Flow improvement of Liaohe extraheavy oil with comb‐type copolymers

Liaohe extraheavy oil is a kind of special crude oil with high paraffin and asphaltene contents and a pour point of up to 60°C. To improve its flowability, comb‐type poly(maleic alkylamide‐co‐α‐octadecene) copolymers (MACs) with various amidation ratios were synthesized and used. Model oils containing paraffin mixtures with the same average carbon number to Liaohe extraheavy oil with and without asphaltene were prepared to explore the effect of the MACs on paraffin crystallization and asphaltene dispersion, respectively. We found that MACs reduced the yield stress, changed the size and shape of the paraffin crystals, and obstructed the paraffin crystallization for both model oils and extraheavy Liaohe oils as observed by rheology, polarizing light microscopy, X‐ray diffraction, and differential scanning calorimetry. The MACs seemed to be an ideal candidate for improving the flowability of Liaohe extraheavy oils. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40082.     

含蜡原油管道清、防结蜡技术

在管道输送含蜡原油的过程中,由于原油的物性,即原油的内在因素,和外界环境因素的影响,输送过程中会产生操作上的问题,有时会严重影响生产的进行。本文针对目前我国原油输送管道所存在的含蜡问题,分析含蜡原油管线结蜡机理和影响因素,提出了常用于输油管道的清防蜡化学药剂。     

HPAM对孤岛原油及沥青质油水界面特性影响的研究

用界面张力仪、表面粘弹性仪和Zeta电位仪测定了孤岛原油及沥青质模型油的界面特性,研究了部分水解聚丙烯酰胺(HPAM)浓度对这些界面特性的影响。结果表明,加入HPAM会使孤岛原油模型油及沥青质模型油与模拟水间的界面张力上升,但随着HPAM浓度增加,界面张力基本保持不变。当水溶液中HPAM的质量浓度大于5.0mg/L时,孤岛原油模型油及沥青质模型油与模拟水的界面剪切粘度随HPAM浓度增大明显增加,随着体系老化时间从1h增加到12h,其界面剪切粘度也有所增加。另外,HPAM还使得原油及沥青质模型油与模拟水体系所形成的O/W型乳状液的油珠表面Zeta电位变大。     

Synthesis and characterization of block comb‐like copolymers P(A‐MPEO)‐block‐PSt

Amphiphilic block comb‐shaped copolymers, poly[poly(ethylene oxide) methyl ether acrylate]‐block‐polystyrene [P(A‐MPEO)‐block‐PSt] with PSt as a handle, were successfully synthesized via a macromonomer technique. The reaction of MPEO with acryloyl chloride yielded a macromonomer, A‐MPEO. The macroinitiator PSt capped with the dithiobenzoate group (PSt‐SC(S)Ph) was prepared by reversible addition–fragmentation transfer (RAFT) polymerization of styrene in the presence of benzyl dithiobenzoate, and used as macroinitiator in the controlled radical block copolymerization of A‐MPEO at room temperature under ⁶⁰Co irradiation. After the unreacted macromonomer A‐MPEO had been removed by washing with hot saturated saline water, block comb‐shaped copolymers were obtained. Their structure was characterized by ¹H NMR spectroscopy and gel permeation chromatography. The phase transition and self‐assembling behaviour were investigated by atomic force microscope and differential scanning calorimetry. Copyright © 2004 Society of Chemical Industry     

Synthesis of comb‐type copolymers with various pendants and their effect on the complex rheological behaviors of waxy oils

To improve the flowability of waxy crude oil containing a high concentration of asphaltenes (AS), novel comb‐type copolymers of poly(maleic acid polyethylene glycol ester‐co‐α‐octadecene) (PMAC) and poly(maleic acid aniline amide‐co‐α‐octadecene) (AMAC) with various grafting ratios (R_g) of PEG/aniline to maleic anhydride are synthesized. Model oils containing wax mixtures and AS are prepared to explore the effect of asphaltene concentration and the copolymers on the yield stress. The influence of the copolymers on the wax appearance temperature (WAT) of Liaohe high waxy oil is examined by rheological and microscopic methods. Experimental flow curves of shear stress as a function of shear rate are fitted following the Casson model to interpret the rheological properties of gelled waxy crude oil in the presence of AMACs, PMACs, and MAC. Compared with MAC, PMACs, and AMACs are more efficient in reducing the yield stress of both model oil and crude oil, which indicates a better flowability. It is found that PMAC1.0 and AMAC1.0 with a medium R_g can balance the interaction of copolymers with waxes and AS and reduce the yield stress much more than others. Between them, AMAC1.0 that possesses aromatic pendants is better than PMAC1.0, which only has polar pendants. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41660.     

Non-isothermal programmed pyrolysis studies of oil sand bitumens and bitumen fractions: 1. Athabasca asphaltene

Characteristic pyrolysis thermograms for 12 gases have been obtained for Athabasca asphaltene, using a combination of non-isothermal, programmed pyrolysis (ambient to 1200 K at 3 K min^?1) and gas chromatography. Such thermograms provide information for the characterization of asphaltenes in the form of gas yields, specific rates and Arrhenius kinetic parameters. All thermograms comprised more than one peak. These peaks lie in distinct temperature zones and are associated with primary and secondary cracking and coking reactions. Useful insights into the structure of Athabasca asphaltene and, indirectly, the composition of its pyrolytic cokes have been obtained. The present results provide a body of useful reference material which may be useful for monitoring processes, which may chemically modify the asphaltene fraction of bitumens and heavy oils, and for comparative studies of asphaltenes from a variety of sources.     

沥青质引发的蜡油体系结蜡层分层现象及分层规律

利用自主研发的Couette结蜡装置,对蜡含量相同的油样1(不含沥青质)和油样2[含0.75%(质量分数)沥青质]进行结蜡实验,并研究其结蜡层的分层现象和分层规律。通过对油样1和油样2结蜡表层和底层的宏观形貌、DSC放热、析蜡量、蜡晶微观形貌的分析发现:油样1结蜡层无明显分层现象,而油样2结蜡层分层现象明显,沥青质的加入导致了结蜡层的分层。与结蜡表层相比,油样2结蜡底层的析蜡点、蜡含量与沥青质含量显著升高,蜡晶形貌发展为致密的类球状大蜡晶。油样2结蜡表层沉积量随壁温的升高、油壁温差和转速的增大而减小;结蜡底层沉积量随壁温升高而减小,随油壁温差和转速的增大而增大;总的蜡沉积量随壁温的升高和转速的增大而减小,随油壁温差的增大先增大后减小。     

不同结构星型聚合物防蜡剂的防蜡率研究

用季戊四醇、丙三醇、二元酸、二元醇、一元酸和一元醇等合成了一系列不同支链数目、不同支链长度和不同极性基团比例的星型结构聚合物防蜡剂,评价了不同结构防蜡剂的防蜡率。结果表明:星型结构聚合物防蜡剂的支链数目为4、极性基团比例为27.9%、相对分子质量为7500、加量为2000×10-6时,在煤油石蜡溶液中的防蜡率达40.5%。     

Molecular and submolecular scale effects of comb‐copolymers on tri‐calcium silicate reactivity: Toward molecular design

The impact of organic compounds on the processing and reactivity of inorganic materials has been a source of inspiration for materials scientists for decades and continues to trigger novel and innovative applications in a broad range of disciplines. However, molecular design of such compounds to reach targeted properties remains challenging, particularly for reactive and multicomponent systems. This outstanding challenge is met here by combining a model cement, hosting different coupled reactions of dissolution, nucleation and growth, together with comb‐copolymers that offer large and well‐controlled variations of their molecular architecture. We show that silicate reactivity is affected by a combination of molecular and submolecular scale effects of these polymers. The first can be described by scaling laws from polymer physics, whereas the second involves specific chemical interactions. In particular, the ability of these polymers to hinder dissolution appears to be crucial, something for which strong experimental evidence is provided.     

微生物降解稠油中沥青质的研究进展

稠油因黏度高、流动性差,存在开采难度大、开发成本高的问题。沥青质等重组分含量高是造成稠油高黏度的主要原因。微生物通过降解重组分可降低稠油的平均分子量,从而降低稠油黏度。本文从沥青质的结构与组成出发,阐述了微生物对沥青质的降解机理,总结了近年来国内外最新研究进展,指出了目前微生物降解沥青质研究与应用所面临的挑战,并对其发展趋势做出了展望。微生物对沥青质的降解主要是通过将多环芳烃进行开环降解、将长链正构烷烃降解为短链、将杂环化合物进行开环除去杂原子三个方面。但因沥青质的分子量较大且组成有着不确定性,所筛选的微生物是否能够高效地降解储层中原油所含沥青质仍需进一步探究,因此高效沥青质降解菌株的筛选和利用基因工程等技术手段改造菌株应是未来工作的研究重点。此外,通过菌株的复配,利用菌株间的协同效应也可以达到更为高效降解沥青质的目的。     

石蜡油在全钢载重子午线轮胎气密层中的应用

研究石蜡油在全钢载重子午线轮胎气密层中的应用,并与使用芳烃油的胶料进行性能对比.结果表明,全钢载重子午线轮胎气密层胶料中采用石蜡油替代芳烃油,胶料性能变化不大,压型工序复合时过渡层与气密层胶料能很好粘合,对胶料气密性无重大影响.成品轮胎耐久性能超过国家标准,速度性能达到企业要求.     

聚乙烯/石蜡油共混体系动态流变行为和相容性

将分子量相差较大的两种聚乙烯(PE)分别与石蜡油(LP)组成共混体系,通过旋转流变仪、偏光显微镜(PLM)、差示扫描量热仪(DSC)和扫描电子显微镜(SEM)研究了温度和LP含量对共混体系动态流变行为的影响,并对两相共混体系的相容性及微孔结构进行了表征.结果表明,随着温度的升高和LP含量的增加,PE/LP共混体系的储能...     

含蜡原油管道结蜡机理及清蜡技术研究

在管道输送含蜡原油的过程中,由于原油的物性,即原油的内在因素,和外界环境因素的影响,输送过程中会产生操作上的问题,有时会严重影响生产的进行。针对目前我国原油输送管道所存在的含蜡问题,分析含蜡原油管线结蜡机理和影响因素,提出了常用于输油管道的清防蜡化学药剂。     

金属加工油专用氯化石蜡的应用与市场前景

分析了氯化石蜡在金属加工油方面的应用情况和市场前景。     

Molecular mobility in comb‐like copolymethacrylates with chalcone‐containing side‐chains

The molecular mobility of comb‐like copolymers of amyl methacrylate with N‐methacryloyl‐(4‐amino‐4′‐bromochalcone) with various concentrations (20, 30, 40, 50 and 60 mol%) of chalcone‐containing comonomer was studied using dielectric spectroscopy. It was found that chalcone chromophores participate in two forms of molecular mobility: cooperative motion in the rubbery state (δ‐relaxation) and local motion in the glassy state (β‐relaxation). In addition, α‐, β₁‐ and γ‐processes, being related to cooperative segmental mobility, to local motion of ester groups adjacent to the backbone and to local motion of terminal side‐groups, respectively, were evident. The molecular mobility of the β₁‐, β‐ and γ‐processes changed slightly with the concentration of chromophore groups. For the δ‐ and α‐processes, the glass transition temperatures, T_δ and T_g, increased with the molar fraction of chalcone groups, the difference between them remaining nearly constant (ca 55 °C). The T_δ values obtained should be considered as optimal temperatures for the corona‐poling of the chromophore‐containing polymers for the preparation of second‐order nonlinear optical polymer films with non‐centrosymmetric arrangement of chromophore groups. Copyright © 2011 Society of Chemical Industry     

石蜡填充型丙烯酸酯吸油性树脂的合成及性能

以过氧化苯甲酰(BPO)为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,甲基丙烯酸丁酯为单体,聚乙烯醇为分散剂,石蜡为填充剂,采用悬浮聚合法合成了填充型吸油树脂。通过对产物的吸油率、保油率和脱油性能的测试研究了各反应物用量对树脂性能的影响,用正交实验法确定了最佳工艺。结果表明:石蜡、引发剂、交联剂和分散剂的质量分数分别为1.0%、0.4%、1.6%和1.0%(基于单体质量),反应温度80℃,反应时间5 h,水与单体质量比8∶1时,合成的树脂在48 h饱和吸油率为23.80 g/g。与未添加填充剂的吸油树脂比较,石蜡填充型丙烯酸酯吸油性树脂的吸油率、保油率提高,脱油性能更好,但凝胶分率变化不大。     

高蜡原油化学清蜡减阻剂的组成及性能

通过对多种油基清蜡剂进行溶蜡、减阻性能研究,筛选、复配较优化清蜡剂组成,分析了温度、溶剂种类等因素对溶蜡效果的影响。结果发现石蜡的溶解量与溶剂的体积相关性不大,石蜡量应控制在溶剂的饱和溶蜡量以内,此外溶蜡的时间不宜过长,理想时间选择40～100 min之间。既在10 mL溶剂中溶解0.5 g石蜡比较符合实际情况,且加热状态的温度选择在35 ℃左右较为适宜。同时发现,表面活性剂对石蜡有增溶作用,只有选择HLB值在13～16范围内的表面活性剂才能有利于提高溶剂溶蜡的速度。采用差示扫描量热法（DSC）考察了石蜡的热性能和相变性质。结果表明,温度因素的影响特别显著,且石蜡熔点越高,其相变所需要的能量也越大,当石蜡的熔点44.30 ℃时,相变能为29.28 J/g。     

Fabrication of surface‐modified CdSe quantum dots by self‐assembly of a functionalizable comb polymer

A facile approach is proposed for the fabrication of surface‐modified CdSe quantum dots (QDs) with compatibility with various media and better dispersibility by self‐assembly of a functionalizable comb polymer. The comb polymer was prepared from the reaction between the acyl chloride groups in poly(acryloyl chloride) and the hydroxyl groups in 1‐octadecanol. With the combination of the compatibility and entanglement of the aliphatic chain in 1‐octadecanol and similar aliphatic chain in oleic acid ligand of QDs, the comb polymer could cap on the QDs and thus endow them with functional groups. The structure of such a polymer was investigated using Fourier transform infrared spectroscopy. According to the reactivity of remaining acyl chloride groups in the comb polymer, the polymer ligands could be tailored to be various structures, and then lipophilic, hydrophilic and functional QDs were obtained. The fluorescence properties of the surface‐modified QDs were investigated, and the morphologies and dispersions of different kinds of surface‐modified QDs were characterized using transmission electron microscopy. Finally, homogeneous and stable dispersions of QDs in various media could be realized by adjusting the structure of the comb polymer. Copyright © 2010 Society of Chemical Industry     

Synthesis and evaluation of comb‐type copolymers prepared via atom transfer radical polymerization as possible cold flow improvers in GTL diesel fuels

Statistical comb‐type copolymers of styrene (Sty) and stearyl methacrylate (C18 MA) with varying [styrene]:[C18MA] ratios were synthesized by a controlled/living radical polymerization technique called atom transfer radical polymerization. The polymeric materials were evaluated in selected SASOL Fischer Tropsch gas‐to‐liquid diesels as possible cold flow improvers. Crystallization studies revealed that as the styrene content of the copolymer increased, a crystal growth inhibition mechanism was exhibited. With an increase in styrene content of the copolymer, differential scanning calorimetry and the cloud filter plugging point (CFPP) revealed a delay in onset of crystallization and lowered CFPP, respectively, whereas low‐temperature microscopy indicated modifications and size reduction of wax crystals. However, there appeared to be a styrene content, beyond which the additive's efficiency decreased. Homopolymer and copolymers with the highest styrene content led to long unfavorable needle‐shaped crystals. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012