Initiator‐fragment incorporation radical polymerization of ethylene glycol dimethacrylate in the presence of 1,1‐diphenylethylene: synthesis and characterization of soluble hyperbranched polymer nanoparticles

The polymerization of ethylene glycol dimethacrylate (EGDMA) as crosslinker was carried out at 70 and 80 °C in benzene using dimethyl 2,2′‐azobisisobutyrate (MAIB) as initiator at concentrations as high as 0.50–0.70 mol l^?1 in the presence of 1,1‐diphenylethylene (DPE), where the concentrations of EGDMA and DPE were 0.50–0.70 and 0.25–0.50 mol l^?1, respectively. The polymerization proceeded homogeneously, without gelation, to give soluble polymers. The yield and molecular weight of the resulting polymers increased with time. The homogeneous polymerization system involved ESR‐observable DPE‐derived radicals of considerably high concentration (3.6–5.3 × 10^?5 mol l^?1). The methoxycarbonylpropyl groups as MAIB‐fragments were incorporated as a main constituent (35–50 mol%) into the polymers (initiator‐fragment incorporation radical polymerization). The polymers also contained DPE units (15 mol%) and EGDMA units with double bonds (10–25 mol%) and without double bonds (20 mol%). Results from gel permeation chromatography (GPC)–multiangle laser light scattering (MALLS), transmission electron microscopy (TEM) and viscometric measurements revealed that the individual polymer molecules were formed as hyperbranched nanoparticles. Copyright © 2004 Society of Chemical Industry     

Immobilisation of β-galactosidase onto gelatin by glutaraldehyde and chromium(III) acetate

β-Galactosidase (EC 3.2.1.23) was immobilised onto a gelatin carrier system by crosslinking. Glutaraldehyde and chromium(III) acetate were used as crosslinking agents. The effect of pH on enzyme activity, kinetic parameters and reusability of the immobilised enzyme were investigated. To obtain a better relative activity, a method was developed and further modified to increase the surface area of the support system by using polyacrylamide. Relative activity enhancement of 68% was achieved in the gelatin–glutaraldehyde system.     

聚氧化乙烯胶凝剂的应用及增稠性能评价

以聚氧化乙烯为胶凝剂，20％盐酸为溶剂，以及其他助剂，制得胶凝酸体系。考察了除氧剂、交联剂及加量对胶凝酸体系粘度的影响，结果表明，聚氧化乙烯胶凝剂与其他添加剂具有良好的配伍性，具有良好的增稠效果。确定了可用于高温酸化的胶凝酸体系配方：聚氧化乙烯胶凝剂加量（质量分数，下同）为0．8％，除氧剂为0．1％Na2SO3＋0．02％MnSO4，苯酚交联剂加量为0．1％，其余为20％盐酸。     

水基压裂液高温延缓型有机硼锆交联剂CZB-03的制备

报道了水基压裂液用低伤害、耐温、延缓型有机硼锆交联剂CZB-03的制备。在交联比100：0．4、NaCl加量O．04％条件下，以HPG压裂液交联时间和冻胶耐温温度为指标，考察了合成工艺条件，得到最佳工艺如下：氧氯化锆在质量比为1：1．25 3．75的水 异丙醇(溶剂)中与质量比为1：1．25 0．00625的多元醇PA 多羟基羧酸钠PH(复合多羟基络合剂)在温度为50℃、pH=2条件下反应4h，得到有机锆交联剂OZ-1，加入0．4％吸附抑制剂ZYCS，再与早先研制的有机硼交联剂OB-200按质量比1：1复配，得到有机硼锆交联剂CZB-03，交联时间约180 s,耐温温度高于160℃。图5表1参3。     

高温交联剂合成工艺研究

本文研究高温交联剂有机硼和有机锆的合成工艺。分别进行了以硼砂和硼酸为主要原料合成有机硼的试验研究。确定以硼砂为原料的合成路线最佳工艺条件为加料顺序C,反应温度50~55℃,反应时间30min;以硼酸为原料的合成路线最佳工艺条件为反应温度90~95℃,反应时间30 min。通过比较发现,硼酸为原料合成的有机硼的冻胶性能更为优异。合成有机锆最佳工艺条件为氧氯化锆用量3%,反应时间20 min。     

碱减量涤纶织物的明胶处理分析

利用明胶蛋白高分子溶液涂覆涤纶织物,把涤纶织物的高强度、高弹性与明胶蛋白等天然高分子的人体亲和性、舒适性进行有机结合,制成功能性涤纶织物,通过正交试验确定明胶处理的最优工艺为:明胶质量浓度为2 g/L,戊二醛质量浓度为2 g/L,温度为80℃,时间为40 min。     

复合凝胶堵剂的研制及应用

简要介绍了复合凝胶堵剂的制备方法.考察了凝胶含量、凝胶体系溶液pH、溶液温度、地层水矿化度对成胶速度和成胶黏度的影响.结果表明,凝胶含量在0.8％ ～ 2.0％,溶液pH 7.0 ～9.0,溶液温度65℃,地层水矿化度达20 000 mg/L条件下,凝胶溶液具有很强的成胶能力,并且成胶速度快,成胶黏度高.岩心封堵模拟实验结果表明,该凝胶堵剂封堵率达96.7％,高渗分流率由堵前82％下降到10％,低渗分流率由堵前18％上升到90％,有效封堵窜流通道,启动低渗通道.现场应用效果明显,压力比措施前上升4.5 MPa,增油量达569.1 t,投入产出比为1∶3.36.     

酸性有机钛交联剂的合成及其在压裂液中的应用

以钛酸丁酯为主剂,多元醇为络合剂合成了一种酸性有机钛交联剂,并以部分水解聚丙烯酰胺作为稠化剂,制备了部分水解聚丙烯酰胺压裂液。研究了交联剂中钛酸丁酯的质量分数,丙三醇与乳酸的质量比以及pH对冻胶交联延时、黏度的影响,得到较佳的合成条件。考察了质量分数为0.5%的部分水解聚丙烯酰胺,m（HPAM）：m（有机钛）=100:0.5时,有机钛/部分水解聚丙烯酰胺压裂液的性能,交联延时300s;耐温性能优异,在95℃,170s-1的条件下连续剪切90min,黏度保持在50mPa.s以上,体系耐温耐剪切性能良好;由线性黏弹性范围内动态频率扫描结果可知,G’>G”,是典型的黏弹性流体;常温下,V（压裂液）：V（石英砂）=100:30时,沉降速度0.025mm/s;破胶后,破胶液黏度低于5.0mPa.s且残渣量较低,对储层伤害小。     

一种新型水基压裂液酸性交联剂的制备

采用无机锆盐为原料,制备了一种酸性压裂液用交联剂。所合成产物具有低伤害、耐温、延缓交联时间等特点。经过实验,得到最佳反应条件为反应介质是异丙醇的水溶液,m(氧氯化锆)∶m(H2O)∶m(异丙醇)=1∶1.25∶2.5,m(葡萄糖酸钠)∶m(氧氯化锆)∶m(丙三醇)=1∶16∶20,反应温度50～55℃,pH=2,反应时间4h。通过实验研究,由所合成交联剂LY-2与羟丙基瓜尔胶交联得到的压裂液具有良好的性质,交联时间120s,冻胶黏度可以达到524mPa.s,耐温温度170℃,加入2%破胶剂(质量分数15%过硫酸铵)1h后,冻胶黏度可降至1.56mPa.s。     

水基压裂液有机硼交联剂的合成

为合成具有延缓交联性且抗温性较好的交联剂,实验采用控制变量法合成了性能较好的有机硼交联剂较佳工艺条件为:均以质量计,硼砂质量分数13%,配位体(葡萄糖与丙三醇质量比1∶4)25%,溶剂(丙三醇与水质量比1∶3)60%,催化剂2%,反应温度85℃,反应时间4⁴.5h。在此条件下,交联剂延迟交联时间可达280s,冻胶的抗温温度高达135℃,可以满足油田压裂液对交联剂的需求。