有机硅密封胶粘接聚烯烃材料的研究

研究了不同类型的有机硅密封胶对PE、PP材料的粘接性能,结果表明交联剂和界面因素是影响有机硅密封胶粘接性能的主要因素。根据研究结果设计合成自催化交联型有机硅密封胶和有机硅复合密封胶,并研究它们的性能。     

HPAM的相对分子量及电解质对LPS封堵性能的影响

采用微孔滤膜过滤法研究了在部分水解聚丙烯酰胺(HPAM)与交联剂柠檬酸铝(A lC it)的交联比确定的情况下,HPAM的相对分子量以及电解质对交联聚合物溶液(LPS)封堵性能的影响。结果表明,随着HPAM的相对分子质量的增大,HPAM与A lC it反应的时间增加,同时通过3μm微孔滤膜的过滤时间先增加后降低。LPS体系中电解质存在一个最佳的影响范围,当电解质(氯化钠、钙镁离子共同影响)的含量在5000~6000 mg/kg时,仍然可以得到稳定的胶态分散体系,且体系对多孔介质有较好的封堵效果。     

Controlled destruction of residual crosslinker in a silicone elastomer for drug delivery

In drug delivery systems that use silicone elastomers as a diffusion matrix for the active drug, it is common to crosslink the material by the hydrosilylation reaction. In this platinum‐catalyzed reaction, vinyl groups on a polymer add to the methyl siloxane hydride (MHS) groups on a low molecular mass crosslinker. With an excess of crosslinker, a fast curing is achieved and a fully crosslinked material is formed. Unreacted MHS groups were shown to remain in the elastomer after curing because of the excess crosslinker. In this work, a simple procedure was developed to eliminate the unreacted MHS groups from the final product. We found that storage of the product at +40°C and 75% relative humidity for a few weeks will effectively destroy the residual MHS groups in the elastomer. The effects of varying levels of humidity, oxygen, and temperature on this postcuring procedure were studied. The amount of MHS groups was measured with NMR and IR spectroscopy. We also found that the hardness of the material increased by approximately 25% as a consequence of this postcuring treatment. This increase is probably due to a secondary crosslinking reaction between MHS and silanol groups. Heat treatment at higher temperatures led to an even further increase in the hardness and compression modulus. Because no MHS groups remained in the elastomer when this heat treatment was started, it is apparent that another secondary crosslinking reaction is occurring, probably silanol condensation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2254–2264, 2002     

HPAM/有机锆交联体系压裂液的研究

制备了一种HPAM/有机锆交联体系酸性压裂液,分别讨论了HPAM和有机锆交联剂浓度对压裂液成胶性能的影响.结果表明,在25℃下,有机锆交联剂浓度为500mg·L-1,HPAM浓度为500mg·L-1,破胶剂过硫酸铵浓度为16g·L-1.耐矿化度为7 000 mg·L-1,耐温耐剪切测试表明,该压裂液体系在剪切速率170s-1条件下,连续剪切120min,耐温为95℃黏度在300mPa·s以上,表明该压裂液体系具有良好的耐温耐剪切性能.压裂液综合性能评价表明:压裂液体系悬砂性能好,破胶速度快、彻底,破胶液残渣含量低,对岩心伤害小.     

可水分散多异氰酸酯技术进展

可水分散多异氰酸酯作为双组分水基胶粘剂和涂料交联剂,具有使用时不会生成甲醛等有害物质的优点。简介制备方法,着重介绍国内外技术进展以及在织物整理、木材加工等方面的用途。     

Macromolecular crosslink of imidazole functionalized poly(vinyl alcohol) and brominated poly(phenylene oxide) for anion exchange membrane with enhanced alkaline stability and ionic conductivity

Anion exchange membranes (AEMs) are important energy conversion device for fuel cell applications, where the overall redox reaction happened. Both alkaline stability and ionic conductivity should be considered in the long-term use of fuel cells. In this work, imidazole functionalized polyvinyl alcohol was designed as the functional macromolecular crosslinking agent to fabricate crosslinked AEMs with brominated poly(phenylene oxide) matrix. Benefitting from the macromolecular crosslinked structure, the membranes displayed enhanced ionic conductivity and alkaline stability at elevated temperature. Moreover, membrane with ion exchange capacity of 1.54 mmol/g displayed ionic conductivity of 78.8 mS/cm at 80 °C, and the conductivity could maintain 75% of the initial value after immersion in 1 M NaOH solution at 80 °C for 1000 h. Moreover, a peak power density of 105 mW/cm² was achieved when the assembled single cell with c-91 was operated at 60 °C. These results indicated that the construction of macromolecular crosslinked AEMs have great potential in the practical application of anion exchange membranes fuel cells.     

Methacrylated calix[4]arene phosphonic acids as functionalized crosslinker for radical polymerization

We describe the synthesis of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐dioxypropylphosphonic acid‐26,28‐dimethacryloyloxy‐calix [4]arene and 5,11,17,23‐tetra‐tert‐butyl‐25‐oxypropylphosphonic acid‐27‐hydroxy‐26,28‐dimethacryloyloxy‐calix[4]arene starting from para‐tert‐butyl‐calix[4]arene. The complete reaction was proved by matrix‐assisted laser desorption ionization time of flight mass spectrometry and nuclear magnetic resonance spectroscopy. The influence of these compounds on the kinetics of the radical polymerization of methyl methacrylate was shown by dilatometry. Furthermore, the adhesive properties of dental adhesives containing these calix[4]arene derivatives were investigated. Copyright © 2012 Society of Chemical Industry     

延迟交联调剖技术概况

阐述了延迟交联调剖技术在提高原油采收率方面所起的重要作用,通过对国内外延迟交联调剖技术现状的综述,介绍了延迟交联技术、调剖剂的分类,以及延迟交联作用机理,提出应该进行更多的研究延迟交联技术。     

Covalently Immobilized Regenerable Immunoaffinity Layer with Orientation-Controlled Antibodies Based on Z-Domain Autodisplay

A regenerable immunoaffinity layer comprising covalently immobilized orientation-controlled antibodies was developed for use in a surface plasmon resonance (SPR) biosensor. For antibody orientation control, antibody-binding Z-domain-autodisplaying Escherichia coli (E. coli) cells and their outer membrane (OM) were utilized, and a disuccinimidyl crosslinker was employed for covalent antibody binding. To fabricate the regenerable immunoaffinity layer, capture antibodies were bound to autodisplayed Z-domains, and then treated with the crosslinker for chemical fixation to the Z-domains. Various crosslinkers, namely disuccinimidyl glutarate (DSG), disuccinimidyl suberate (DSS) and poly (ethylene glycol)-ylated bis (sulfosuccinimidyl)suberate (BS(PEG)₅), were evaluated, and DSS at a concentration of 500 μM was confirmed to be optimal. The E. coli-cell-based regenerable HRP immunoassay was evaluated employing three sequential HRP treatment and regeneration steps. Then, the Oms of E. coli cells were isolated and layered on a microplate and regenerable OM-based HRP immunoassaying was evaluated. Five HRP immunoassays with four regeneration steps were found to be feasible. This regenerable, covalently immobilized, orientation-controlled OM-based immunoaffinity layer was applied to an SPR biosensor, which was capable of quantifying C-reactive protein (CRP). Five regeneration cycles were repeated using the demonstrated immunoaffinity layer with a signal difference of <10%.     

交联剂对魔芋超强吸水剂凝胶强度和吸水倍率的影响

以魔芋葡甘聚糖为基体,丙烯酸为单体,过硫酸钾为引发剂,分别以N,N’-亚甲基双丙烯酰胺(MBA)、甘油、聚乙二醇600(PEG600)、Ca(NO3)2.4H2O为交联剂,制备魔芋超强吸水树脂(KSAP),测试其凝胶强度和吸水倍率,同时对其进行红外光谱结构表征。实验表明,以MBA为交联剂制得的KSAP的凝胶强度最大,可达到153.7g/cm2,以甘油为交联剂制得的KSAP的吸水倍率最高,可达1201g/g。