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1.
含氟甲基丙烯酸酯聚合物中的氟原子可使其折光指数nD很低。这是光导纤维皮材的首要条件[1]。这类材料的大分子主链与作为芯材使用的聚甲基丙烯酸甲酯(PMMA)具有相同的结构,因此其间的相容性和粘结性好,有利于光的全反射;其热稳定性也好[2,3],可用于共挤出法制造塑料光导纤维.  相似文献   

2.
本文综述了目前2,3,3,3-四氟丙烯(HFO-1234yf)的合成路线,包括氟-氯交换、脱卤化氢、脱卤、脱卤醇、脱次氯酸乙酰酯、脱水、加氢脱卤、脱氢、高温热解、SF4参与的氟化反应、脱羧等。其中,以2-氯-3,3,3-三氟丙烯(HCFO-1233xf)为原料的氟-氯交换路线、以1,1,1,2,3-五氟丙烷(HFC-245eb)为原料的脱氟化氢路线和2-氯-1,1,1,2-四氟丙烷(HCFC-244bb)为原料的脱氯化氢路线均具有原料容易合成得到、容易实现气相连续化大规模生产的优势,具有工业化价值。另外,分析对这些路线拥有独立知识产权的氟化工企业现状,提出今后HFO-1234yf领域的研究重点。  相似文献   

3.
2,3,5,6-四氟苯甲醇的合成   总被引:3,自引:0,他引:3  
唐渝  屈伟月  杨骏 《有机化学》2005,25(9):1125-1128
经氟代、水解脱羧、酯化、还原等步骤合成了杀虫剂四氟苯菊酯的重要中间体2,3,5,6-四氟苯甲醇, 改进了氟代反应的无水操作和反应条件, 产物四氟对苯二甲腈纯度高达98.3%, 通过加入水参与反应改进了水解反应, 使水解和脱羧由两步反应变为一步, 且产物为只脱一个羧基的2,3,5,6-四氟苯甲酸, 收率可以高达92.5%, 用相对价廉的NaBH4/I2体系还原2,3,5,6-四氟苯甲酸甲酯以52.3%的收率得到了目标产物, 总收率29.6%.  相似文献   

4.
5.
制备了一系列CrOx-Y2O3催化剂用于气相氟化1,1,1-三氟-2-氯乙烷(HCFC-133a)合成1,1,1,2-四氟乙烷(HFC-134a), 并考察了Y(OH)3、YCl3和Y(NO3)3前躯体对催化剂性能的影响. XRD和UV-Vis光谱实验结果表明, Y前躯体对催化剂表面Cr物种有影响, 其中采用Y(OH)3前躯体的催化剂有利于以高分散的Cr6+形式存在. 研究表明CrOx-Y2O3催化剂在预处理和反应过程中, 部分高价CrOx可转化为CrF3. 催化剂中CrF3含量增加, 导致其转化为活性物种的含量相对减少, 所以其催化活性下降.  相似文献   

6.
制备了一系列CrOx-Y2O3催化剂用于气相氟化1,1,1-三氟-2-氯乙烷(HCFC-133a)合成1,1,1,2-四氟乙烷(HFC-134a),并考察了Y(OH)3、YCl3和Y(NO3)3前躯体对催化剂性能的影响.XRD和UV-Vis光谱实验结果表明,Y前躯体对催化剂表而Cr物种有影响,其中采用Y(OH)3前躯体的催化剂有利于以高分散的Cr6+形式存在.研究表明CrOx-Y2O3催化剂在预处理和反应过程中,部分高价CrOx可转化为CrF3.催化剂中CrF3含量增加,导致其转化为活性物种的含量相对减少,所以其催化活性下降.  相似文献   

7.
本文报道了由60℃自由基引发聚合得到的聚甲基丙烯酸-2,3,3-四氟丙酯,经浓硫酸水解而生成聚甲基丙烯酸。后者以重氮甲烷酯化,转化成聚甲基丙烯酸甲酯,并且分别作红外光谱、核磁共振波谱分析。根据分析结果推断聚甲基丙烯酸-2,2,3,3-四氟丙酯为无规立构聚合物,并与聚甲基丙烯酸正丙酯衍生而来的相应产物作比较。  相似文献   

8.
熊果酸与1,3-二溴丙烷反应制得中间体熊果酸-3’-溴代丙醇酯(1),含溴醇酯1与含氮化合物反应,合成了系列熊果酸含氮衍生物2a~2j,均未见文献报道,其结构经1H NMR,13C NMR,IR,MS确认.初步的抗肿瘤生物活性研究表明,部分化合物的抗肿瘤活性与熊果酸相比均有提高,其中化合物2e具有更强的抑制活性.  相似文献   

9.
由具有2位氢的3-氨基-2-烯丙亚胺与N-氯或N-溴琥珀酰亚胺以甲苯作溶剂在常温下反应,制备了-些未见文献报道的2-氯和2-溴-3-氨基-2-烯丙亚胺,化合物结构均经元素分析,^1H NMR,^13C NMR和MS确证。  相似文献   

10.
本文报道了用GC/FTIR方法分析气相催化氨化合成的CFC12的替代物HFC134a粗产品、中间体及副产物的化学组成。该法选择石英PLOTAl2O3柱(35mX0.32mm)分离、FID检测。分析结果表明:上述样品基本上是C1~C2的CFCs复杂混合物。由于采用不分流进样、不加补偿气、适当增大进样量及计算机差谱等技术,使各种样品的可检出组分合计达24种以上并确定了其中20种组分的分子结构。已确定组分一般都占所分析样品色谱总馏出峰面积的95%以上。  相似文献   

11.
丙烯酸卤代烷酯是重要的精细化工原料和中间体,一般的合成方法是直接酯化法。已有文献报道采用酯交换工艺以丙烯酸甲酯为原料制备丙烯酸高碳烷酯和丙烯酸二甲氨基烷酯[1-4]。Nolan等人曾报道了氮杂环卡宾作为催化剂通过酯交换反应合成甲基丙烯酸卤代烷酯[5,6],但是其催化剂制备  相似文献   

12.
以2-溴代异丁酸乙酯(EBiB)为引发剂、CuBr/CuBr_2/1, 10-邻二氮菲( phen)配合物为催化剂,在水分散体系中进行了丙烯酸四氟丙酯(TFPA)与苯乙烯 (St)的原子转移自由基共聚合,所得共聚物的分子量(M_n)随着单体总转化率的 增加而增大,分子量分布(M_w/M_n)较窄(1.26~1.65),表现出“活性”聚合 的特征。用拓展的Kelen-Tudos法和Fineman-Ross法估算了共单体的表观竞聚率, 发现St的相对反应活性高于TFPA,因此当St和TFPA起始组成为1:1(摩尔比)时, 反应自发生成了含氟的准梯度或“渐变”共聚物。实验分别考察了三种乳化剂体系 ,即十二烷基磺酸钠(SLS)、全氟辛酸钠(SPFS)/SLS和全氟壬烯氧基苯磺酸钠 (OBS)/SLS对共聚合反应的影响,发现它们对共聚合的可控制性影响不大,且反 应过程中均无破乳现象发生;然而,以OBS/SLS复合乳化剂体系制备的共聚物乳液 的贮存稳定性明显优于以SLS或SPFS/SLS为乳化剂体系制备的共聚物乳液的稳定性 。  相似文献   

13.
符柳娃  苏嘉辉  严佳进  张婷  杨妍  刘晓暄 《应用化学》2018,35(12):1434-1441
选取十二烷基硫酸钠(SDS),辛基苯基聚氧乙烯醚(OP-10)为复合乳化剂,过硫酸钾(KPS)为引发剂,将2-(全氟己基)乙基甲基丙烯酸酯(PFM)与丙烯酸酯类单体采用预乳化-半连续种子乳液聚合法进行乳液共聚,再将羟基螺吡喃(SPOH)与乳液进行物理共混,制得光致变色含氟丙烯酸酯乳液。 通过多种表征手段研究丙烯酸正丁酯(n-BA)和甲基丙烯酸甲酯(MMA)软硬单体的质量比,SPOH的用量对聚合反应和乳胶膜性能的影响。 结果表明,加入含氟单体后乳胶膜与水、油的接触角提高,热稳定性提高;加入SPOH的质量分数为1.25%时,乳胶膜具有较好的光致变色性能。  相似文献   

14.
Poly[2-(dimethylamino)ethyl acrylate] (PDAEA) and polymer complexes of 2-(dimethylamino)ethyl acrylate (DAEA) with nickel(II), copper(II), iron(III) and cobalt(II) chlorides were prepared and characterized by means of IR, electronic spectra and elemental analysis. The thermal stability of the homopolymer was compared with those of the polymer complexes, and the order of stability was given. The activation energies of the polymer complexes were calculated.  相似文献   

15.
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   

16.
Preparation and characterization of a novel fluorinated acrylate resin   总被引:1,自引:0,他引:1  
The novel fluorinated acrylate resin was successfully prepared by solution polymerization of 2-(perfluoro-(1,1-bis-isopropyl)-2-propenyl)oxyethyl methacrylate (POMA) with butyl acrylate (BA), methyl methacrylate (MMA) and methacrylic acid (MAA) initiated by AIBN in the co-solvents of ethyl acetate, butyl alcohol and toluene. POMA was synthesized from the intermediate perfluoro nonene and 2-hydroxyethyl methacrylate as the staring reactants. Films of the novel fluorinated acrylate resin were prepared by coating the resin directly on the clean glass sheet and allowed to dry at room temperature. The characteristics of the film such as hydrophobicity, glass transition temperature and thermal stability were characterized with the contact angle, differential scanning calorimetry and thermo-gravimetric analysis respectively. The structure of the novel fluorinated acrylate resin was investigated by Fourier transform infrared (FTIR) spectrometry. The influences of the fluorine content on the performance of the acrylate resin were studied. Results show that the hydrophobicity, chemical resistance, glass transition temperature and thermal stability of the acrylate resin are improved when the fluorinated monomer is introduced to copolymerize with other monomers. However, the hydrophobicity of the fluorinated acrylate resin is improved slightly via annealing.  相似文献   

17.
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   

18.
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   

19.
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   

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