Study on monomer reactivity ratios of acrylonitrile/itaconic acid in aqueous deposited copolymerization system initiated by ammonium persulfate

A single water-soluble initiator-ammonium persulfate (APS), not containing alkali metal ions, was first utilized to initiate copolymerization of acrylonitrile (AN)/itaconic acid (IA) in aqueous deposited copolymerization system. Monomer reactivity ratios of this polymerization system were investigated using element analysis method and Q–e schemes. It was found that the monomer reactivity ratios of AN/IA calculated from Q–e schemes are 0.505 (r _AN) and 1.928 (r _IA), while the monomer reactivity ratios of AN/IA in aqueous deposited copolymerization system at 60 °C are 0.64 (r _AN) and 1.37 (r _IA) calculated from Kelen–Tüdõs method, 0.61 (r _AN) and 1.47 (r _IA) from Fineman–Ross method. The three pairs of monomer reactivity ratios are in good agreement. With the increase of the polymerization temperature, the monomer reactivity ratios of AN and IA approach to unity, indicating that the aqueous deposited copolymerization of AN/IA has a tendency to ideal copolymerization. At lower polymerization conversion, the monomer reactivity ratios of AN and IA have hardly any changes. When the polymerization conversion is more than 5%, the monomer reactivity ratio of AN increases, while that of IA decreases.     

Control of local friction of metal/ceramic contacts in aqueous solutions with an electrochemical method

Ball-on-plate sliding friction experiments were designed and performed to show the possibility of local friction control by electrochemical methods. By partitioning a metal plate into charged and uncharged zones, the friction coefficient in these zones can be differential when an external voltage is applied during rubbing. It is also possible to achieve differential friction at different locations of contact by arranging the position of the auxiliary electrode on which the range of electrochemical effects on friction depends. The morphological differences in the worn surfaces between the different zones are given, together with a discussion on the principles of the electrochemical control of friction.     

水溶性酚醛树脂作为水基聚合物凝胶交联剂的研究

用由苯酚和甲醛合成的水溶性酚醛树脂作两性离子聚丙烯酰胺的交联剂,得到了性能良好的水基凝胶并成功地应用于沈阳油田的深部调剖。本文报道了水溶性酚醛树脂的两步催化合成工艺,确定了原料配比、反应温度、反应时间等合成条件,考察了水溶性酚醛树脂的稳定性,简要介绍了形成的凝胶物性以及调剖效果。     

聚丙烯酰胺浓度测量方法综述

本文综述了１１类测量ＨＰＡＭ浓度的方法，讨论了每一种方法的原理、特点、干扰因素和应用范围。     

MCB系列微胶囊破胶剂的性能

为解决水平井分段压裂过程中前段压裂液快速破胶的问题,以过硫酸铵为破胶剂,采用乳液聚合法合成2种具有不同囊衣结构的微胶囊破胶剂。测定了微胶囊破胶剂的有效含量、包埋率、释放速率及延迟破胶效果。实验结果表明,MCB-1、MCB-2两种微胶囊破胶剂的有效含量分别为38.56%和39.69%,包埋率分别为83.85%和85.89%。与普通市售包蜡胶囊破胶剂相比,该微胶囊破胶剂的释放速率较慢。延迟破胶实验表明,微胶囊破胶剂可以在4h内保持压裂液的黏度缓慢降低,最终破胶后压裂液的黏度小于10mPa²s,显示出良好的延迟破胶性能,且对地层渗透率的伤害率小于12%。      

克拉玛依原油中活性组分的分离与分析

用碱醇液萃取法从克拉玛依原油中分离出了界面活性组分并进行了元素分析,通过硅胶柱层析按极性大小将该活性组分分成了５个级分,对５个级分进行了红外光谱分析,发现其主要成分是石油酸。用旋转滴法测定了该活性组分及其５个级分与碱水间的界面张力,结果表明的含氮化合物及石油酸具有较高的界面活性,可以使原油与ＮａＯＨ水溶液的界面张力降至１０＾－２ｍＮ／ｍ。     

延缓交联深部调剖剂YHT的成胶性

本文介绍了一种延缓交联的聚丙烯酰胺HPAM水基凝胶 ,研究了HPAM、缓释交联剂、促进剂的浓度及 pH值对凝胶形成时间、凝胶粘度的影响。成胶溶液用大庆油田聚合物驱配液水配制 ,成胶时间可调 ,凝胶强度高 ,与大庆油田目的油层配伍性好 ,残余阻力系数高 ,适用于大庆油田聚合物驱前注入井的深部调剖     

原油碱水乳化活性组分研究

对河南油田三种原油中的有机酸和非酸含氧化合物进行了分离鉴定并研究了它们在碱水乳化中的作用。有机酸是引起各原油碱水乳化的活性物质，非酸含氧化合物本身无碱水乳化活性，但对有机酸的乳化活性有协同作用。     

逆乳化凝胶润滑封堵剂XZ-RF

研制出了一种逆乳化凝胶润滑封堵剂XZ-RF,分析了其作用机理,对其润滑性和封堵性进行了评价。实验结果表明,XZ-RF具有很好的润滑能力,1%的加量即可将膨润土浆摩阻系数降低60%,当XZ-RF加量为3%时,可将膨润土浆摩阻系数降低80%以上,且XZ-RF在聚合物钻井液能表现出良好的润滑性;XZ-RF具有好的抗温、抗盐封堵能力,可将膨润土加重浆160℃高温高压滤失量降低65.8%,将欠饱和盐水加重浆120℃高温高压滤失量降低86.8%。XZ-RF在新疆油田2口预探井进行了现场应用,均取得了较好的效果,而且该产品无荧光,具有更大的应用范围。      

植物胶压裂液用有机硼交联剂SD2-2

本文简介了液态有机硼交联剂ＳＤ２２的合成和物理特性，发表了用ＳＤ２２交联的４类６种植物胶（改性魔芋胶、改性田菁胶、改性龙胶、３种改性瓜尔胶）压裂液的配方和８０℃粘时数据。这些压裂液粘度适中，保持高粘度时间长，１０—１２ｈ可彻底破胶。从这些配方中推荐了ＣＴ９１／ＳＤ２２压裂液（用于７０—９０℃井温），详尽研究了推荐配方压裂液的各项性能。通过４个井例，简介了ＳＤ２２交联羟丙基瓜尔胶、羟丙基田菁胶压裂液在新疆、四川、吉林一些地区５０余井次现场应用的良好效果