +2 位作者 刘鑫 谭志勇 张会轩 《化工新型材料》 CAS CSCD 北大核心 2024年第4期152-155,160,共5页
采用异佛尔酮二异氰酸酯(IPDI)、不同比例的聚醚二醇(N-220)和聚醚三醇(N-330)与固化剂4,4′-亚甲基双(2-氯苯胺)(MOCA)制备双组分聚氨酯-聚脲(PUU)复合涂料。研究了合成预聚体的适宜反应条件、异氰酸酯指数(R值)、软段中两种聚醚多元... 采用异佛尔酮二异氰酸酯(IPDI)、不同比例的聚醚二醇(N-220)和聚醚三醇(N-330)与固化剂4,4′-亚甲基双(2-氯苯胺)(MOCA)制备双组分聚氨酯-聚脲(PUU)复合涂料。研究了合成预聚体的适宜反应条件、异氰酸酯指数(R值)、软段中两种聚醚多元醇的比例对涂料性能的影响。通过二正丁胺法、红外光谱(FT-IR)、拉伸强度、接触角、差示扫描量热法(DSC)、扫描电镜(SEM)对涂层进行了分析。结果表明:78℃左右体系反应时间最短,得到的涂料体系稳定。预聚体中R值增加,涂膜的断裂强度增大,断裂应变减小,R=4时,涂膜有良好力学性能。当n(聚醚二醇)∶n(聚醚三醇)=1∶1时,聚氨酯涂料的综合性能最好;n(聚醚二醇)∶n(聚醚三醇)=3∶1时接触角最大;玻璃化转变温度逐渐升高。 展开更多
关键词 聚醚多元醇 双组分 4 4′-亚甲基双(2-氯苯胺) 涂料
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Polyol合成法制备生物医药用超小粒径Fe_3O_4磁性纳米晶体 被引量:6
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作者 刘红玲 吴君华 《化学研究》 CAS 2008年第3期9-13,共5页
采用一罐polyol合成法还原Fe(Ⅲ)乙酰丙酮化合物制备了粒径可调、单分散、直径5nm以下的磁性Fe3O4纳米晶体.其晶粒表面为所用聚合物表面活性剂PVP所包覆.运用透射电镜/高分辨透射电镜、X射线衍射、振动样品磁强计和超导量子干涉仪对其... 采用一罐polyol合成法还原Fe(Ⅲ)乙酰丙酮化合物制备了粒径可调、单分散、直径5nm以下的磁性Fe3O4纳米晶体.其晶粒表面为所用聚合物表面活性剂PVP所包覆.运用透射电镜/高分辨透射电镜、X射线衍射、振动样品磁强计和超导量子干涉仪对其结构和性能进行了表征.结果表明所制得的Fe3O4磁性纳米晶体在室温下显示出优良的超顺磁性,且结晶度高、分散性好、化学性质稳定同时表面易修饰.磁滞回线的模型分析说明该Fe3O4纳米晶粒是磁性单畴.该法制得的超顺磁Fe3O4纳米晶粒在生物和医学领域具有重要的应用价值. 展开更多
关键词 polyol合成法 超小粒径 FE3O4 尺寸控制
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阻燃剂对喷涂聚脲弹性体阻燃性能的影响 被引量:1
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作者 刘晓文 岳长山 +3 位作者 谷晓昱 张沪伟 薛鑫 王宝柱 《聚氨酯工业》 CAS 2024年第1期26-29,共4页
选用阻燃剂次磷酸铝(AHP)、石墨(EG)、含磷多元醇按不同用量添加到喷涂聚脲弹性体(PUA)中,采用喷涂制样的方式制备阻燃聚脲,并探究了阻燃剂的种类及用量对聚脲热稳定性能和阻燃性能的影响。结果发现:AHP和EG的引入均能提高PUA的初始热... 选用阻燃剂次磷酸铝(AHP)、石墨(EG)、含磷多元醇按不同用量添加到喷涂聚脲弹性体(PUA)中,采用喷涂制样的方式制备阻燃聚脲,并探究了阻燃剂的种类及用量对聚脲热稳定性能和阻燃性能的影响。结果发现:AHP和EG的引入均能提高PUA的初始热分解温度和成炭性,含磷多元醇的引入会降低初始分解温度,对成炭性影响不大;通过石墨与含磷多元醇质量比1∶1复配会降低热释放速率和总释热量,改善成炭性和抑烟效果,LOI值可提高至29.2%,可达到UL94 V-0等级,阻燃性能优异。 展开更多
关键词 喷涂聚脲 次磷酸铝 石墨 含磷多元醇 阻燃性能
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微波辅助polyol法制备的纳米镍颗粒 被引量:4
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作者 徐小兵 刘先松 +2 位作者 Udi Meridor Aviad Frydman Aharon Gedanken 《磁性材料及器件》 CAS CSCD 2008年第6期33-35,共3页
采用微波辅助polyol还原法制备了单分散的纳米Ni颗粒。分别用X射线衍射(XRD)和透射电镜(TEM)观测样品的相结构和微观形貌,用振动样品磁强计(VSM)测试Ni颗粒的磁性。XRD显示样品为面心立方结构,TEM观察显示金属镍颗粒的形貌是理想的球型... 采用微波辅助polyol还原法制备了单分散的纳米Ni颗粒。分别用X射线衍射(XRD)和透射电镜(TEM)观测样品的相结构和微观形貌,用振动样品磁强计(VSM)测试Ni颗粒的磁性。XRD显示样品为面心立方结构,TEM观察显示金属镍颗粒的形貌是理想的球型。当把反应温度提高到400℃,并且在实验过程中加入适量的PVP时,发现镍颗粒呈现出一种毛茸茸的多毛形态,这种分散均匀的单一态形貌类似于纳米头发的结构。同时,VSM测试结果表明球型纳米Ni颗粒具有典型的铁磁性。 展开更多
关键词 单分散Ni球 微波辅助polyol还原法 结构 磁性
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