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81.
以十二醇、二苯醚和发烟硫酸为原料合成了十二烷基二苯醚磺酸盐.考察了物料摩尔比和反应温度对十二烷基二苯醚磺酸盐组成的影响,并采用高效液相色谱/质谱对磺化产物进行了分析表征.结果表明:十二烷基二苯醚进料量的增加有利于单磺酸盐的生成;温度低于50℃时,温度的升高有利于双磺酸盐的生成;而温度大于50℃时,温度的升高有利于单磺酸...  相似文献   
82.
王卫  阎露海 《石化技术》2011,18(1):22-26
介绍了两种用于控制1,3(1,4)-双(叔丁基过氧异丙基)苯缩合反应速率的分析方法(化学滴定方法和高效液相色谱法).针对高效液相色谱测定方法,详细介绍了液相色谱法测定条件的确定、回收率实验、精密度实验等,并优化了液相色谱法的分离条件.相比化学滴定法,高效液相色谱法是一种确保生产安全、提高产品质量的更加适宜的分析方法.  相似文献   
83.
曲华 《无机盐工业》2011,43(12):32-35
以γ-氧化铝(γ-Al2O3)为载体,采用均匀沉淀法制备了不同氧化锌(ZnO)负载量的纳米ZnO/γ-Al2O3复合物。通过X射线衍射(XRD)、扫描电镜(SEM)、红外光谱(FT-IR)和氮气吸附,对复合物的结构、表面形貌、组成和比表面积进行了表征。以壬基酚聚氧乙烯醚(NPE-10)和苯酚为模型污染物,对复合物的光催化性能进行了评价。结果表明:当ZnO与γ-Al2O3按质量比为2∶1加料制备ZnO/γ-Al2O3复合物时,ZnO成功负载到γ-Al2O3表面,并形成均匀的薄膜;以制备的ZnO/γ-Al2O3复合物为催化剂在紫外光照射2 h后NPE-10的降解率达到93%,苯酚的降解率达到20%,且它们的降解率均随着溶液初始浓度的增大而降低。  相似文献   
84.
硬脂酸单乙醇酰胺聚氧乙烯醚的合成及性能研究   总被引:1,自引:0,他引:1  
以硬脂酸为基本原料,与单乙醇胺反应后得到硬脂酸单乙醇酰胺,再与环氧乙烷(EO)在碱性催化剂作用下进行乙氧基化反应,合成具有不同聚合度的聚氧乙烯醚非离子表面活性剂。通过红外光谱图和NMR表征,确定了产品的结构和平均聚合度,并测试了产品的表面张力、cmc值、γcmc、HLB值和浊点等表面活性。  相似文献   
85.
以双酚A和溴丙炔为原料,采用相转移催化合成法合成了二丙炔基双酚A醚,利用红外和核磁对其结构进行了表征。采用示差扫描量热法(DSC)对二丙炔基双酚A醚的固化反应历程进行了研究。分别由Kisserger方程和Ozawa方程求得二丙炔基双酚A醚聚合反应的活化能分别为127.3KJ/mol和131.6KJ/mol。用Crane经验方程求得固化反应的反应级数接近于1。研究表明,二丙炔基双酚A醚具有较低的固化反应活化能以及较宽的加工窗口,这有利于二丙炔基双酚A醚树脂的加工成型。  相似文献   
86.
对异丙醇装置副产二异丙醚的分离提纯工艺进行模拟与优化,以水作为萃取剂,基于NRTL模型,使用Aspenplus化工模拟软件的Extract和Radfrac模块进行萃取和精馏模拟,并利用灵敏度分析工具对精馏塔工艺参数进行优化。结果表明,以水做萃取剂再经过精馏工艺提纯二异丙醚是可行的。优化得到最佳工艺参数为精馏塔为30块塔板,原料进料位置在第11块。质量回流比为1.5,精馏塔底二异丙醚纯度可达99.99%,模拟和优化结果对工业化设计和生产具有重要的指导意义。  相似文献   
87.
Dimethyl ether (DME) has been considered as a substitute for diesel fuel because it has a low auto-ignition temperature and produces less NOx, SOx, and particulate matter. However, the introduction of DME vehicles needs widely available DME supply stations. Moreover, the preparation of safety regulations for DME supply stations is very important, and so safety data is needed. Therefore, the present paper reports the hazards of the DME jet diffusion flame, which is one of several hazardous properties of DME, by studying the results of leaking gas and liquid DME. DME jets were released horizontally from circular nozzles whose diameters were 0.2, 0.4, 0.8 and 2 mm, and the release pressure was varied from the saturated vapor pressure to 2 MPa. When gaseous DME was released at the saturated vapor pressure, the flame was blown out. However, when liquefied DME was released, the flame formed. We obtained the experimental equations for estimating the scale and thermal hazards of DME diffusion flames.  相似文献   
88.
A series of poly(arylene ether)s ( 7a–7f ) were successfully synthesized by aromatic nucleophilic substitution reactions of imidoaryl biphenol (5), 4,9‐bis‐(4‐hydroxy‐phenyl)‐2‐phenyl‐benzo[f]isoindole‐1,3‐dione with six different trifluoromethyl substituted bisfluoro monomers ( 6a–6f ). The weight‐average molar masses of the polymers were up to 280 kD as measured by GPC. These poly(arylene ether)s exhibited glass transition temperatures up to 361°C in DSC. These polymers showed very high thermal stability up to 558°C for 10% weight loss under synthetic air in TGA. Except 7d–7f, remaining polymers 7a–7c were soluble in a wide range of organic solvents. Transparent thin films of these polymers cast from DCM or NMP exhibited tensile strengths up to 75 MPa and elongation at break up to 41% depending on their exact repeating unit structures. These poly(arylene ether)s showed cut‐off wavelength in between 400 and 450 nm except 7d and water absorption were in the range of 0.4 to 0.6%. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
89.
Emulsion copolymerization of ω‐chlorotetrafluoroethyltrifluorovinyl ether (Cl(CF2)2OCF = CF2 (FVE)) with tetrafluoroethylene (CF2 = CF2 (TFE)) was investigated at various monomer ratios. The copolymerization rate is below the rate of TFE homopolymerization and the copolymerization kinetics depends on the FVE content in the reaction medium. The copolymer composition is very similar if the FVE content in monomer mixture is ≤2.5 mol %. However, the percent amount of FVE in the copolymer, the copolymerization rate, and molecular mass of synthesized copolymers decrease noticeably with increase in the FVE content in the monomer mixture. The constants of copolymerization are r1= 2.8 (TFE) and r2 = 0.03 (FVE). The copolymer is a statistical polymer consisting of TFE blocks and individual FVE molecules between the blocks. The average molecular mass of copolymers is significantly less than that of the TFE homopolymer (PTFE) synthesized at the same conditions. The morphologies of PTFE and copolymer powders were investigated by thermomechanical analysis and are not similar. The copolymer has a completely amorphous diblock morphology depending on the FVE content. The introduction of FVE molecules into the copolymer macromolecules is accompanied by reduction of the crystalline portion of copolymer. If the FVE content in copolymer is ≥3.5 mol %, the copolymer macromolecules completely lose the ability to form crystalline portions as a result of their amorphicity. The introduction of up to 2.4 mol % FVE into the copolymer macromolecules yields a highly thermostable and meltable copolymer which can be processed by using the industrial processes used widely for thermoplastics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
90.
Poly(ether ether ketone)s and poly(ether ether ketone ketone)s containing pendant pentadecyl chains were synthesized by polycondensation of each of the two bisphenol monomers viz, 1,1,1‐[bis(4‐hydroxyphenyl)‐4′‐pentadecylphenyl]ethane and 1,1‐bis(4‐hydroxyphenyl)‐3‐pentadecyl cyclohexane with activated aromatic dihalides namely, 4,4′‐difluorobenzophenone, and 1,3‐bis(4‐fluorobenzoyl)benzene in a solvent mixture of N,N‐dimethylacetamide and toluene, in the presence of anhydrous potassium carbonate. Polymers were isolated as white fibrous materials with inherent viscosities and number average molecular weights in the range 0.70–1.27 dL g?1 and 76,620–1,36,720, respectively. Poly(ether ether ketone)s and poly(ether ether ketone ketone)s were found to be soluble at room temperature in organic solvents such as chloroform, dichloromethane, tetrahydrofuran, and pyridine and could be cast into tough, transparent, and flexible films from their solutions in chloroform. Wide angle X‐ray diffraction patterns exhibited a broad halo at around 2θ = ~ 19° indicating that the polymers containing pentadecyl chains were amorphous in nature. In the small‐angle region, diffuse reflections of a typically layered structures resulting from the packing of pentadecyl side chains were observed. The temperature at 10% weight loss, obtained from TG curves, for poly(ether ether ketone)s and poly(ether ether ketone ketone)s were in the range 416–459°C, indicating their good thermal stability. A substantial drop in glass transition temperatures (68–78°C) was observed for poly(ether ether ketone)s and poly(ether ether ketone ketone)s due to “internal plasticization” effect of flexible pendant pentadecyl chains. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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