聚4-乙烯基吡啶的合成与表征

以过氧化二苯甲酰(BPO)为引发剂,用悬浮聚合的方法制备了较高相对分子质量的聚4 乙烯基吡啶(P4VP)。通过对聚合产物相对分子质量测试结果的分析,研究了单体与水的体积比、引发剂用量、分散剂用量、反应时间、反应温度、搅拌速度等因素对4 VP聚合反应的影响。结果表明,聚合时间为1h、聚合温度为60℃、引发剂的质量分数(占单体量)为0.8%左右、分散剂的质量分数(占单体量)为0.6%、搅拌速度为300r/min时,P4VP的重均分子量就能达到6×105～9×105。另外,采用紫外吸收光谱(UV)、红外吸收光谱(IR)、核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)、热重 差热分析(TG DTA)等测试手段研究了P4VP的结构和性能。     

2-乙烯基吡啶的合成研究

研究了以2-羟乙基吡啶为原料,经脱水反应合成2-乙烯基吡啶的实验方法。探讨了反应过程中催化剂、反应温度、反应时间等影响因素,得出了适宜的反应条件:在固体氢氧化钾催化下,n(氢氧化钾)∶n(2-羟乙基吡啶)=0.2∶1,反应时间1~1.5 h,反应温度100℃,收率达到85%以上,产品纯度大于98%。反应过程催化剂采用循环套用的方法,减少了原料消耗,降低了生产成本,具有较强额实际生产意义。     

胶束共聚合法合成丙烯酰胺/4-乙烯基吡啶共聚物

以十二烷基苯磺酸钠为表面活性剂 ,过硫酸钾 /亚硫酸氢钠为引发剂 ,进行丙烯酰胺 - 4-乙烯基吡啶胶束共聚合 ,合成了双亲共聚物 ,用1H NMR分析法、差示扫描量热量 ( DSC)对其进行表征 ,并分析了共聚物形成机理。     

乙烯基吡啶-偏二氯乙烯共聚物的合成与表征

以过氧化二苯甲酰（BPO）为引发剂,以羟乙基纤维素（HEC）为分散剂,采用悬浮聚合方法合成了乙烯基吡啶-偏二氯乙烯共聚物,然后采用特性粘数、UV、FT-IR、1H-NMR、DSC、TG等测试手段研究了乙烯基吡啶-偏二氯乙烯共聚物的结构和性能。     

4-乙烯基-4’-甲氧基二苯甲酮的光聚合性能研究

用萃取法研究了4-乙烯基-4’-甲氧基二苯甲酮(4-VMBP)和二苯甲酮(BP)在固化膜中的残留量;用实时红外法研究了4-VMBP的光聚合动力学,考察了胺浓度、引发剂浓度、灯距、氧阻、固化方式对氨基丙烯酸酯6116固化时间的影响。结果表明4,-VCBP固化残留量比BP小一个数量级;4-VMBP和三乙醇胺(TEOA)匹配性最好;固化体系中4-VMBP和TEOA质量分数均为4%时较为合适;隔绝空气条件下,固化时间缩短;灯距从10 cm调到20 cm,固化时间延长2倍多;间歇固化时间是连续固化的2倍多。     

2-乙烯基吡啶的合成方法

本文介绍了2-乙烯基吡啶的性质、用途,阐述了2-乙烯基吡啶合成的各种方法,并对这些合成方法进行分析比较,得出了合理的工艺路线及适宜的工艺条件。     

聚(丙烯酸钠-4-乙烯基吡啶)的表征

为了改善生物分解性能，在聚丙烯酸钠主链上引入了少量4-乙烯基吡啶，并对共聚产物进行了IR、UV、元素分析、热稳定性、螯合性能、分散性能等研究。结果表明，共聚产物中原来的吡啶环已经质子化，形成两性离子聚合物，聚合物的热稳定性随着原料中4-乙烯基吡啶含量的增加而下降，当4-乙烯基吡啶的物质的量分数为6％左右时，共聚物的粘均分子量大约1．3万，共聚物具有较好的螯合性能和分散性能。     

2-甲基吡啶合成2-乙烯基吡啶

以二苯胺生产过程中产生的副产物2-甲基吡啶为原料,以KOH改性的HZSM-5沸石分子筛为催化剂,气相一步法合成了2-乙烯基吡啶。考察了催化剂的焙烧温度、用于改性的钾含量、成型过程中的粘结剂的种类和含量,反应的工艺条件等因素对反应的影响。实验结果表明,催化剂焙烧温度为550℃,改性钾离子的质量分数为3%,以硅溶胶作为粘结剂进行催化剂成型,硅溶胶的用量为K-HZSM-5质量的50%,当反应温度为360~370℃,原料2-甲基吡啶和甲醛摩尔比为1∶3,质量空速0.75 h-1时,2-甲基吡啶的转化率可达到80.26%,2-乙烯基吡啶的选择性可达到97.59%,实现了副产物的有效利用。     

4-羟基吡啶的合成

在乙酸乙酯存在下 ,吡啶和SOCl2 进行缩合反应制得氯化N (4 吡啶基 )吡啶盐酸盐 ,再经过水解即得 4 羟基吡啶 ,总收以吡啶计为 2 3 2 %。     

4-吡啶乙酸盐酸盐的合成研究

介绍了标题化合物的合成方法。以4-氯吡啶盐酸盐为起始原料,先与丙二酸二乙酯反应,再用盐酸水解脱羧得到目标化合物,并经MS和1H NMR对其结构进行了表征。本合成路线原料易得、操作简便,易于实现工业化生产。反应总收率37%。     

Synergistic Influence of Poly(4-Vinylpyridine) and Potassium Iodide on Inhibition of Corrosion of Mild Steel in 1M HCl

The corrosion and inhibition behavior of mild steel in 1 M HCl in the presence of poly(4-vinylpyridine)(P4VP) and potassium iodide (KI) was investigated using weight loss measurements, potentiodynamic polarization studies and impedance measurements. The inhibition efficiency increased with increasing P4VP concentration. The inhibiting action of P4VP is considerably enhanced by the addition of potassium iodide. The adsorption of this compound either alone or in combination with iodide ions on the metal surface is found to obey Lamgmir's adsorption isotherm. The experimental results suggest that the presence of iodide ions in the solution increases the surface coverage and, therefore, indicate the joint adsorption of P4VP and iodide ions. On the other hand, it was found that the inhibiting effect of P4VP and (P4VP + KI) increased with increasing temperature of the corrosion medium. The presence of these species in the solution decreases the double layer capacitance and increases the charge transfer resistance, both derived from Nyquist plots obtained from a.c. impedance studies. The variation of charge transfer resistance with time suggests that the inhibitive action of (P4VP + KI) depends mainly on the protective inhibitor film formed on the steel surface.     

聚4-乙烯基吡啶对碲化镉量子点的表面改性

用巯基丙酸为配体合成了碲化镉(CdTe)量子点。以聚丙烯酸(PAA)为桥梁合成了聚4-乙烯基吡啶-碲化镉(P4-VP-CdTe)复合纳米粒子。通过红外光谱(IR)和透射电镜(TEM)紫外-可见吸收光谱(UV-Vis)、荧光发射光谱(PL)对其对其进行表征。结果表明,PAA能有效的促进P4-VP与CdTe的复合,这种复合结构的形成有效的改善了CdTe的稳定性及光学性质。     

Synthesis, Characterization and Catalytic Properties of Coordination Complexes Based on [Mo(CO)3(CH3CN)3] and Poly(4-vinylpyridine)

The synthesis, characterization, and catalytic properties of the zero-valent, group six metal complex formed by the reaction of [Mo(CO)₃(CH₃CN)₃] and poly(4-vinylpyridine) (P(4-VP)) is described in this work. The pyridyl groups of the organic polymer are covalently bonded to the Mo centers as suggested by X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) techniques. The polymer-immobilized metal catalyst was also characterized by DTA–TGA, differential scanning calorimetry (DSC) analysis and its morphology and elemental analyses were studied by scanning electron microscopy/energy dispersive X-ray (SEM/EDX) techniques. In the presence of 2-ethoxyethanol the solid is an active catalyst for the heterogeneous hydrogenation of styrene to ethyl benzene.     

Miscibility and intermolecular specific interactions in blends of poly(hydroxyether of bisphenol A) and poly(4-vinyl pyridine)

The blends of poly(hydroxyether of bisphenol A) (phenoxy) with poly(4-vinyl pyridine) (P4VPy) were investigated by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and high-resolution solid-state nuclear magnetic resonance (NMR) spectroscopy. The single, composition-dependent glass transition temperature (T_g) was observed for each blend, indicating that the system is completely miscible. The sigmoid T_g-composition relationship is characteristic of the presence of the strong intermolecular specific interactions in the blend system. FTIR studies revealed that there was intermolecular hydrogen bonding in the blends and the intermolecular hydrogen bonding between the pendant hydroxyl groups of phenoxy and nitrogen atoms of pyridine ring is much stronger than that of self-association in phenoxy. To examine the miscibility of the system at the molecular level, the high resolution ¹³C cross-polarization (CP)/magic angle spinning (MAS) together with the high-power dipolar decoupling (DD) NMR technique was employed. Upon adding P4VPy to the system, the chemical shift of the hydroxyl-substituted methylene carbon resonance of phenoxy was observed to shift downfield in the ¹³C CP/MAS spectra. The proton spin-lattice relaxation time T₁(H) and the proton spin-lattice relaxation time in the rotating frame T_1ρ(H) were measured as a function of the blend composition. In light of the proton spin-lattice relaxation parameters, it is concluded that the phenoxy and P4VPy chains are intimately mixed on the scale of 20-30 Å.     

Pervaporation of nonaqueous ethanol azeotropes through interpenetrating polymer network membranes prepared from poly(4-vinylpyridine) and poly(vinyl alcohol)

Highly hydrophilic interpenetrating polymer network (IPN) membranes were prepared from a mixture system of poly(4-vinylpyridine) (P4VP) and poly(vinyl alcohol) (PVA) by quaternizing crosslinking of P4VP with 1,4-dibromobutane (DBB) and simultaneous crosslinking of PVA with hexamethylene diisocyanate (HMDI). The membrane performance in pervaporation (PV) for the azeotropic mixture of ethanol with a less polar organic liquid (chloroform, benzene, carbon tetrachloride, and cyclohexane) was investigated. The strength of these IPN membranes was higher than that of the cellulose acetate membrane and depended on the membrane composition. All the membranes were ethanol permselective for the azeotropic feeds and equimolar mixture feeds as well. Only the swelling degree Q of the membrane, among several physicochemical factors, showed a relationship with the separation performance for the four feeds; a lower value of Q generally corresponded to a higher separation factor and smaller permeability. The membrane composition, which exhibited an optimum membrane performance, was examined in detail for some membranes. Both the separation factor for sorption and that for diffusion far exceeded unity, but the latter was greater in most cases than was the former and dominated the overall separation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2729–2738, 2001     

Synthesis and characterisation of poly(arylene sulphides): Part 11. Preparation of poly(1,4-phenylene sulphide) directly from bis(4-bromophenyl) disulphide

Reaction conditions for the preparation of poly(1,4-phenylene sulphide) (PPS) directly from bis(4-bromophenyl) disulphide (BBD) have been established. Reactions were performed in a boiling quinoline/pyridine solvent mixture (91% by vol. quinoline) in the presence and absence of copper powder. Reaction products were fractionated and the fractions characterised using elemental analysis, IR and NMR spectroscopy, viscometry, hot-stage microscopy, differential scanning calorimetry, thermogravimetry and curing studies. The yields and properties of the polymeric fractions are compared to those of similar fractions obtained from preparation of PPS by solution polymerisation of copper(I) 4-bromobenzenethiolate under conditions which correspond to those employed in this work. PPS was not produced, and BBD was almost quantitatively recovered when copper was absent from the reactants. Reactions performed using an equimolar ratio of copper to BBD produced PPS of molar mass approximately 2–4 × 10³ gmol^?1 in 76% yield after 8h reaction. However, this PPS was contaminated with an insoluble infusible material which had a deleterious effect on the physical properties of derived cured PPS materials. The yield of PPS decreased and the quantity of contaminant increased as reaction time increased. PPS of molar mass approximately 10⁴g mol^?1 was obtained in 50–60% yield, free from insoluble infusible material, when the molar ratio of copper: BBD was increased to 2:1; it exhibited normal properties on curing.     

4-三氟甲氧基苯基-氨基甲酸甲酯的催化合成

常压下,从4-三氟甲氧基苯胺出发,以碳酸二甲酯(DMC)为甲氧羰基化试剂,在不添加其他任何辅助试剂条件下催化合成4-三氟甲氧基苯基氨基甲酸甲酯(TFMPC)。系统研究了负载型和非负载型催化剂、反应温度、反应时间对合成的影响,发现ZrClO2/SiO2在后处理和催化剂再生方面均比Zn(OAc)2/SiO2效果要好,同时在最佳工艺条件下可以得到较好的反应转化率和产品收率。     

WGSR catalyzed by cis-[Rh(CO)2(amine)2]PF6 heterogenised on poly(4-vinylpyridine)

This paper describes catalytic activation studies of the water–gas shift reaction by cis-[Rh(CO)₂(amine)₂]PF₆ (amine = 4-picoline, 3-picoline, 2-picoline, pyridine, or 2,6-lutidine) heterogenised on poly(4-vinylpyridine) in aqueous 2-ethoxyethanol. The effect of varying the nature of the amine was investigated. The rhodium complexes bearing 4-picoline (4-pic) ligands proved to be most active among those surveyed, and displaying turnover frequencies for hydrogen production of 8.9 mol of H₂ per mole of Rh per day for 9.4x10^-5 mol cis-[Rh(CO)₂(4-pic)₂]PF₆/1.00 g poly(4-vinylpyridine), P(CO) = 0.9 atm at 100°C. This revised version was published online in July 2006 with corrections to the Cover Date.