干水法制备核壳聚合物微球及其性能评价

以丙烯酰胺、2-丙烯酰胺基-2-甲基丙磺酸为单体，N,N’-亚甲基双丙烯酰胺为交联剂，过硫酸铵和亚硫酸氢钠为引发剂，水为溶剂，疏水Si O₂为壳层原料，采用干水法制备干水微反应器，将其干燥后即得核壳聚合物微球(PMS@SiO₂)。考察了SiO₂疏水性、疏水Si O₂与水相质量比、搅拌速度和搅拌时间对形成稳定干水微反应器的影响，通过正交实验对PMS@SiO₂的制备条件进行了优化。采用FTIR、TGA、激光粒度仪、SEM和TEM对样品进行了表征，评价了PMS@SiO₂吸水膨胀性能和调驱性能。结果表明，PMS@SiO₂的最佳制备条件为m(SiO₂-R812S)∶m(水相)=1∶10，搅拌速度12000 r/min，搅拌时间120 s，交联剂用量0.10%(以单体总质量为基准，下同)，引发剂用量0.15%，反应温度50℃，反应时间4 h。与常规聚合物微球PMS相比，PMS@SiO₂在90℃环境中水化...     

核壳聚合物微球的制备方法及应用

综述了近年来核壳结构聚合物微球制备方面的研究进展,介绍了乳液法、自组装法、模板法、沉积法等主要制备方法,阐述了各种方法所涉及的机理.介绍了目前核壳聚合物微球的应用现状,如制备中空微球、用磁性核壳微球提高医学诊断的准确率及作为填料改性聚合物等,表明核壳微球有着广阔而重要的应用前景.     

一种调驱用聚合物微球的制备与性能评价

储层非均质性与注水剖面不均匀性限制了油藏水驱后的采收率,聚合物微球具备尺寸可控、注入性能好、封堵效率高等优点在油田调驱中取得了良好的应用效果。以丙烯酰胺与甲基丙烯酰氧乙基三甲基氯化铵为单体制备了PAD聚合物微球,通过红外光谱与扫描电镜表征了微观结构与表观形态,研究了模拟地层环境下的调驱性能。实验结果表明,采用反向乳液法制备的微球形状均匀、尺寸均一、球形度好。模拟地层条件下,PAD聚合物微球在32 h后体积膨胀9倍,表现出良好的水化膨胀性能与耐温耐盐能力。调驱实验证明PAD聚合物微球对高中低三种渗透率岩心均有良好的封堵效果,具备良好的应用潜能。     

聚合物微球性能及调驱机理研究

聚合物微球具有膨胀性好、耐温耐盐性、抗剪切性以及延迟膨胀等特性,能很好的应用于深部储层调驱技术。它的初始粒径小,能够随注入液进入地层深部进而水化膨胀至最大体积,对高渗透大孔道产生有效封堵的作用,从而使流体发生微观改向。随着注入压力的增加,聚合物微球作为一种弹性球体会产生变形,从而继续运移直至下一次封堵,表现出了逐级深部调驱的特性。     

新型聚合物微球调剖体系的研究及应用

油井开发中后期,油井含水上升,油水井之间的大孔道,造成注入水的无效循环,水驱效率降低,导致最终采收率降低,调剖堵水是提高水驱效率的必要手段.目前常用的聚丙烯酰胺可动凝胶体系存在施工不方便、成胶时间不易控制等问题,本文研究了具有核壳双层结构的核壳类聚合物微球调剖体系,并利用室内实验对水化规律进行评价.通过理论分析与室内实验,研究了核壳类聚合物微球遇水膨胀与微球相互聚并产生封堵的过程.并在某油田实施新型聚合物微球体系深部调驱矿场试验,增油控水效果显著.该技术为水驱油田后期提高采收率提供了新的技术方法.     

一种交联核壳微球的合成及其结构与性能的研究

采用反相微乳液法,制备出用于调剖堵水的交联SiO_2/(PAM-PAA)核壳微球。对改性二氧化硅、核壳微球的化学结构及微球与孔隙的匹配关系做了研究。结果表明,二氧化硅成功被改性,二氧化硅的接枝率为1.1%;当核孔膜孔径大小为12μm及填砂管渗透率为0.92 D时,微球具有最佳的深部调剖效果。     

一种交联核壳微球的合成及其结构与性能的研究

采用反相微乳液法,制备出用于调剖堵水的交联SiO_2/(PAM-PAA)核壳微球。对改性二氧化硅、核壳微球的化学结构及微球与孔隙的匹配关系做了研究。结果表明,二氧化硅成功被改性,二氧化硅的接枝率为1.1%;当核孔膜孔径大小为12μm及填砂管渗透率为0.92 D时,微球具有最佳的深部调剖效果。     

碱溶胀法制备核壳中空微球研究进展

综述了碱溶胀法合成核壳中空微球的国内外研究进展,重点介绍了核壳中空结构的合成以及各种因素如聚合物组成,碱处理条件、乳化剂用量、单体瞬时转化率以及玻璃化温度对微球形态的影响。     

核壳结构聚合物/金属复合微球的合成及应用研究进展

核壳结构复合微球的制备可实现粒子性能的设计和优化,尤其是以聚合物微球为核、金属层为壳的半有机半无机结构球形材料,成为近年来导电微球领域的研究热点。本文综述了磁控溅射法、溶胶凝胶法、原位还原法、层层自组装法和紫外辐照法等核壳结构聚合物/金属复合微球的主要制备方法及各自的优缺点。介绍了该类微球在诸如各向异性导电膜（ACF）、污水处理、吸波材料和表面增强拉曼散射（SERS）等具体领域的应用情况,并对其今后的发展进行了展望。     

聚丙烯酰胺核壳结构活性微球的室内评价

聚丙烯酰胺活性微球广泛应用于油田深部调剖堵水领域,纳微米丙烯酰胺共聚物微球对提高原油采收率发挥越来越突出的重要作用。微球的化学组成、比例、结构等指标影响着微球的应用性能,而微球的形貌、粒径大小及其分布是影响封堵性能的重要因素。通过聚丙烯酰胺活性微球评价方法研究,初步建立微球评价体系,明确微球结构和性能的关系,能够为聚丙烯酰胺活性微球的性能改进、结构设计提供一定程度的指导。     

Preparation and properties of novel pH‐sensitive core−shell microspheres for enhanced oil recovery

A novel pH‐sensitive core?shell microsphere was synthesized by growing sodium acrylate as a shell on crosslinked polyacrylamide particles as the core by surface‐initiated atom transfer radical polymerization. The structures and characteristics of the microspheres were confirmed by Fourier transform infrared spectroscopy, ¹H NMR spectroscopy, SEM, transmission electron microscopy and AFM. The viscosity and size of the microspheres in response to changes in pH value were also investigated. As a kind of potential profile control and flooding agent, the performances of permeability reduction and enhanced oil recovery were studied in designed experiments. © 2017 Society of Chemical Industry     

聚合物微球-缔合聚合物复合体系的封堵性能研究

针对海上稠油油藏地质特征及提高采收率的具体要求,选择聚合物微球与缔合聚合物进行复配,通过填砂管封堵实验和人造岩心驱油实验,发现复合体系兼具深部调剖和增黏驱油的性能,封堵性能、液流改向能力和驱油效果均优于单纯聚合物溶液.说明微球和缔合聚合物之间产生较好协同作用,为改善聚合物驱效果提供了新的方法.     

聚合物微球-缔合聚合物复合体系的封堵性能研究

针对海上稠油油藏地质特征及提高采收率的具体要求,选择聚合物微球与缔合聚合物进行复配,通过填砂管封堵实验和人造岩心驱油实验,发现复合体系兼具深部调剖和增黏驱油的性能,封堵性能、液流改向能力和驱油效果均优于单纯聚合物溶液。说明微球和缔合聚合物之间产生较好协同作用,为改善聚合物驱效果提供了新的方法。     

Preparation and characterization of magnetic amphiphilic polymer microspheres

Magnetic amphiphilic polymer microspheres were prepared by copolymerization of styrene with poly(ethylene oxide) macromonomer (MPEO) in the presence of Fe₃O₄ magnetic fluid in ethanol/water medium. Magnetic microsphere size, size distribution, and surface morphology were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The structure of copolymer was determined by infrared spectroscopy. With increasing MPEO used in the polymerization, the resulting microsphere size decreased. Magnetic amphiphilic polymer microspheres containing 0.02–0.2 mmol/g hydroxyl groups could be prepared by using different MPEO concentration. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1847–1851, 2001     

Preparation of polymer/silica/polymer tri-layer hybrid materials and the corresponding hollow polymer microspheres with movable cores

Tri-layer poly(methacrylic acid-co-ethyleneglycol dimethacrylate)/silica/poly(ethyleneglycol dimethacrylate) (P(MAA-co-EGDMA)/SiO₂/PEGDMA) and P(MAA-co-EGDMA)/SiO₂/polydivinylbenzene hybrid microspheres were prepared by distillation precipitation polymerization of ethyleneglycol dimethacrylate (EGDMA) and divinylbenzene (DVB) in the presence of 3-(methacryloxy)propyl trimethoxysilane (MPS)-modified P(MAA-co-EGDMA)/SiO₂ microspheres as the seeds. The polymerization of EGDMA and DVB was performed in neat acetonitrile with 2,2′-azobisisobutyronitrile (AIBN) as initiator to coat the MPS-modified P(MAA-co-EGDMA)/SiO₂ seeds through the capture of EGDMA and DVB oligomer radicals with the aid of vinyl groups on the surface of modified seeds in the absence of any stabilizer or surfactant. Monodisperse P(MAA-co-EGDMA)/SiO₂ core-shell microspheres were synthesized by coating of a layer of silica onto P(MAA-co-EGDMA) microspheres via a sol-gel process, which were further grafted by MPS incorporating the reactive vinyl groups onto the surface to be used as the seeds for the construction of hybrid microspheres with tri-layer structure. Hollow poly(ethyleneglycol dimethacrylate) (PEGDMA) and poly(divinylbenzene) (PDVB) microspheres with movable P(MAA-co-EGDMA) core were subsequently developed after the selective etching of the silica mid-layer from the tri-layer hybrid microspheres in hydrofluoric acid. The morphology and structure of the tri-layer polymer hybrids and the corresponding hollow polymer microspheres with movable P(MAA-co-EGDMA) core were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectra and X-ray photoelectron spectroscopy (XPS).     

高分子大孔微球的制备和结构控制

高分子大孔微球的形成和结构调控是一个复杂的过程,特别对于孔径超过100 nm的超大孔微球而言,无法通过常规的制孔剂与聚合物之间的相分离得到。针对生化工程对于超大孔微球的重要需求,发展了反胶团溶胀法和复乳法,实现了孔径在百纳米级以上的控制。研究了微球结构对于应用效果的影响。超大孔微球用于生物大分子的分离纯化,显示出高载量、高活性回收率、高纯化倍数的特点。超大孔微球固定化酶在酶的热稳定性、储存稳定性、重复使用性能等方面具有显著的优势。微球的结构有效控制是在不同领域获得成功应用的保障。     

一步聚合法合成多孔磁性高分子微球及其机理研究

在羰基铁粉存在下,将苯乙烯与甲基丙烯酸甲酯通过悬浮聚合方法制备了表面多孔的磁性高分子微球。采用SEM、FTIR及XRD等对样品进行了表征。研究表明,聚合形成的磁性高分子微球表面粘附着40 nm左右的聚合物粒子,这些粒子之间形成孔隙。具有两亲性和可接枝聚合的明胶分子促成了单体在羰基铁粉表面引发并聚合。     

油田调驱用聚合微球的构效关系及应用进展

聚合微球是一种基于聚丙烯酰胺的可吸水溶胀凝胶树脂,在油田调驱中取得了良好的降水增油效果.随着开采重点逐渐向低渗、中低渗高温油藏偏移,聚合微球的粒径尺寸、缓膨性能以及耐温抗盐抗剪切性能成为重要的研究课题.该文对近年来不同聚合微球的结构特点和构效关系进行综述,总结了不同聚合微球所适用的油藏条件,分析了聚合微球粒径和溶胀性能的影响因素,探讨了聚合微球的调驱机理,并对聚合微球的研究方向进行了展望.针对聚合微球关于纳米尺度的报道较少,高温下溶胀速度快,驱油机理单一等问题,需要加深对聚合微球溶胀机理和黏弹机理的研究,优化反相微乳液法合成条件,研发具有核壳结构的纳米聚合微球,并与其他化学试剂协同调驱,从而拓宽聚合微球在低渗、中低渗高温油藏的应用领域.     

Preparation and structural analysis of a comb-like polymer through functional monomer design

Partially hydrolyzed polyacrylamide (HPAM) is the most extensively used polymer for enhanced oil recovery due to its accessibility and low cost. However, HPAM shows inadequacies in high mineralization and high-temperature reservoirs. To solve this problem, a comb-like polymer with superior salt-resistance and stability named CHPAM was prepared via direct free-radical copolymerization of acrylamide (AM) and acrylic acid (AA) with the self-designed monomer (Acryloyl-MPEG-1000). The chemical structures of CHPAM and monomers were characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). Static light scattering (SLS) was adopted to measure the molecular weights of CHPAM and HPAM. The solution properties of CHPAM and HPAM were comparatively studied. It was found that CHPAM showed better thermal-salt stability and salt-resistance than HPAM, especially in Ca²⁺ solution. This work paves a new way for the preparation of novel polymers.