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1.
采用具有聚苯乙烯高分子链为配位基团的聚合催化剂,催化2,5-二溴-3-己基噻吩单体进行Kumada缩聚反应,利用一锅法制备了聚(3-己基噻吩)-聚苯乙烯嵌段共聚物。结果表明:采用一锅法,在室温、常压条件下进行一步聚合直接生成嵌段共聚物,反应过程简单,聚(3-己基噻吩)与聚苯乙烯嵌段对接率接近100%;与聚(3-己基噻吩)相比,聚(3-己基噻吩)-聚苯乙烯嵌段共聚物的结晶性能更好。  相似文献   

2.
宋长伟  汪瑾  程发祥  周正发 《广州化工》2010,38(12):12-14,17
基于GRIM法合成了高等规的聚3-己基噻吩(rr-P3HT),研究了反应中催化剂和格氏试剂用量、反应温度和时间对产物产率的影响。采用GPC、1H-NMR和TGA法对其结构进行表征,结果显示该聚合物具有高度的规整性和良好的热稳定性。通过紫外吸收光谱、荧光发射光谱表征了聚合物的光物理性能,其最大紫外吸收峰和相应的发射峰分别位于455nm和573nm。  相似文献   

3.
以2,5-二溴-3-己基噻吩和2,5-二溴吡啶为原料,采用格氏试剂法合成了3-己基噻吩-co-吡啶共聚物(P3HT-co-PY)。产物的结构通过对红外光谱(FT-IR)以及核磁共振谱(1H-NMR)的分析来表征确定,并且对合成温度、时间、催化剂用量进行了研究,结果显示在50℃,催化剂用量为0.8%eq mol下反应8 h时的聚合产率最高,达到34%。  相似文献   

4.
田乃林 《当代化工》2002,31(2):83-85,88
研究了 3 己基噻吩单体及 3 己基噻吩与 3 乙羧基噻吩电化学共聚合成的合成原理、合成条件及方法。对 3 己基噻吩与 3 乙羧基噻吩电化学共聚物的电导率、导电稳定性、溶解度、相对分子质量及红外光谱特性进行了测试和分析。结果表明 ,共聚物较单体分子量增大 ,性能得到明显改善 ,特别是导电稳定性和机械性能改善较大  相似文献   

5.
3-异烷氧基噻吩的合成   总被引:2,自引:0,他引:2  
以CuB r为催化剂,NMP为溶剂,在110℃下,3-溴噻吩与过量的甲醇钠反应2.5 h生成3-甲氧基噻吩,产率为82%。再以无水NaHSO4为催化剂,在108~115℃下,3-甲氧基噻吩分别与异丁醇、异戊醇、异辛醇发生取代反应合成了3-(2-甲基丙氧基)噻吩、3-(3-甲基丁氧基)噻吩、3-(2-乙基己氧基)噻吩,反应时间分别为:3、3.5、4h,收率分别为72%、67%、63%。这些化合物结构都通过IR、1HNMR和MS进行了表征,并对其进行了初步香味评价,结果表明,它们都具有基本肉香味的特征。  相似文献   

6.
黄金波  余爱农  孙宝国  余华 《化学世界》2006,47(8):477-480,483
以CuBr为催化剂,NMP为溶剂,在110°C条件下,先用3-溴噻吩与过量的甲醇钠发生取代反应合成3-甲氧基噻吩,收率为82.3%。再以无水NaHSO4为催化剂,用正戊醇与3-甲氧基噻吩反应,合成了3-戊氧基噻吩。通过正交反应研究了反应物摩尔比、反应时间、反应温度以及催化剂用量对合成3-戊氧基噻吩收率的影响,得出了最佳反应条件为:n(3-甲氧基噻吩)∶n(戊醇)=1∶1.1;反应时间3.5 h;反应温度115°C;催化剂用量:0.25%。然后根据合成3-戊氧基噻吩的最佳工艺条件并加以适当修改,合成了3-乙氧基噻吩、3-丙氧基噻吩、3-丁氧基噻吩、3-戊氧基噻吩、3-己氧基噻吩、3-辛氧基噻吩,收率分别为78.5%、73.5%、71.5%、69.7%、67.2%、64.3%。这些化合物结构都通过IR,1H NMR和MS进行了表征,并对其进行了初步香味评价。结果表明它们都具有基本肉香味的特征。  相似文献   

7.
分别以乙二醇、三羟甲基丙烷和季戊四醇为起始剂,经ε-己内酯开环聚合制备了一系列聚己内酯多元醇。探讨了反应温度、时间和催化剂等因素对合成反应的影响,并采用红外光谱(FTIR)、羟值滴定、凝胶渗透色谱(GPC)对聚己内酯多元醇进行了表征。结果表明,以无水乙酸锌为催化剂,且用量为己内酯单体摩尔分数的0.2%,在温度120℃条件下反应3~4 h,制备的多元醇为理想的聚己内酯多元醇,相对分子质量与设计值一致,而且具有相对分子质量分布窄、成本低的特点。  相似文献   

8.
以噻吩-2-甲醛为原料,与磷酰基乙酸三乙酯在氢化钠存在下反应制备3-(2-噻吩)丙烯酸乙酯,后通过水解制备3-(2-噻吩)丙烯酸,总收率78.5%,纯度98.6%,可制备121 g每批。考察了原料滴加速度、物料摩尔比、溶剂用量、柱层析硅胶用量对化合物2合成的影响,确定了最佳条件为:滴加速度8 m L/min、噻吩-2-甲醛与膦酰基乙酸三乙酯摩尔比为1:1.2,溶剂1.6 L,柱层析用硅胶与粗产物重量比为1:15,该步反应收率92.3%,水解后产物经重结晶获得纯品,收率85%。产物结构通过质谱、核磁鉴定正确。  相似文献   

9.
以阔叶浆纤维素为原料,钛酸四正丁酯为催化剂,离子液体1-丁基-3-甲基咪唑氯盐(BmimCl)为溶剂,均相条件下与ε-己内酯单体进行开环聚合制备纤维素-聚己内酯接枝共聚物,探讨了单体与催化剂用量、反应温度与时间等条件对纤维素接枝率的影响,并用热重分析、X-射线衍射、核磁共振氢谱等手段对接枝共聚物进行了表征。结果表明,当ε-己内酯与纤维素摩尔比为21 mol/mol,反应时间为24 h,反应温度为120℃,催化剂与纤维素质量比为12%时,纤维素的接枝率最高达到86.7%;纤维素接枝ε-己内酯后,纤维素结晶结构被破坏,热稳定性下降,核磁共振氢谱分析显示ε-己内酯在与纤维素接枝反应的同时发生了自聚反应,生成聚己内酯。  相似文献   

10.
以无水乙醇为溶剂,氨基磺酸催化2-噻吩甲醛、乙酰乙酸乙酯和尿素溶剂热合成含噻吩基的3,4-二氢嘧啶-2-酮衍生物。通过正交实验和单因素实验探究最佳反应条件。结果表明,n(2-噻吩甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1.0∶1.2∶1.5,催化剂用量0.29 g,反应温度90℃,反应时间2.5 h,产率可达76.5%;各因素对产率的影响程度:反应物摩尔比反应时间催化剂用量反应温度。在最佳反应条件下,合成了一系列3,4-二氢嘧啶-2-酮衍生物,均有较好产率。  相似文献   

11.
酸性离子液体催化合成三醋酸甘油酯   总被引:2,自引:0,他引:2  
合成了[HSO3-pmim]Cl、[HSO3-pmim][H2PO4]、[HSO3-pmim][BF4]和[HSO3-pmim] [HSO4]离子液体,用1H-NMR和FT-IR对离子液体的结构进行了确定。将几种酸功能化离子液体应用于三醋酸甘油酯的合成反应中,筛选出了一种催化效果好又可以重复使用的离子液体[HSO3-pmim][HSO4]。考察了催化剂用量、原料配比和反应时间对反应的影响,得到了较佳反应条件:n(甘油)∶n(醋酸)=1∶8,催化剂用量为醇酸总质量的5.8%,反应时间6 h,反应温度(80~90) ℃。对该功能化离子液体的重复使用性进行了考察,重复使用10次后,三醋酸甘油酯的收率仍大于90%。  相似文献   

12.
The overall crystallization rates of poly (3‐hexyl thiophene) (P3HT) cocrystals with different amount of regioregularity of the components are measured using differential scanning calorimetry (DSC). Two pairs of cocrystals with varying compositions of the component polymers (viz P3HT(R) (regioregularity 92 mol %)/P3HT‐2 (regioregularity 82 mol %), and P3HT‐2/P3HT‐1 (regioregularity 75 mol %)) are used. The crystallization rate at the same isothermal crystallization temperature (Tc) decreases with increasing regioregularity. The low Avrami exponent values (0.15–1.0) in all the samples suggest the presence of rigid amorphous portion, which cannot diffuse out quickly from the crystal growth front (soft impingement). Analysis of crystallization rate using Laurintzen–Hoffman (L–H) growth rate theory indicates Regime I to Regime II transition in all the samples. The product of lateral and end surface energy values (σσe) increases gradually with increasing regioirregularity in the blend. Analysis of σ values indicates chain extension of the components in the melt of the blend and the entropy of activation (ΔSI–II) of the cocrystals are higher than those of the components. The entropy of cocrystallization (ΔSc) values are 1–2.4 e.u for P3HT(R)/P3HT‐2 system and 0.5–1 e.u for P3HT‐2/P3HT‐1 system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3811–3820, 2006  相似文献   

13.
BACKGROUND: The highest efficiencies of bulk‐heterojunction solar cells from poly(3‐hexylthiophene) (P3HT) and [6,6]‐phenyl C61‐butyric acid methyl ester (PCBM) reported so far are close to 6%. Phenomena occurring during the photovoltaic process, such as the creation, diffusion and separation of excitons, as well as charge carrier transport, are governed by the active layer morphology. The latter phenomenon, which depends on the self‐organization of P3HT, can be influenced by its degree of regioregularity. The aim of this work is to clarify the relationship between the regioregularity of P3HT, the composition of P3HT/PCBM blends and the performances of photovoltaic devices. RESULTS: Two types of P3HTs with different degrees of regioregularity have been synthesized and used as active layers with PCBM in photovoltaic cells. The higher performances in photovoltaic devices are obtained for high‐regioregular P3HT and can be explained considering the self‐organizing properties of high‐regioregular P3HT, leading to higher sunlight absorption and higher hole mobilities. In addition, this report demonstrates the importance of the ratio of P3HT versus PCBM in correlation with the regioregularity of P3HT on the optical properties, charge transport and characteristics of photovoltaic cells. CONCLUSION: We have investigated the dependence of the photovoltaic properties of P3HT/PCBM blend‐based photovoltaic devices on the degree of regioregularity of P3HT. We find that the best performance is exhibited by devices based on highly regioregular P3HT. Also, the best performances are not obtained for the same P3HT:PCBM weight ratios for high‐regioregular P3HT (1:0.8) and low‐regioregular P3HT (1:3). Copyright © 2007 Society of Chemical Industry  相似文献   

14.
Poly (3‐hexylthiophene) (P3HT) synthesized by oxidative polymerization was fractionated by molecular weight by using organic solvents. The fraction of higher average molecular weight gave higher regioregularity and conductivity. Composites of the P3HT fraction having the highest molecular weight were prepared by use of the following conducting particles as fillers: titanium carbide (TiC), indium tin oxide (ITO), and carbon black (CB). Temperature‐conductivity profiles of the composites showed that the resistance change with PTC (positive temperature coefficient) effect was strongly influenced by the content and size of conducting particles and the molecular weight of P3HT. Although no significant PTC effect for P3HT‐CB composite and little effect for P3HT‐ITO composite system were observed, the P3HT‐TiC composite containing TiC of 70–80 wt % showed an obvious PTC effect that brought the conductivity change by about four orders of magnitude near the glass transition temperature of P3HT. However, such a remarkable PTC effect was not observed for the P3HT‐TiC composite prepared with the P3HT fraction of low‐molecular weight. It was shown that a good PTC effect could be achieved by the composite consisting of the P3HT of high‐molecular weight and the conducting particles of relatively large size. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3069–3076, 2000  相似文献   

15.
Polyalkylthiophenes are applied in the form of thin films as active layers in organic devices. The main properties defined in the synthetic procedure that can affect the film formation are the molar mass and regioregularity degree (the content of head-to-tail, HT, linkages). These properties can be varied, at principle, by changing the conditions of the oxidative polymerization process. In this work, we evaluate the effect of oxidant addition rate, temperature and time-dependence of poly-(3-hexylthiophene), P3HT, oxidative polymerization in molar mass and regioregularity degree, besides other polymer properties such as absorption and emission of visible light. The results show that the polymer started to grow during the oxidant addition and already presents a relatively high molar mass (ca. 10,000 g/mol) just after the addition stopped. Polymerization temperature is more significant in molar mass variations than the time expended for the polymerization reaction, with values of Mw ranging from 15,000 to 70,000 g/mol in the conditions tested. The HT contents were all above 70 %, with higher variations in the two first hours of polymerization reaction and are mainly defined during the oxidant addition, which leads to higher HT contents and narrower molar mass distributions using slower additions. The solvent extraction reveals that the HT content is directly related to the polymer chains extension, being possible to improve both regioregularity degree and molar mass of P3HT.  相似文献   

16.
以海绵铂为原料合成出[Pt(NH36]Cl4络合物,采用热重分析(TG)、扫描电镜-能谱(SEM-EDS)、紫外-可见分光光度计(UV-Vis)、质谱(MS)、X射线光电子能谱(XPS)等手段确定了[Pt(NH36]Cl4的结构组成;以H2PtCl6、Pt(NH34Cl2和[Pt(NH36]Cl4为前驱体,采用等体积浸渍法制得Pt/Beta催化剂,采用X射线衍射(XRD)、X射线荧光光谱(XRF)、氨程序升温脱附(NH3-TPD)、氢氧滴定(H2-O2)、透射电镜(TEM)、氢气程序升温脱附(H2-TPD)等表征了Pt/Beta催化剂的物化性质,并考察了Pt/Beta催化剂的多环芳烃选择性开环性能。结果表明,[Pt(NH36]Cl4络合物具有更高的“抗自还原”能力,可从前驱体结构上降低铂氨前驱体受热分解时的自还原现象。前驱体结构对铂纳米颗粒的几何尺寸及分布有较大影响,一方面络合物的价态显著影响前驱体与分子筛间的静电作用,进而影响铂纳米颗粒的落位与尺寸;另一方面络合物的空间结构影响前驱体在分子筛微孔中的分布,影响铂纳米颗粒的Ostwald熟化速率。前驱体结构可调变Pt/Beta催化剂的双功能匹配关系,显著影响Pt/Beta催化剂转化甲基萘的活性、稳定性,采用[Pt(NH36]Cl4前驱体制备的Pt/Beta催化剂具有更优的活性及长周期稳定性。  相似文献   

17.
制备了两种镍配合物二[N-(2-氧基-1-萘甲醛)缩-2,6-二异丙基苯胺]合镍[Ni(L1)2]和二[N-(2-氧基-1-萘甲醛)缩-邻甲基苯胺]合镍[Ni(L2)2]。研究了它们以普通烷基铝为助催化剂催化甲基丙烯酸甲酯(MMA)的聚合。结果表明,镍配合物的结构、聚合条件如单体浓度、Al与Ni物质的量比、聚合温度和聚合时间等对甲基丙烯酸甲酯聚合反应活性有很大的影响,当甲基丙烯酸甲酯浓度为0.8 mol·L-1、n(Al)∶n(Ni)=400、温度为0 ℃时,催化活性达到110.7 kg-PMMA·(mol-Ni·h)-1。随着聚合时间的延长,催化活性下降,而转化率则随着聚合时间的延长而缓慢增加。  相似文献   

18.
固定化Bronsted酸性离子液体催化酯化反应   总被引:1,自引:0,他引:1       下载免费PDF全文
设计合成了1-甲基-3-丁烷磺酸咪唑硫酸氢盐([(n-Bu-SO3H)MIm][HSO4])、1-甲基-3-丁烷磺酸咪唑对甲苯磺酸盐([(n-Bu-SO3H)MIm][p-CH3C6H4SO3])和硫酸三乙胺([Et3NH][HSO4])3种Bronsted酸性离子液体,考察了其催化正己酸与乙醇酯化反应的活性,分别采用浸渍法和溶胶-凝胶法将活性最佳的离子液体[(n-Bu-SO3H)MIm][HSO4]固定在硅胶上,对固定化离子液体催化正己酸与乙醇酯化反应的性能及重复使用性能进行了比较,并采用1H NMR、元素分析和FTIR等方法对其进行了表征。研究结果表明:采用浸渍法A、浸渍法B和溶胶-凝胶法固定的离子液体的负载量(质量分数)分别为15.5 %、20.5 %和40.5 %,催化正己酸与乙醇酯化反应所得正己酸乙酯的产率分别为75.3%、92.6%和92.6%。但浸渍法制备的固定化离子液体不稳定,重复使用4次(浸渍法A)和8次(浸渍法B)后离子液体负载量分别下降到3.0 %和7.0 %,正己酸乙酯产率分别降为24.2%和64.5%;而采用溶胶-凝胶法制备的固定化离子液体重复使用10次后,离子液体的负载量为39.0%,流失很少,正己酸乙酯产率依然高达92.7%。将溶胶-凝胶法制备的固定化离子液体进一步应用于其他脂肪酸与乙醇的酯化反应,乙酯产率均在90.0%左右,表明采用溶胶-凝胶法是制备固定化离子液体催化剂的有效方法。  相似文献   

19.
通过Williamson反应、Friedel-Crafts酰基化等反应合成了新型冠醚功能化离子液体1-烯丙基-3-(6′-氧代苯并-15-冠-5-己基)咪唑双三氟甲磺酰亚胺([A(benzo15C5)HIM][(CF3SO22N]),并以IR、1H NMR对其结构进行了表征。初步探讨了双酚A(BPA)在多壁碳纳米管-离子液体(MWCNTs-IL)修饰玻碳电极上的电化学行为。  相似文献   

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