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1.
蓖麻油型聚氨酯密封胶   总被引:3,自引:0,他引:3  
关键 《中国塑料》2000,14(2):25-32
阐述了蓖麻油型聚氨酯密封胶的性能与发展现状 ,分析了各种组分对密封胶性能的影响 ,并预测了此种密封胶的发展方向  相似文献   

2.
Castor oil can be used in industry. The molecular species of triacylglycerols containing hydroxy fatty acids (FA) in castor oil have been identified. We report here the identification of twelve diacylglycerols (DAG) containing hydroxy FA in castor oil using positive ion electrospray ionization mass spectrometry of the lithium adducts. They were RR (diricinolein, R is ricinoleate), RL, RS, R‐diOH18:0, R‐diOH18:1, R‐diOH18:2, R‐triOH18:0, R‐triOH18:1, R‐triOH18:2, diOH18:0‐diOH18:1, diOH18:1‐diOH18:1 and diOH18:1‐diOH18:2. The MS2 fragment ions, [M + Li ? FA]+ and [FA + Li]+, from the lithium adducts of DAG containing hydroxy FA (one or two hydroxy FA), were used for the identification. The additional fragment ions from the neutral losses of FA lithium salts [M + Li ? FALi]+ were used for the identification of eleven DAG containing two normal FA in a soybean oil bioconversion product. The MS2 fragment ions from the neutral losses of FA lithium salts [M + Li ? FALi]+ were not detected from the DAG containing hydroxy FA. The DAG containing FA with more hydroxyl groups than the other FA on the same DAG molecule tended to have a prominent fragment ion [FA + Li]+ and an undetectable fragment ion [M + Li ? FA]+ while the FA was the more hydroxylated FA. Also the less hydroxylated FA of a DAG tended to have a prominent fragment ion [M + Li ? FA]+ and an undetectable fragment ion [FA + Li]+ while the FA was the less hydroxylated FA.  相似文献   

3.
Cast polyurethanes based on castor oil, fluorescein and tolylene diisocyanate have been synthesized. The polyurethanes were characterized by Fourier transform infrared spectroscopy. The thermal stabilities of the polymers were determined using a thermogravimetric analyser. From the differential scanning calorimetric analysis, change in the glass transition temperature of the soft segment was observed as the molar ratio and feed composition of the fluorescein were varied. © 1997 SCI.  相似文献   

4.
李阳 《当代化工》2012,41(6):566-568
介绍了一种蓖麻油改性的环氧聚氨酯防腐蚀涂料、以蓖麻油改性异氰酸酯预聚物和环氧树脂为基料,以价格较为低廉的滑石粉、钛白粉、沉淀硫酸钡为颜填料制备了成本较低,件能较为优异的防腐蚀涂料.检测了优化条件下制备的涂料的性能.以蓖麻油改性环氧聚氨酯防腐蚀涂料和未经蓖麻油改件的环氧聚氨酯防腐蚀涂料进行防腐蚀性能对比,蓖麻油改性环氧聚氨酯防腐蚀涂料的耐酸、碱、盐水等防腐蚀性能更好.  相似文献   

5.
Although tremendous efforts have been dedicated to developing environmentally friendly bio-based waterborne polyurethane (WPU) dispersions from vegetable oil, the fabrication of WPU dispersions solely derived from vegetable oil-based polyol with excellent comprehensive properties is still challenging. In the present work, novel bio-based WPU dispersions derived from castor oil and soy polyol is successfully modified by phosphorus-nitrogen chain extender [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester (BH). The structure and properties of the dispersions and films are characterized systematically by Fourier transform infrared spectroscopy, thermogravimetric analysis , mechanical test, and limiting oxygen index (LOI), etc. The results indicate that bio-based WPU films display moderate mechanical performance by adjusting BH content, and the WPU film containing 100% BH with 47.8% biobased content has a tensile strength of 8 MPa and the highest Young's modulus of 62.3 MPa. The incorporation of BH can increase the production of char residue. The flame retardancy of WPU films increase gradually with the BH molar content, and the LOI value of the WPU100 with 1.53 wt% phosphorus content can reach as high as 28.1%. This work may provide a new approach to develop high biobased content, eco-friendly, flame retardant WPU for application in the surface coating industry.  相似文献   

6.
Castor oil and its three derivatives including methyl ricinoleate, sodium ricinoleate and ricinoleic acid were used as the raw material for alkali fusion to prepare sebacic acid. The reaction parameters including catalyst, ratio of oleochemicals/NaOH, reaction time and reaction temperature were optimized. It was found that Pb3O4 (1%) showed the best catalytic performance, and 553 K was considered as the most suitable reaction temperature. The oleochemicals/NaOH ratios of 15:14, 15:14, 15:12 and 15:14 were determined as the optimal ratio for alkali fusion of castor oil, methyl ricinoleate, sodium ricinoleate and ricinoleic acid, respectively. In addition, the optimal reaction time of alkali fusion of castor oil was 5 hours, and that of its derivatives was 3 hours. The maximum yield in sebacic acid of 68.8%, 77.7%, 80.1%, 78.6% can be obtained by using castor oil, methyl ricinoleate, sodium ricinoleate and ricinoleic acid as the raw material, respectively. High purity of sebacic acid was confirmed by GC and melting point analysis. ICP-OES results illustrated that the content of Pb in sebcic acid was less than 1 mg kg−1. Separating glycerol from castor oil was beneficial for alkali fusion, by which, the yield of sebacic acid was increased of approximately 10%, and the reaction time was reduced from 5 to 3 hours. This study provided guiding significance for the future industrial production of sebacic acid.  相似文献   

7.
Studies have been carried out on polyurethane elastomers based on modified castor oil in combination with different molecular weights of polyethylene glycol and polymeric methylene diphenyl-4,4′-diisocyanate (PMDI). The resulting polymers were cast into molds and the moldings were characterized by scanning electron microscopy and thermogravimetric analysis. Mechanical properties such as tensile strength, elongation at break, hardness, abrasion resistance, and compression set were measured. There is an increase in the flexibility of polyurethanes with increase in molecular weight of PEGs added to modified castor oil.  相似文献   

8.
Yongshang Lu  Patrice Dole 《Polymer》2005,46(23):9863-9870
A waterborne polyurethane (PU) aqueous dispersion was synthesized from castor oil, and blended with thermoplastic starch (TPS) to obtain a novel biodegradable plastic with improved physical properties. The effect of PU content on the morphology, miscibility and physical properties of the resulting blends was well investigated by scanning electron microscopy, differential scanning calorimetry, dynamic mechanical thermal analysis and measurements of mechanical properties and water sensitivity. The research results show that the blends exhibit a higher miscibility when PU content is lower than 15 wt% due to the hydrogen bonding interaction between urethane groups and hydroxyl groups on starch, whereas obviously phase separation occurs in the blends with more than 15 wt% PU. Incorporating PU of 4-20 wt% in TPS results in the blends with improved Young's modulus (40-75 MPa), tensile strength (3.4-5.1 MPa), elongation at break (116-176%). Further, PU also plays an important role in improving the surface- and bulk-hydrophobicity and water resistance of the resulting blends.  相似文献   

9.
The goal of this work was to develop a method for the preparative isolation of ricinoleic acid (RA) from Castor oil (CO) for use as building blocks in biopharmaceutical synthesis. The separation efficiency achieved with the impurity extraction approach (IEA) and the salting-out approach (SOA) based on utilization of monobasic alkali salt of RA was examined. SOA showed better separation efficiency. Fractional precipitation from the co-solvent system consisting of isopropyl ether:ethanol (IPE:EtOH) 65:35 v/v and applied at a CO: co-solvent system mass: volume ratio of 1:5 produced a high quality purified RA (purity 97.9–98.6%). It contains residuals of linoleic acid and oleic acid as the main impurities and satisfies all requirements of the official compendia for oleaginous vehicles for parenteral administration. The total yield of this process was 55.5 ± 2.5% and the recovery of RA was about 70% (calculated relatively to the yield of the crude product). The study of the synthesis kinetics of RA oligomers and of the biopolymer prepared from these oligomers indicated that mono-functional fatty acids (FAs) affect the composition of the oligomers' mixture and delay chain elongation of both RA oligomers and biopolymer. The developed novel process is simple, flexible, highly reproducible, inexpensive, and has high scalability potential.  相似文献   

10.
Ecofriendly autoxidation is a reaction of air oxygen with unsaturated organic molecules at room temperature. Castor oil and ricinoleic acid were ecofriendly autoxidized for 5 months to obtain castor oil macroperoxide with a Mn of 1935 g mol−1 (Pcast5m) and the ricinoleic acid macroperoxide initiator (Prici5m) with a Mn of 1169 g mol−1. Peroxide groups thermally initiated the free radical polymerization of methyl methacrylate (MMA), n-butyl methacrylate (nBMA), and styrene (S). Peroxide formation in the oxidized castor oil and ricinoleic acid was confirmed using iodometric analysis, elemental analysis, and differential scanning calorimetry technique. Peroxide decomposition in both macroperoxide initiators was observed at 166 °C for Prici5m and 170 °C for Pcast5m. Hydroxyl groups of Pcast5m were reacted with methacryloyl chloride to obtain methacrylated castor oil macroperoxide (PcastMA). The polymerization rates of the obtained macroinitiators were compared. The polymerization rate order is Pcast5m > Prici5m > PcastMA. Polymerization of styrene by PcastMA resulted in an increase in molar masses and an increase in the polymerization time while those of the styrene polymerization by Pcast5m and Prici5m remained constant. Carboxylic acid groups were reacted with amine-terminated polyethylene glycol (PEG), polydimethyl siloxane (PDMS), and polytetrahydrofuran (PTHF) while the hydroxyl functionality initiated the ring-opening polymerization of ε-caprolactone (CL). Prici-PEG-PMMA, Prici-PS-PDMS, Prici-PS-PTHF, Pcast-PS-PCL, Pcast-PCL-PMMA, and Pcast-PS-PnBMA multiblock copolymers were prepared and characterized using spectrometric, thermal, and stress–strain measurement techniques.  相似文献   

11.
Ricinoleate, a monohydroxy fatty acid, in castor oil has many industrial uses. Dihydroxy fatty acids can also be used in industry. The C18 HPLC fractions of castor oil were analyzed by electrospray ionization mass spectrometry of lithium adducts to identify the acylglycerols containing dihydroxy fatty acids and the dihydroxy fatty acids. Four diacylglycerols identified were diOH18:1-diOH18:1, diOH18:2-OH18:1, diOH18:1-OH18:1 and diOH18:0-OH18:1. Eight triacylglycerols identified were diOH18:1-diOH18:1-diOH18:1, diOH18:1-diOH18:1-diOH18:0, diOH18:2-diOH18:1-OH18:1, diOH18:1-diOH18:1-OH18:1, diOH18:1-diOH18:0-OH18:1, diOH18:2-OH18:1-OH18:1, diOH18:1-OH18:1-OH18:1 and diOH18:0-OH18:1-OH18:1. The locations of fatty acids on the glycerol backbone were not determined. The structures of these three newly identified dihydroxy fatty acids were proposed as 11,12-dihydroxy-9-octadecenoic acid, 11,12-dihydroxy-9,13-octadecadienoic acid and 11,12-dihydroxyoctadecanoic acid. These individual acylglycerols were at the levels of about 0.5% or less in castor oil and can be isolated from castor oil or overproduced in a transgenic oil seed plant for future industrial uses.  相似文献   

12.
Hydrogenated castor oil from castor oil is promisingly used as raw materials for lubricants, coatings, cosmetics, and pharmaceutics due to high melting point and stable physical properties. However, the chemical modification of the hydrogenated castor oil has been rarely investigated. Here, we report a N-phenyl-fatty-amido-1-propyl-N,N-dimethyl-amino-carboxyl-betaine surfactant derived from hydrogenated castor oil with excellent interfacial properties through a rapid synthetic process, including direct alkylation, amidation, and quaternization. The interfacial tension between crude oil and brine was ultra-low for a low dosage of 0.007 g L−1 of surfactant in aqueous solution without any alkali addition, which implies a potential application in enhanced oil recovery.  相似文献   

13.
Polyurethanes based on vegetable oil were synthesized with castor oil and toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate, using dibutyltin dilaurate as a catalyst. The effects of the nature of the diisocyanate on the evolution of the kinetics, as well as the physical and mechanical properties and the thermal stability, of the different synthesized polyurethanes were investigated, and these complement data from the literature on equivalent systems. The polymerization kinetics, degree of swelling and mechanical properties were greatly affected by the diisocyanate nature, whereas the rheological properties and thermal stability were found to be similar for all polyurethanes.

  相似文献   


14.
Biosurfactants have been used in the petroleum oil industry for oil storage tank cleaning, for reducing the viscosity of heavy oil, thereby facilitating recovery, transportation, and pipelining. Also, they are used for microbial enhanced oil recovery either from residual oil in reservoirs or from oily wastewater. The present study is an investigation of biodegradation of petroleum oil effluents using Pseudomonas aeruginosa ATCC 9027 for producing rhamnolipid biosurfactants. The processes were performed in a mechanically agitated, fully baffled, air-sparged 10 L glass fermenter with a 5 L working volume. The effect of oil concentration (1%, 1.5%, 2%, and 2.5%) on the efficiency of oil biodegradation, rhamnolipid production, surface tension, and bacterial biomass was studied. The fermentation with 1.5% oil concentration gave the highest biodegradation for aliphatic hydrocarbons (98.85%), followed by 2% oil concentration (95% degradation), then with 2.5% oil concentration (80% degradation), and finally with 1% oil concentration (66.8% degradation). Also, the complete biodegradation of polyaromatic hydrocarbons was achieved for all tested oil concentrations. On the other hand, maximum rhamnolipid production of 2.7 g L−1 as rhamnose equivalent and lower surface tension (30.2 mN m−1) were achieved at 2% oil concentration.  相似文献   

15.
蓖麻油裂解制癸二酸生产工艺研究进展   总被引:2,自引:0,他引:2  
论述了近年来蓖麻油裂解制癸二酸生产工艺的研究进展,重点介绍了生产工艺的改进、含酚废水的治理、癸二酸的提纯等方面的最新研究成果,并指出目前癸二酸生产中仍存在的问题和进一步研究的方向.特别提出了回收游离碱的新观点.  相似文献   

16.
Transesterification of palm olein with glycerol can increase the functionality by introducing additional hydroxyl groups to the triglyceride structure, an advantage compared to using palm olein directly as feedstock for producing palm‐based polyol. The objective of this study was to synthesize transesterified palm olein‐based polyol via a three‐step reaction: (1) transesterification of palm olein, (2) epoxidation and (3) epoxide ring opening. Transesterification of palm olein yielded approximately 78 % monoglyceride and has an hydroxyl value of approximately 164 mg KOH g?1. The effect of formic acid and hydrogen peroxide concentrations on the epoxidation reaction was studied. The relationships between epoxide ring‐opening reaction time and residual oxirane oxygen content and hydroxyl value were monitored. The synthesized transesterified palm olein‐based polyol has hydroxyl value between 300 and 330 mg KOH g?1 and average molecular weight between 1,000 and 1,100 Da. On the basis of the hydroxyl value and average molecular weight of the polyol, the transesterified palm olein‐based polyol is suitable for producing rigid polyurethane foam, which can be designed to exhibit desirable properties. Rigid polyurethane foams were synthesized by substituting a portion of petroleum‐based polyol with the transesterified palm olein‐based polyol. It was observed that by increasing the amount of transesterified palm olein‐based polyol, the core density and compressive strength were reduced but at the same time the insulation properties of the rigid polyurethane foam were improved.  相似文献   

17.
铜绿假单胞菌分泌鼠李糖脂能力对原油降解影响的研究   总被引:3,自引:0,他引:3  
研究了铜绿假单胞菌分泌鼠李糖脂能力对原油生物降解的作用.将保存在原油中的铜绿假单胞菌转接至甘油培养基进行继代培养,观察到各继代培养下鼠李糖脂分泌量越高则该发酵液对原油的乳化降解能力就越强,推测该菌产鼠李糖脂能力决定了该培养液对原油的乳化与降解程度.鉴于此,分别将鼠李糖脂提取液、发酵液加入到原油培养基中,观察其各自的原油乳化程度的变化趋势,发现鼠李糖脂本身可以乳化原油但不能降解原油,且其乳化能力不如去菌体的发酵液.去菌体发酵液能很快地乳化原油而同样不能降解原油.只有含菌体的发酵液既能乳化又能降解原油.因此,可以认为鼠李糖脂本身具有乳化原油的能力,但是由铜绿假单胞菌同时分泌的其它表面活性物质可能协同鼠李糖脂更好地乳化原油以促进微生物对原油的利用与降解.  相似文献   

18.
The castor plant Ricinus communis L. is the source of castor oil which has numerous uses and is a key chemical feedstock for an array of products from polymers to cosmetics. Although castor was once widely grown throughout the world, the presence of the toxic protein ricin has deterred the re‐introduction of this useful crop. In order to develop a low‐ricin or no‐ricin castor crop, a robust, accurate method for screening castor seed for ricin content is essential. In this study, we validated a sandwich enzyme‐linked immunosorbent assay for the detection of ricin and the homologous Ricinus communis agglutinin (RCA) in castor beans and screened a collection of castor lines including commercial varieties using this assay. Although the average content derived by extracting several seeds provided a fair representation of the ricin content for a given selection, there was enough seed‐to‐seed variation to justify determining the ricin/RCA content of individual seeds. Ricin levels observed ranged from 1.16 to 6.25 % by weight.  相似文献   

19.
温琰  张大庆 《广州化工》2011,39(4):65-68,96
通过间歇工艺实验和几种创新方法研究了这个裂解反应。考察了温度、时间、水分和甲酚对产物收率的影响。发现了关于水、连串反应、催化、第二反应平衡和制约癸二酸收率等方面的反应特征。确定了双温工艺条件,癸二酸收率达51.3%,2-辛醇收率达33.2%。特别指出甲酚的催化作用,为寻找新物质代替甲酚指明了方向。  相似文献   

20.
The aim of this work was the synthesis of polyester polyols from renewable sources as one of the important compounds of polymeric polyurethane (PU) adhesives. The polyester polyols were synthesized by condensation polymerization of different dicarboxylic acids with castor oil and the reaction conditions were in agreement with green chemistry principles. The preparation of PU wood adhesives was carried out by the reaction of each obtained polyester polyol with 4, 4′-diphenylmethane diisocyanate (MDI). The adhesive performance was improved by mixing the obtained polyester polyols with polypropylene glycol (PPG 400) and butanediol (BD). Different NCO/OH ratios were used to obtain adhesives with appropriate properties. The structures of the synthesized polyesters and adhesives were characterized by FTIR, thermogravimetric analysis (TGA) and lap shear strength values were also determined in various conditions such as cold water, hot water, acid and alkali solutions.  相似文献   

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