溶度参数对聚α-烯烃油溶剂选择的影响

以溶度参数为溶剂选择依据,对α-癸烯齐聚制备润滑油基础油合成实验的溶剂进行研究.考察了不同溶度参数的溶剂对PAO的影响.将溶度参数的概念引入聚合反应溶剂的选择中.结果表明,溶剂种类对PAO的影响明显.由于环己烷的溶度参数接近聚合物,可作为聚α-烯烃油的理想溶剂.产物收率高,性能优良.     

溶剂对聚合物减阻剂流变行为和减阻性能的影响

采用博力飞旋转粘度计测定了减阻剂在不同溶剂中溶液的流变性能,通过减阻剂室内模拟环道评价装置测定了不同溶剂合成的聚合物的减阻率。结果表明,减阻剂属于典型的剪切增稠型非牛顿流体;减阻剂在不同溶剂中溶液的粘度随着温度升高而降低;当环己烷与减阻剂的溶度参数相等时,减阻剂在环己烷中的溶解性能最好。并探讨了剪切增稠流体的减阻机理,分析了不同溶剂合成的减阻剂对减阻性能的影响。     

计算机模拟在聚α-烯烃减阻剂合成中的应用

根据溶度参数理论,应用分子模拟软件Materials Studio 6.0研究在不同溶液配比下,混合溶剂的溶度参数值。根据模拟结果筛选溶剂,合成减阻剂样品。通过室内环道评价装置、红外、核磁碳谱以及XRD测试对样品进行表征和结构分析,发现当混合溶剂的溶度参数无限接近聚合物的溶度参数时,合成的减阻剂有更高的减阻增输效果。表明溶度参数理论可以作为实验指导,而模拟手段的加入可以简化实验步骤。     

正交试验在预聚合法合成减阻剂中的应用

在管输油品中加入减阻剂是提高管线输送能力的有效方法。以TiCl4/Al（i—Bu）3为引发体系,用本体预聚合法引发α-烯烃聚合。利用正交试验法确定聚合物的合成条件,分析了预聚合时间、预聚合温度、前后助化剂体积比等因素对聚合产物减阻性能的影响。环道测试结果表明,在优化的合成工艺条件下,能够合成减阻率为50．67％（添加量为10mg／L）,增输率为47．5％的聚合物。     

中国专利

溶液法乙烯聚合的控制一种制备高分子量α-烯烃聚合物的溶液法,该聚合物选自乙烯均聚物和乙烯与C_3～C_(12)的较高级α-烯烃的共聚物,在含钛配位催化剂存在下,在惰性溶剂中,超过105℃温度的非等温条件下使乙烯和/或乙烯与C_3～C_(12)较高级α-烯烃的混合物在操作条件于不同的管     

聚α-烯烃油品减阻剂减阻性能研究

以1-癸烯为聚合单体,在Ziegler-Natta催化剂TiCl3/AlR2Cl上进行α-烯烃催化聚合研究,考察了主催化剂和助催化剂用量、聚合反应温度及聚合物相对分子质量对聚α-烯烃油品减阻剂减阻性能的影响,确定最佳减阻聚合工艺条件为V(1-癸烯)∶m(TiCl3)∶V(AlR2Cl)=100 mL∶50 mg∶0.25 mL,聚合反应温度为265 K,在该条件下减阻率为45.3%,为高性能减阻剂的工业化开发提供参考。     

聚氨酯包覆聚α-烯烃减阻剂微囊化工艺研究

在水溶液体系中,以2,4-二异氰酸酯与甘油为原料进行界面聚合,通过一步反应制备出聚氨酯包覆聚α-烯烃减阻剂微胶囊,并对工艺参数进行了优化,得到2,4-二异氰酸酯与甘油的摩尔比为3∶2,聚氨酯壁材用量与聚α-烯烃颗粒用量比为2%,表面活性剂用量为水量的0.5%,聚α-烯烃减阻剂粉粹至90~100目,常温反应30min。性能测试结果表明:制备的α-烯烃聚氨酯微胶囊具有良好的表观形貌性状、减阻性能优异、并具有优良的存储稳定性。     

中国专利

乙烯聚合负载型含铬催化剂及制备方法 本发明涉及1种用于乙烯均聚或乙烯与α-烯烃共聚的负载型含铬催化剂及制备方法。此催化剂具有高活性,能生产分子量可调、分子量分布较宽的乙烯聚合物。本发明的催化剂是以有机铬化合物作原料,在液态烃溶剂中负载到载体上,负载     

原位聚合法制备聚α-烯烃减阻剂微囊的工艺研究

以聚α-烯烃为囊心,以水和阴离子表面活性剂为分散系统、聚脲甲醛为壁材,采用原位聚合法制备出性能稳定的聚α-烯烃减阻剂微胶囊。利用红外光谱(IR)、扫描电镜(SEM)对微胶囊进行表征,对合成工艺参数进行了优化。结果表明,优化工艺为:尿素与甲醛的摩尔比为1∶2,聚脲甲醛壁材的加入量为10%,表面活性剂量为水量的0.5%,聚α-烯烃减阻剂粉粹至90~100目,用硫酸调节体系的pH为3,60℃反应2 h。制备的α-烯烃聚脲甲醛微胶囊的表观形貌得到了有效的改善、减阻性能及存储稳定性优异。     

原位聚合法制备聚α-烯烃减阻剂微囊的工艺研究

以聚α-烯烃为囊心,以水和阴离子表面活性剂为分散系统、聚脲甲醛为壁材,采用原位聚合法制备出性能稳定的聚α-烯烃减阻剂微胶囊。利用红外光谱(IR)、扫描电镜(SEM)对微胶囊进行表征,对合成工艺参数进行了优化。结果表明,优化工艺为:尿素与甲醛的摩尔比为1∶2,聚脲甲醛壁材的加入量为10%,表面活性剂量为水量的0.5%,聚α-烯烃减阻剂粉粹至90¹00目,用硫酸调节体系的pH为3,60℃反应2 h。制备的α-烯烃聚脲甲醛微胶囊的表观形貌得到了有效的改善、减阻性能及存储稳定性优异。     

Physical-chemical studies of polyhexene-1. Some dilute solution properties

This work is a study of some dilute solution properties of polyhexene-1. Results with the following experimental measurements are reported: osmotic pressure, phase equilibrium, viscosity, light scattering, molecular weight, molecular weight distribution, and degree of chain extension. Three good solvents were used, cyclohexane, tetrahydrofuran, and toluene, and one poor solvent, phenetole, in order to obtain theta conditions. The properties of polyhexene-1 are compared with those of other α-olefin polymers reported in the literature.     

Copolymerization of ethylene with vinyl acetate. II. Effect of solvent on polymer yield and molecular weight

In the free-radical solution copolymerization of ethylene and vinyl acetate, polymer yield and molecular weight were found to vary considerably with the solvent used. Solvents were toluene, benzene, hexane, heptane, and cyclohexane. Molecular weights were highest in benzene and lowest in toluene and were readily explained by different solvent chain-transfer constants. Polymer yields were highest in aliphatic solvents and lowest in aromatic solvents including benzene. This was attributed to different types of interactions of the solvents with radical species. The saturated aliphatic solvents undergo hydrogen abstraction reactions, but these give reactive alkyl radicals which reinitiate polymer growth. Toluene also undergoes hydrogen abstraction reactions, but the resultant benzyl radical is resonance stabilized and does not readily reinitiate polymerization. Benzene does not undergo hydrogen abstraction reactions. The low yields are attributed to complex formation. A consideration of kinetic theory indicates that complex formation with both initiator and growing polymer radicals is involved. Differences in viscosity, ethylene solubility, and initiator half-life in the different solvents, as well as induced decomposition of the initiator, were not determining factors.     

Swelling of crosslinked polyacrylates in isotropic and anisotropic solvents

The purpose of this study was to examine the swelling and deswelling of photochemically crosslinked poly(n‐butylacrylate) networks in isotropic and anisotropic solvents. The phase diagrams were established in terms of composition and temperature for five isotropic solvents, acetone, cyclohexane, methanol, tetrahydrofuran, and toluene, and two low‐molecular‐weight nematic liquid crystals, 4‐cyano‐4′‐n‐pentyl‐biphenyl and an eutectic mixture of cyanoparaphenylenes. Networks were formed by ultraviolet curing in the presence of 0.5 wt % difunctional monomer (hexane diol‐di‐acrylate) and 0.5 wt % photoinitiator (Darocur 1173). Immersion in excess solvent allowed us to measure the solvent uptake by weight and to determine the size increase by optical microscopy in terms of temperature. We calculated weight and diameter ratios considering the swollen‐to‐dry network states of the samples. Phase diagrams were analyzed with the phantom network model according to the Flory–Rehner theory of rubber elasticity, and for the anisotropic solvents, modeling was supplemented with the Maier–Saupe theory of nematic order for free energy. The polymer–solvent interaction parameter was deduced as a function of temperature, but the values were in discrepancy with Fedors's model of solubility parameters, which overestimated the interaction. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1–9, 2004     

长链α-烯烃本体聚合制备油溶性减阻剂的研究

以负载型TiCl4/MgCl2为引发体系,在微正压条件下采用本体聚合法引长链α-烯烃聚合,制备高减阻性能的油溶性减阻剂(DRA).采用正交试验法考察了各项因素对聚合反应的影响,最终确定最优化的工艺条件.聚合物环道减阻测试的结果表明,在环道中添加的质量浓度为0.01 kg/m3时,减阻率高达55％.用乌氏粘度计测定了特性...     

Effect of porogenic solvent on the porous properties of polymer monoliths

Polymer monoliths with open pores and median pore size of about 15 nm–3 μm have been successfully synthesized by photoinitiated polymerization of butyl methacrylate and ethylene glycol dimethacrylate monomers. The solubility of the monomers in a porogenic solvent is determined by Hildebrand solubility parameter, and it is found that it has great effect on the pore size of the polymers synthesized. Polymers with larger pores are usually generated with poorer solvents for the monomers. However, polymers with different pore sizes and porosities have been obtained using porogenic solvents with similar Hildebrand solubility parameters. The evaporation rate of the porogenic solvents might be another critical factor affecting the properties of the polymer monoliths. Moreover, the effect of water as a cosolvent on the pore size and porosity of the polymers have also been investigated. Polymers with larger pore size have been prepared with the presence of water due to the occurrence of earlier phase separation in the polymerization. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Effect of solvent on anthraquinone-sensitized photopolymerization of methyl methacrylate

Photopolymerization of methyl methacrylate was carried out in the system containing anthraquinone (AQ) sensitizer and solvent under nitrogen at 30°C. Hydrocarbons, alcohols, and mixtures of both, for example, cyclohexane and isopropanol, were used as solvents. The maimum yield of polymerization was observed at a certain concentration of alcohol in hydrocarbon, a phenomenon which is discussed from measurements of polymer molecular weight and the UV spectrum of irradiated AQ.     

氯化聚乙烯接枝水溶性单体共聚物的双亲性

以疏水性弹性体氯化聚乙烯(CPE)接枝水溶性单体(丙烯酸AA,丙烯酰胺AM)合成双亲性接枝聚合物(CPE-g-AA,CPE-g-AM)。考察了接枝物的吸水率及亲水/亲油性能。研究发现,双亲性接枝聚合物吸水性能与接枝单体类型及其接枝率有关,接枝物在油/水混合液中的分散状况及吸水/油性能与接枝物的接枝率及所吸有机溶剂溶度参数(δ)有关,随极性单体接枝链含量增大,双亲性接枝物吸水性增强而吸油性降低。     

Synthesis and properties of a functional copolymer from N-ethylaniline and aniline by an emulsion polymerization

A series of functional copolymers was synthesized by an emulsion polymerization of N-ethylaniline (EA) and aniline (AN) in the presence of sodium dodecylbenzene sulfonate in HCl. Several important polymer parameters including the polymerization yield, molecular weight, solubility, film formability, solvatochromism, thermochromism, and alterable electrical conductivity were systematically studied by changing the comonomer ratio, emulsifier/monomer ratio, oxidant/monomer ratio, solvent, and temperature. The resulted copolymers were characterized in detail by infrared and UV-vis spectroscopies. It is found that these copolymers exhibit narrow molecular weight distribution, good solubility, excellent film flexibility, colorful solvatochromism in various solvents, reversible thermochromism in a wide temperature range, and widely controllable conductivity from 2.03×10⁻¹⁰ to 0.161 S/cm with changing the polymerization conditions and doping states.