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1.
A novel polyol synthesised from castor oil by aminolysis and a partially blocked toluene–diisocyanate blocked with N,N′-diethyl lactamide was used to prepare an urethane. This was used in different weight proportions to modify epoxy amine adduct to give binders suitable for cathodic electrodeposition. The pigmented composition of these binders based on the iron oxide (natural) and titanium dioxide (rutile) gave coatings with improved performance.  相似文献   

2.
改性蓖麻油基软质聚氨酯泡沫塑料的研究   总被引:1,自引:0,他引:1  
本文研究了环氧蓖麻油配比和环氧值对蓖麻油基软质聚氨酯泡沫物理性能的影响规律,并对原料配方进行了优化,制得了适宜不同需要的改性蓖麻油基软质泡沫,使蓖麻油基软质泡沫的手感、耐老化性能明显改善。  相似文献   

3.
This paper presents the comparative studies to clarify the tribochemical reactions and disclose the tribochemical mechanisms of the polyhydroxyl group lubricants with different molecular structures and the lubrication performances of the friction pair of Nitinol alloy pin/high speed steel disc using pin-on-disc tribometer. The tribotest results show that all polyhydroxyl group lubricants can improve the lubrication performances of the friction pair and only castor oil exhibits super low friction of 0.005. It is shown that there is first the dissociation of castor oil in the presence of ester groups and then castor oil and the hydrolysis products of castor oil are easily oxidized by oxygen due to the double bonds and hydroxyl groups under the friction heating and high pressure. The sole results of the dissociations of castor oil and tribological oxidations are the provisions of the chemical reaction pathways to form the OH-terminated surfaces. Super low friction of the friction pair under castor oil lubrication can be attributed to occurring between the triboinduced degradations and oxidations, tribochemical reactions and triboformed OH-terminated surfaces resulting in the strong repulsive forces. These experimental results and analyses will support strongly and elucidate the super low friction mechanism from both scientific and application viewpoints.  相似文献   

4.
Solvent-blown rigid urethane foams prepared from a low-cost polyol mixture composed of raw castor oil and triisopropanolamine have been described. Foams with higher compressive strengths can be obtained by substituting oxidized (blown) castor oil for the raw castor oil in formulations of this type. The properties of rigid foams prepared from several commercial blown castor oils are described. The properties of these foams are correlated with the degree of oxidation of the blown oils used, as indicated by their oxygen content, density, viscosity, and refractive index. Removal of acid from blown oils having high acid values has no significant effect on the compressive strength of foams prepared from these oils. When blown castor oil is used instead of raw castor oil, less isocyanate is required to produce a urethane foam of specified density and compressive strength. Presented at the AOCS meeting in Toronto, Canada, 1962. A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.  相似文献   

5.
胡波年 《涂料工业》2004,34(8):24-26
研究了改性蓖麻油制备UV光固化涂料。由蓖麻油、环氧丙烯酸树脂UVR6100、光引发剂UVI6990制得的涂料具有优良的光泽、良好的柔韧性、良好的附着力与硬度,且当改性蓖麻油含量为40%时,漆膜性能最为优良。  相似文献   

6.
Foam stability and segmented polymeric phase morphology of polyurethane foams synthesized partially and completely from castor oil are investigated. Preliminary analysis of the impact of alterations in the polymeric phase on macroscopic stress dissipation in foams is also carried out. The stability and morphology show unique trends depending on the concentration of castor oil used in foam synthesis. While low and intermediate concentrations of castor oil does not significantly affect the foaming process; at high concentrations, the volumetrically expanding liquid matrix remains in a nonequilibrium state during the entire foaming period, resulting in significant foam decay from top. This increases the final foam cell density and decreases the plateau border thickness at bottom. In the polymeric phase of castor oil based foams, the fraction of monodentate urea increases at the cost of non‐hydrogen bonded urea. These monodentate urea domains undergo flocculation in foams synthesized completely from castor oil, thus prominently modifying the segmented morphology. The glass transition temperature of soft segments of partially substituted foams shows moderate increase, with indications of phase mixing between the polyether and castor oil generated urethane domains. Foams synthesized entirely from castor oil have significant sol fraction due to unreacted oligomers. The microscopic alterations in polymeric phase reduce the elastic recovery of partially substituted castor oil foams compared to its viscous dissipation under an applied stress. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40668.  相似文献   

7.
蓖麻油改性聚醚型水性聚氨酯乳液的性能   总被引:4,自引:0,他引:4  
以聚醚、甲苯二异氰酸酯(TDI)、一缩二乙二醇、蓖麻油为主要原料,二羟甲基丙酸(DMPA)为亲水扩链剂,三乙胺为中和剂制备了稳定的阴离子水性聚氨酯乳液(WPU),研究了NCO/OH摩尔比、DMPA及蓖麻油的加入量对WPU的耐水性、稳定性和力学性能的影响,结果表明:改性后的乳液具有较好的稳定性,适量的蓖麻油可提高胶膜的拉伸强度及耐水性。当聚醚与蓖麻油质量比为7︰3、DMPA为5%、NCO与OH摩尔比为1.3时,WPU综合性能最好。  相似文献   

8.
This paper evaluates the production of methyl esters from castor oil and methanol after neutralization of castor oil with glycerol. The reaction was carried out under atmospheric pressure and ambient temperature in a batch reactor, employing potassium hydroxide as catalyst. Results showed high yield of castor oil into methyl esters after neutralization of castor oil with glycerol. The highest yield observed was of 92.5% after 15 min of reaction. The best operating condition was obtained applying an alcohol to oil molar ratio of 6.0 and 0.5% w/w of catalyst.  相似文献   

9.
Summary  Over the past few years, the challenges of globalisation, consolidation and economical point of view have meant that manufacturers of epoxy formulations have to constantly improve their capability to meet the needs of customers. An active area for advancement is that of epoxy and polyamide resin with castor oil. Generally, people working in the coating industries are familiar with castor oil, but this paper provides information on the new use of castor oil in epoxy and polyamide resin. This novel product (castor oil-modified epoxy resin/castor oil-modified polyamide) provides a previously unattainable combination and improved flexibility and toughness to a variety of ambient cure applications. This communication will review the performance of these castor oil-modified epoxy and polyamide resin surface coatings and adhesives. Based on the results of this study, these systems offer some advantages without much affecting the traditional properties of epoxy and polyamide resin in a variety of applications.  相似文献   

10.
蓖麻油是具有独特性能的植物油类,分子中含有羟基、酯基、烯键等官能团,这些官能团可以单独进行反应得到蓖麻油衍生物,也可以其中两个或三个基团组合先后进行不同反应得到特殊用途的蓖麻油衍生物。主要对三种官能团单独进行化学反应综述归类,系统地介绍蓖麻油中各官能团所能发生的反应,简述不同反应产物的用途,较全面地介绍了蓖麻油基础化学反应知识,便于新反应和多官能团反应的设计和新产品的开发,提高蓖麻油深加工技术水平。  相似文献   

11.
Thin-Layer Chromatographic Separation of Partial Glycerides of Castor Oil Fatty Acids Partial glycerides of castor oil fatty acids and hydrogenated castor oil fatty acids were prepared by esterification or glycerolysis and fractionated, together with commercial products, by TLC (especially by two-dimensional technique) on silicagel 60 precoated plates. By comparison of the two-dimensional chromatograms of the partial esters of castor oil fatty acids with synthetic standards, such as partial glycerides of ricinoleic, di- and tri-ricinoleic acids, estolides of castor oil fatty acids esterified to partial glycerides, and partial esters of castor oil fatty acids with 1,3-propanediol, the substances that could be identified were partial glycerides of ricinoleic, diricinoleic and triricinoleic and tetraricinoleic acids as well as partial glycerides, which contained, in addition to ricinoleic, diricinoleic and triricinoleic acids, fatty acids without hydroxyl groups as terminal estolide chain. The TLC enables an insight into the complex character of the glyceride composition of partial glycerides of castor oil fatty acids.  相似文献   

12.
Summary The preparation and properties of two series of castor oil urethane foams, one from castor oil and the other from elaidinized castor oil, were investigated. The first series of foams was made from prepolymers containing 60% of castor oil prepared at increasing temperature levels to vary the degree of crosslinking in the final foams. These foams had lower tensile strengths than observed for a previously prepared foam of 60% castor oil and did not show significant differences in water resistance as crosslinking varied. They were increased nearly 100% in compressive strength with increased crosslinking and had very good shrinkage characteristics as values of only 1 to 2% were obtained. A second series of foams was prepared from 50, 60, 70, and 80% of elaidinized castor oil to compare with foams from a similar series from castor oil. This series of foams of 50 to 80% elaidinized castor oil contents was similar in density (1.7 to 6.7 lbs./cu. ft.), had improved shrinkage characteristics (11, 1, 3, and 4%, respectively), showed increased compressive and tensile strengths (up to 12.1 p.s.i. at 50% compression modulus and 34.7 p.s.i. ultimate tensile for the 60% foam formulation), and had better water-resistance properties (411 to 155%vs. 515 to 170% water absorption) than the analogous foams from castor oil. In general, humid aging only slightly affected the values obtained for the foams and was significant in only a few instances,e.g., decreased tensile in the elaidinized castor oil series. Thus increasing crosslinks in the foam apparently did not improve water resistance but did improve shrinkage characteristics in addition to some increased strength properties, as would be anticipated. Foams from elaidinized castor oil, while similar in density and foaming characteristics to analogous foams from castor oil, exhibited less shrinkage and improved water-resistance. Presented at the 50th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., April 20–22, 1959. Ono of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   

13.
有机硅改性磷酸化蓖麻油的合成   总被引:1,自引:1,他引:0  
以蓖麻油为主要原料,经醇解反应、与有机硅接枝、磷酸化反应合成了加脂剂含硅磷酸化酯交换蓖麻油。通过红外光谱、凝胶渗透色谱等确定了合成产物的结构、组成和相对分子质量,并对各步反应条件进行了优化实验:当蓖麻油与丁醇的摩尔比为1(∶3-4)时,蓖麻油的酯交换深度比较理想;反应温度在80-90℃时,接枝率可达85%以上;在较低的温度下,蓖麻油接枝产物可以发生磷酸化反应,生成的磷酸化蓖麻油平均相对分子质量为1 200左右,乳液稳定。  相似文献   

14.
蓖麻油及其衍生物在涂料中的应用   总被引:8,自引:0,他引:8  
蓖麻油作为一种可再生资源,具有较高工业经济价值。本结合蓖麻油的组成结构与性质,概述了蓖麻油和脱水蓖麻油、氧化蓖麻油等相关衍生物在涂料中的应用现状及其应用前景。  相似文献   

15.
以可再生的蓖麻油为主要原料,首次采用甲醇钠和三乙醇胺为混合催化剂,与甘油在N2环境中发生酯交换反应,生成蓖麻油单甘脂和蓖麻油甘二酯。考察了催化剂用量、甘油用量、反应温度、反应时间对蓖麻油单甘脂转化率、蓖麻油甘二酯转化率和总转化率的影响,并与传统的催化剂甲醇钠、钛酸四丁酯催化酯交换反应进行了比较。采用FT-IR、GPC对产物的结构、相对分子质量和转化率进行了表征。通过单一变量控制法对反应的条件进行优化。结果表明,催化剂用量为蓖麻油质量的0.75%、蓖麻油和甘油的质量比为50:12.33、反应温度为180℃、反应时间为2.5h时,蓖麻油多元醇的转化率最高,可达92.54%,与传统催化剂相比较,混合催化剂不仅提高了产物的转化率和羟值,而且使产品的色泽降低。  相似文献   

16.
In this study a novel macromer technique has been described for the styrenation of triglyceride oils. Macromers were prepared through the interesterification of castor oil with linseed oil followed by esterification with acrylic acid. In this preparation various castor oil/linseed oil ratios were applied to obtain a macromer which gave a copolymer with good film properties after copolymerization with styrene. Macromers were styrenated at 100°C using benzoyl peroxide as an initiator. The styrenation leads to improved film properties with the related interesterification product although castor oil is a non‐drying oil.  相似文献   

17.
Summary A systematic investigation of some 21 castor polyols as base materials for preparing urethane foams was carried out. Prepolymers were prepared both from individual castor polyols and from mixtures of them with an anhydrous castor oil. Foams formed from these prepolymers were checked for shrinkage on cure, density, and modulus. From the wide range of results obtained it is evident that castor polyols can serve as effective urethane components. Aside from serving as major polyols for reaction with di-isocyanates, they can also be used as modifying polyols a) to speed up prepolymer preparation, b) to adjust prepolymer viscosity to any required degree, c) to minimize loss of modulus on humid aging, and as cross-linking centers with negligible loss of foam modulus. Details covering the preparation of a nonshrinking, semi-rigid, light-weight urethane foam based on an 85% anhydrous castor oil/15% epoxidized castor oil mix are outlined in the article. Presented at the Spring Meeting, American Oil Chemists' Society, Memphis, Tenn., April 20–23, 1958.  相似文献   

18.
蓖麻油基下游产物及蓖麻油增塑剂的研究及其应用进展   总被引:1,自引:0,他引:1  
随着全球化石资源消耗量的不断剧增, 能源危机问题引起了广泛的关注。在植物资源能源化的利用中, 以蓖麻油为原料开发高附加值下游产品已成为研究热点。本文介绍了国内外蓖麻油基下游产品的制备方法、产品性能及应用领域等方面。回顾了脱水蓖麻油、酯交换蓖麻油、环氧化蓖麻油、蓖麻油基聚氨酯等下游产物的制备与应用性能研究。简述了蓖麻油基增塑剂的种类及应用领域, 具体分析了环氧乙酰蓖麻油酸甲酯的制备方法及产品特性。提出了在我国蓖麻油基增塑剂的生产过程中反应温度、催化剂用量等因素影响环氧基团稳定性的问题, 指出目前我国催化合成蓖麻油基增塑剂的趋势和发展方向。  相似文献   

19.
The chemistry of castor oil and its derivatives is reviewed with particular reference to work done in India in general and at the Regional Research Laboratory in Hyderabad in particular. Topics covered are the structure of castor oil, preparation of ricinoleic acid and its glycerides, monoglycerides, surfactants from castor oil, diverse hydrogenations, dehydration, preparation and properties of estolides, alkali fusion or oxidation to dibasic acids, hydroxylation and acetoxy-epoxies, urethanes and polymerisable monomers. Presented at the Plenary Session of the ISF-AOCS World Congress, Chicago, September 1970.  相似文献   

20.
蓖麻油基聚酯多元醇的制备及表征   总被引:1,自引:0,他引:1  
以可再生资源蓖麻油、苯酐和小分子醇为原料,钛酸正丁酯为催化剂,经酯化、缩聚合成蓖麻油基聚酯多元醇,考察了反应时间对聚酯多元醇酸值的影响以及不同官能度的小分子醇对醇解蓖麻油结构和羟值的影响。采用红外光谱仪(FT—IR)、凝胶色谱(GPC)、热失重仪(TGA)对醇解蓖麻油、蓖麻油基聚酯多元醇的相对分子质量、热稳定性进行了表征。结果表明,随着小分子醇官能度的增加,醇解体系中单酯和二酯含量明显减少,转化率也相应减小;甘油醇解蓖麻油和蓖麻油基聚酯多元醇较普通聚醚多元醇635具有更高的热稳定性。  相似文献   

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