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Zahariah Ismail Rathidevi Nadarajan Anuar Kassim Mohd. Zaizi Desa 《Journal of Dispersion Science and Technology》2013,34(2):261-265
Dihydroxystearic acid (DHSA) and octyl dihydroxystearate (DHSA‐octyl ester) have been successfully prepared from palm oleic acid. Preliminary results showed that these compounds are suitable in personal care and cosmetics products. The objective is to study the phase behaviors in ternary system of DHSA/DHSA‐octyl ester/RBD palm kernel olein (RBDPKOo) and medium chain triglycerides (MCT) at 85°C. The phase changes were observed through polarizing light while the formation of texture was confirmed using polarizing microscope combination with heating. From the ternary phase diagram, results showed that all ratios of DHSA/DHSA‐octyl ester were completely in two‐phase region with various concentrations of RBDPKOo/MCT. Needles and spherulite textures were found in this system. The viscosity and thixotropy of these mixtures were also determined using rheometer. DHSA and DHSA‐octyl ester has a melting point of 84.4°C and 64.3°C, respectively. 相似文献
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有机二羧酸是重要的聚酯单体,广泛应用于化学纤维、轻工、电子等工业生产的各个方面.随着社会工业化的发展,以大量不可再生的石油资源为原料生产有机酸造成地球石油资源的匮乏和环境污染问题.通过生物质及其衍生物来制备高附加值化学品有机二羧酸,引起了化工应用领域的广泛关注.在合成生物质有机二羧酸的研究中,设计与制备具有高活性、高稳定性的催化剂具有重要意义.近年来,许多工作对催化剂的种类进行了探索,并取得了一定的研究进展.本文重点从生物质原料、催化剂性能评估、反应机理等方面对制备C3~C6二羧酸的催化体系进行了综述,包括丙二酸、丁二酸、2,5-呋喃二甲酸和己二酸,并对生物质有机二羧酸制备领域的发展进行了展望. 相似文献
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在无溶剂条件下制备环氧蓖麻油,对参加环氧化反应的有机酸和催化剂进行选择,研究了反应时间和反应温度对产物环氧值的影响。通过正交实验对环氧化合成条件进行优化,结果表明,蓖麻油/乙酸/双氧水/磷酸(质量比)=1:0.15:0.8:0.01,反应温度50℃,反应时间3h,所得产品环氧值达6.95%,采用FT-IR和1HNMR方法对产品进行了表征。整个过程操作简单,反应时间短,反应条件温和。 相似文献
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Ibrahim O. Mohamed 《Applied biochemistry and biotechnology》2012,168(6):1405-1415
Cocoa butter equivalent was prepared by enzymatic acidolysis reaction of substrate consisting of refined palm olein oil and palmitic?Cstearic fatty acid mixture. The reactions were performed in a batch reactor at a temperature of 60?°C in an orbital shaker operated at 160?RPM. Different mass ratios of substrates were explored and the compositions of the five major triacylglycerol (TAG) of the structured lipids were identified and quantified using cocoa butter-certified reference material IRMM-801. The reaction resulted in production of cococa butter equivent with TAG compostion (POP 26.6 %, POS 42.1, POO 7.5, SOS 18.0 %, and SOO 5.8 %) and melting temperature between 34.7 and 39.6?°C which is close to that of the cocoa butter. The result of this research demonstrated the potential use of saturated fatty acid distillate (palmitic and stearic fatty acids) obtained from palm oil physical refining process into a value-added product. 相似文献
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Charlotte Menager Nathanaël Guigo Luc Vincent Nicolas Sbirrazzuoli 《Journal of polymer science. Part A, Polymer chemistry》2020,58(12):1717-1727
The curing of epoxidized linseed oil (ELO) with three different bio-based dicarboxylic acids (sebacic acid, suberic acid, and succinic acid) has been investigated. No accelerators or catalysts were used and the resulting thermosets are 100% bio-based. Structural investigations of the three crosslinked ELO resins were made using FTIR spectroscopy and TMA, that is, tensile tests, TGA, and DMA. As evidenced by FTIR measurements ELO and dicarboxylic acids reacts but no major differences can be distinguished between the dicarboxylic acids. Non-isothermal curing has been conducted by rheological and DSC measurements. Advanced isoconversional analysis applied to DSC data in association with the complex viscosity variations gives new insights into the polymerization mechanism. The length of dicarboxylic acid carbon chain modifies the reaction rate. Then, a correlation between reaction rate, activation energy, pre-exponential factors, polymerization mechanism, and change in rate-limiting step was shown. DMA and tensile tests highlight the relationship between the carbon chain length, reactivity, and thermomechanical properties. The use of succinic acid allows reaching a higher Tg and thermal stability. 相似文献
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用FTIR研究环氧化天然橡胶的热老化 总被引:8,自引:0,他引:8
与天然橡胶(NR)相比,环氧化天然橡胶(ENR)具有良好的耐油性和气密性[1,2],并由于环氧基团而有一定的极性,同其它高聚物的相容性较好.通过环氧基团的二次反应,ENR分子链可接上其它的功能团,满足一些特殊的用途[3,4].对于ENR的力学性能、共... 相似文献
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M. Sc. Philipp Roesle M. Sc. Florian Stempfle B. Sc. Sandra K. Hess B. Sc. Julia Zimmerer Dr. Carolina Río Bártulos Dr. Bernard Lepetit Angelika Eckert Prof. Dr. Peter G. Kroth Prof. Dr. Stefan Mecking 《Angewandte Chemie (International ed. in English)》2014,53(26):6800-6804
Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2‐(tBu2PCH2)2C6H4}Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17‐ and 1,19‐diesters in high purity (>99 %). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester‐17/19.17/19 with an advantageously high melting and crystallization temperature. 相似文献
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原位聚合法制备PANI/PET导电织物及其性能分析 总被引:1,自引:0,他引:1
在聚酯纤维基材及其织物表面,原位聚合形成厚度约1~2μm聚苯胺包覆层,制得聚苯胺(PANI)/聚酯(PET)导电织物.PANI层优异的导电性能使之成为有广阔发展前景的柔性电磁屏蔽材料.正交试验分析研究了苯胺单体浓度、氧化剂:苯胺摩尔比、掺杂酸浓度、反应时间对PANI包覆层外观形态、与基体结合牢度以及导电性的影响.实验表明:在经适当前处理的PET基材表面,以苯胺单体浓度为0.25mol/L、氧化剂与苯胺摩尔比为1∶1、掺杂酸浓度0.5 mol/L、反应时间60 min、反应温度为0~20℃时制备的PANI/PET导电织物方阻最小,导电性最好;掺杂酸酸性越强,导电性越好.SEM、FTIR及XRD测试表明涤纶织物表面有均匀连续的聚苯胺膜存在.分析表明聚苯胺分子链中氧化结构与还原结构含量基本相等,说明聚苯胺渗入纤维内部,使纤维无定形区面积增加,结晶度减小. 相似文献
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Nagarjuna Reddy Paluvai Smita Mohanty S. K. Nayak 《International Journal of Polymer Analysis and Characterization》2015,20(4):298-306
Renewable resource-based epoxidized castor oil (ECO) was synthesized and used as a prime material to develop acrylated epoxidized castor oil (AECO) networks. AECO nanocomposites were prepared by the sol-gel method from organo-modified montmorillonite (OMMT) clay and silane. It was found that the AECO/1 wt.% OMMT system increased in tensile strength from 28 to 37 MPa and flexural strength from 54 to 63 MPa as compared with the AECO system. The non-isothermal cure kinetics of the bio-based systems was studied using differential scanning calorimetry. The activation energy of the AECO/OMMT system obtained from Kissinger and Flynn-Wall-Ozawa models is lower than that of AECO system. 相似文献
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Finishing of Polyester Fabrics with Cyclodextrins and Polycarboxylic Acids as Crosslinking Agents 总被引:3,自引:0,他引:3
B. Martel M. Morcellet D. Ruffin L. Ducoroy M. Weltrowski 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):443-446
CDs were grafted onto PET fibers by the intermediate of polycarboxylic acids thatplayed the role of crosslinking agents. We evidenced that grafting occurred despitethat no reaction could happen between the polycarboxylic acids and PET. It wasconcluded that the mode of grafting occurred through the formation of a crosslinkedcopolymer between PCA and CDs. This copolymer was not covalently fixed to thefibers, but physically adhered or was entangled into the fibrous network so that grafting was resistant to washings and was permanent. We report that the grafting rate depended on (i) temperature of curing; (ii) time of curing; (iii) the ratio PCA/CD. In the most drastic conditions, the weight increase of the fabrics due to the graft reaction could reach 25–30%-wt. , , -CDs and HP--CD successfully reacted but not RAMEB because of its reduced number of free hydroxyl groups available for the esterification reaction. 相似文献
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Jihyun Hwang Heeju Jun Seoye Roh Seong Jae Lee Jeong Min Mun Seung Wook Kim Min-Yu Chung In-Hwan Kim Byung Hee Kim 《Molecules (Basel, Switzerland)》2021,26(11)
Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter. 相似文献
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Mitsuhiro Yamashita Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1993,31(6):1513-1518
A new triphenylphosphine-type monomer, bis(4-aminophenyl) phenylphosphine, was synthesized starting from p-bromoaniline and dichlorophenylphosphine. The aromatic polyamides (aramids) containing triphenyphosphine unit in the polymer backbone was prepared by the polycondensation of this diamine with various aromatic diacid chlorides using a low-temperature solution method in N,N-dimethylacetamide (DMAc). The aramids having inherent viscosities of 0.4–0.7 dL/g were obtained in quantitative yields. The polymers were amorphous and soluble in various organic solvents such as DMAc, N-methylpyrrolidone, dimethyl sulfoxide, pyridine, and m-cresol. Transparent, tough, and flexible films were obtained by casting from the DMAc solutions. The glass transition temperatures of the aramids were in the range of 265–310°C, and the 10% weight loss temperatures were above 400°C in air. © 1993 John Wiley & Sons, Inc. 相似文献