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1.
丙烯酸高级醇酯的合成   总被引:1,自引:0,他引:1  
丙烯酸高级醇酯是制备多种涂料、助剂与粘合剂的重要原料,酯交换反应是目前合成这类酯的主要途径。为了改进现有方法,我们以甲醇镁Mg(OMe),为催化剂,2,2,6,6-四甲基-4-羟基哌啶氮氧自由基(TMHPO)为阻聚剂,利用酯交换反应合成丙烯酸C_8—C_(16)正构偶数碳醇酮,获得了良好结果。本法具有操作简便、催化剂活性高、阻聚剂用量少、反应时间短、丙烯酸高级醇酯产率高等特点。  相似文献   

2.
报道了一种纳米金催化(杂环)芳基酯与卤代烷经由C—O键活化的酯交换反应.在一系列负载金纳米颗粒和钯纳米颗粒催化剂中,粒径为3.63nm,负载量为3wt%的Au/γ-Al_2O_3催化剂表现出最佳催化活性.该催化剂重复使用五次后仍表现出较高活性.对反应前后催化剂的X射线光电子能谱(XPS)分析表明,该反应可能是通过以Au~0为始态的催化循环来进行的.  相似文献   

3.
不同类型的五价膦(磷)酸酯在催化量的卤化钠存在下能顺利地与卤代烷反应,实现温和条件下的酯烷基交换.无机盐的性质、卤代烷的结构以及膦(磷)酸酯的类型对反应均有影响.以此法制备烷基膦酸混合酯具有原料易得、操作简单的特点,但得率尚待进一步提高.对反应的机理也作了讨论.  相似文献   

4.
KF-Al2O3催化丙烯酸-β-羟乙酯合成高大彬伍伟夫(大连大学化学化工系大连116622)关键词丙烯酸-β-羟乙酯KF-Al2O3催化中图分类号O623.612丙烯酸-β-羟乙酯(HEA)是一种用途广泛的有机单体,可用于纤维加工、涂料、粘接剂、橡胶...  相似文献   

5.
丙烯酰化β-环糊精单体的合成与表征   总被引:2,自引:0,他引:2  
环糊精高分子在生物医用材料等领域中不断得到广泛的研究和应用[1-4]。环糊精单体是合成环糊高分子的重要中间体,丙烯酸β-环糊精酯的合成虽然早在1976年就由Harada A[5]采用丙烯酸间硝基苯酯与环糊精在碱性水溶液中进行酯交换法得到,主要为单取代产物。但该法反应所得产物不易  相似文献   

6.
噻唑烷类手性配体在催化不对称硅氢化反应中的应用   总被引:3,自引:0,他引:3  
合成了7种手性噻唑烷配体络铑(Ⅰ)络合物催化剂并考察了它们对苯乙酮不对称硅氢化反应的催化性能.研究发现由L-半胱氨酸或其酯制备的取代噻唑烷类手性配体新生成的C_2手性中心的构型对催化不称硅氢化反应的最终结果几乎没有影响,并且首次以定量的结果报道了造成了这一现象的直接原因:在铑(Ⅰ)络合物[Rh(COD)Cl])2催化作用下手性噻唑烷配体的C_2手性中心发生了快速外消旋化反应.  相似文献   

7.
甲基丙二酸乙酯等烷基取代的丙二酸酯类是有机合成常用原料。实验室通常采用卤代烷和丙二酸酯反应制备,但往往含有同系物杂质。这些同系物用一般蒸馏或分馏方法很难分离干净,但可用气相色谱法顺利地进行分离和分析。  相似文献   

8.
2-位取代的环戊-2-烯酮是一类重要的有机合成中间体,它们的合成方法虽然已有不少文献报道,但大都路线较长,原料难得,条件苛刻且收率较低.本文报道一个以环戊二烯为原料,仅两步反应合成2-烷基环戊-2-烯酮的简便新方法. 以聚乙二醇(PEG)作为相转移催化剂,环戊二烯在氢氧化钾作用下与卤代烷在固-液相条件下反应,可方便地得到相应的烷基取代环戊二烯,主要为1-位和2-位烷基取代异构体的混合物.通过该方法制备烷基环戊二烯较之采用钠氨于液氨中反应的通常制备方法更可取.烷基环戊二烯进一步于甲醇中经溴代及酸性水解后,即可得到2-烷基环  相似文献   

9.
氯代甲酸(2-乙基)己酯是一种化工中间体,主要用来制备过氧化二碳酸二(2-乙基)己酯(简称EHP),EHP是一种高活性聚合引发剂。由固体光气和2-乙基己醇为原料合成氯代甲酸(2-乙基)己酯的研究未见报道。本文以固体光气和2-乙基己醇为原料合成了氯代甲酸(2-乙基)己酯,研究了反应物加入顺序、反应时间、反应温度、催化剂种类及用量对氯代甲酸(2-乙基)己酯收率和纯度的影响,得到了优化的合成工艺,对产物结构进行了分析,进一步用其合成了常用的高活性聚合引发剂过氧化二碳酸二(2-乙基)己酯(EHP)。  相似文献   

10.
α,ω-二(1-H-苯并三唑基)烷烃的合成和生物活性的研究   总被引:1,自引:0,他引:1  
在相转移催化剂存在下,以苯并三唑为原料与二卤代烷反应合成了4个新的α,ω-二(1-H-苯并三唑基)烷烃,它们的结构经元素分析,IR和1H NMR证实.初步考查了它们的生物活性.  相似文献   

11.
丙烯酸2,2,3,3-四氟丙酯的合成   总被引:4,自引:1,他引:3  
含氟丙烯酸树脂的性能明显优于普通丙烯酸类树脂,其表面能、折光率、摩擦系数均低,耐候、不粘、疏水、疏油、防尘、化学性质稳定,已用作纤维处理剂、皮革助剂、光纤涂覆剂、光纤材料、耐候涂料、齿科材料等。合成含氟丙烯酸树脂的单体,目前国内依赖进口,合成步骤多、反应周期长,使用的有机酸原料几乎都为甲基丙烯酸。本文使用丙烯酸和四氟丙醇(简称为N1醇)为原料,合成丙烯酸2,2,3,3-四氟丙酯(TFPA),考察了阻聚剂类型、原料配比、硫酸的添加量、反应时间等对产物收率的影响。  相似文献   

12.
A new aromatic based monomer 2-phenoxy-2-phenylethyl acrylate (PPEA) was synthesized. Copolymers of PPEA with 2-phenylethyl acrylate (PEA) were prepared by free radical polymerization. The reactivity ratios were estimated using various graphical methods. Structural parameters of the copolymers were obtained by calculating the dyad monomer sequence fractions and the mean sequence length. Optical properties of polymers such as refractive indices and UV-Visible absorption were investigated. The glass transition temperature and thermal degradation behavior of the copolymers were studied. Combined with the RI, transparency and thermal properties, prepared copolymers hold great promise as materials for intraocular lens applications.  相似文献   

13.
A new kind of ultraviolet (UV) curable waterborne polyurethane acrylate dispersion was synthesized based on hydroxyl-terminated polybutadiene (HTPB), poly-(propylene glycol) (PPG), isophorene diisocyanate (IPDI), 2-hydroxy ethyl acrylate (HEA) and dimethylol propionic acid (DMPA) after neutralizing by triethylamine (TEA). 2-Hydroxy-1-[4-2-hydroxyethoxy) phenyl]-2-methyl-1-propanone (Irgacure 2959) was used as a photoinitiator and deionized water as a diluent. Fourier transform infrared (FTIR) analysis was used to identify the chain structure of the UV-curable polyurethane prepolymer based on HTPB and the curing process. Effects of relative content of HTPB and PPG on emulsion stability, resistance to water and ethanol, thermal stability, compatibility of soft and hard segment, as well as the mechanical property of the cured film were investigated. Translated from Polymer Materials Science and Engineering, 2006, 22(3): 199–203 (in Chinese)  相似文献   

14.
Thermo- and photo-responsive emulsions were prepared using mineral oil as an oil phase and a thermo- and-photo-sensitive polymer as an emulsifier. Hydroxyethyl acrylate (HEA) was copolymerized with Coumaryl acrylate (CA) and 2-Ethylhexyl acrylate (EHA) by a free radical reaction with the content of CA in the reaction mixture being varied (0, 0.5, 1, 2, 3 mol%) and the content of EHA being kept constant (2 mol%). CA was used as a photo-responsive comonomer and EHA was used as a hydrophobic comonomer to endow the copolymer with amphiphilicity. The copolymers prepared using the HEA/CA/EHA mixture where CA content was 1, 2, 3 mol% exhibited a phase transition in the range of 20°C– 45°C, and the phase transition temperature decreased with increasing the content. The CA of the copolymers was readily dimerized under the irradiation of UV (365 nm. 400 W) and the dimerization degree was 27%–47% in 60 min. The droplet size of emulsions significantly increased with increasing the temperature from 27°C- 50°C, possibly due to the thermal contraction of the copolymers. Also, the size markedly increased by 60 min-irradiation of the UV light, possibly because of the photo collapse of the copolymers.  相似文献   

15.
杂多酸催化合成丙烯酸-2-乙基己酯   总被引:2,自引:0,他引:2  
杂多酸(盐)作为性能优良的酸性、氧化性或二者兼具的双功能催化剂应用在许多有机合成反应中[1],其中有些反应已成功实现了工业化[2],因此近年来有关杂多酸(盐)催化反应的应用研究倍受关注.丙烯酸2乙基己酯(简称HA)是重要的高分子单体,与其它单体进...  相似文献   

16.
我们曾报道过含吗啉基丙烯酰类单体在过氧化物或芳酮存在下的热聚合及光聚合,以及做为氧化-还原引发体系组分引发烯类单体聚合的研究。利用这类单体与过硫酸盐所构成的引发体系可以获得分子量达千万的聚丙烯酰胺。实验中还发现某些含吗啉基的丙烯酸酯类聚合物的水溶液及其水凝胶具有温度敏感性。本文合成了以下四种含吗啉基丙烯酸酯类单体:  相似文献   

17.
轻度交联的聚甲基丙烯酸2-羟乙酯(HEMA)是众所周知的医用水凝胶,即所谓的“Hvdron”。但其吸水率一般在59%(EWC为37%),并不尽人意。近年来,为了提高这类水凝胶的亲水性及生物相容性,常用一些亲水性的烯类单体进行表面改性或通过共聚以达到此目的,N-乙烯基吡咯烷酮是较为常用的这类单体之一。本文合成了含吡咯烷酮基丙烯酸酯类的单体,即丙烯酸2-N-吡咯烷酮基乙酯(PyEA),甲基丙烯酸2-N-吡咯烷酮基乙醋(PyEMA),并研究了这两种单体在甲基丙烯酸二甲氨乙酯(DMAEMA)与过硫酸钾(KPS)所组成的氧化还原引发体系下的聚合。  相似文献   

18.
The synthesis, characteristic ratio C and glass transition temperature (Tg) of poly(tetrahydrofurfuryl acrylate) (PTHFA) and of poly(2-ethylbutyl acrylate) (P2EBA) are reported. P2EBA has slightly lower flexibility (C = 9.2) than PTHFA (C = 8.6), mainly because of the higher bulkiness of its side group and the closer proximity to the main chain. The C results compared with the corresponding polymethacrylates show an increase in flexibility due to the absence of the α-methyl group. Comparison with poly(methyl acrylate) clearly shows the influence of the bulkiness of the side group on the chain flexibility. The lower Tg of P2EBA than that of PTHFA may be explained by the higher flexibility of the 2-ethylbutyl side group. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 1589–1592, 1997  相似文献   

19.
The copolymer composition of N-vinyl-2-pyrrolidone/butyl acrylate (V/B) copolymers was determined from the quantitative 13C{1H} NMR spectra. The monomer reactivity ratios for N-vinyl-2-pyrrolidone (V) and butyl acrylate (B) were found to be rV=0.11±0.07, rB=0.54±0.19, using the Kelen–Tudos and non-linear least-square error-in-variable (EVM) methods. The 13C{1H} and 1H NMR spectra of these copolymers are overlapping and complex. The complete spectral assignment of the carbon and proton NMR spectra were done by employing distortionless enhancement by polarization transfer (DEPT) and two-dimensional (2D) 13C–1H heteronuclear single quantum correlation spectroscopy experiments. The 2D total correlation spectroscopy (TOCSY) (1H–1H homonuclear TOCSY) NMR spectrum was used to ascertain the various geminal and vicinal couplings in the copolymer.  相似文献   

20.
The application of atom transfer radical polymerization (ATRP) to the homopolymerization of 2-hydroxyethyl acrylate, a functional monomer, is reported. The polymerizations exhibit first-order kinetics, and molecular weights increase linearly with conversion. Polydispersities remain low throughout the polymerization (Mw/Mn ≈ 1.2). Reactions were conducted in bulk and in 1 : 1 (by volume) aqueous solution; the latter demonstrates the resilience of ATRP to protic media. Analysis of poly(2-hydroxyethyl acrylate) by MALDI-MS and 1H-NMR shows Mn,exp to be much closer to Mn,th than those observed by SEC using polystyrene standards. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1417–1424, 1998  相似文献   

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