Preparation and characterization of supramolecular gel suitable for fractured formations

The excellent mechanical properties of supramolecular gel could adapt to the complex reservoir environment and had broad application prospects in the field of oil and gas drilling and production engineering.In this paper,a supramolecular gel based on hydrophobic association and hydrogen bonding was prepared by micellar copolymerization,which could be used to plug fractures and pores in formations.Supramolecular gel was a gel network system with high performance characteristics formed by self-assembly of non-covalent bond interaction.The rheological properties,mechanical mechanics,temperature resistance and swelling ability of supramolecular gel were studied.The results showed that the supramolecular gel had a dense three-dimensional network structure with open and interconnected pore structures,which could exhibit good rheological properties and strong viscoelastic recovery ability.The mechanical properties of the supramolecular gel were excellent,it had a tensile stress of 0.703 MPa and an elongation at break of 1803%.When the compressive strain was 96%,the compressive stress could reach 14.5 MPa.Supramolecular gel also showed good temperature resistance and swelling properties.At the aging temperature of 135℃,supramolecular gels still maintained good gel strength,and it only took 12 h to reach the equilibrium swelling ratio of 35.87 in 1%NaCl solution.It was also found that supramolecular gel in low concentration saline(1%NaCl solution)showed relatively faster swelling than high concentration saline(25%NaCl solution).The swelling process of the supramolecular gel was non-Fick diffusion(typeⅡ).This indicated that the organic/inorganic permeability network was well formed.Therefore,the diffusion rate of small molecules could be guaranteed to be equal to the relaxation rate of large molecules before and after the phase transition temperature.In addition to the diffusion of water molecules,the swelling process of the supramolecular gel was also affected by the relaxation of gel network and polymer chain segment,the interaction between water molecules and polymer network and the groups of polymer network and other factors.Supramolecular gel particles could be used as plugging materials for drilling fluids,which had excellent ability to plug formation fractures and pores.The plugging ability of the supramolecular gel was up to 6.7 MPa for 0.5 mm fracture width,and 9.6 MPa for porous media with 5 mD permeability.Compared with HT-PPG gel particles commonly used in oil fields,supramolecular gel particles had better plugging ability on fractures and porous media.The development and application of supramolecular gel had far-reaching significance for promoting the functional application of polymer materials in drilling and production engineering.

One-pot synthesis of network supported catalyst using supramolecular gel as template

A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as template.This procedure directly attaches ligand to support during fabricating the support.Using this strategy,supported CuBr/di-（2-picolyl） amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl methacrylate.XPS and SEM characterization of the catalyst revealed homogeneous distribution of ligand,sufficient reactive sites,adequate mechanical strength and macroporosity.The polymerization results demonstrated high activity and reusability of such catalyst.This strategy might be extended to other supported catalysts used in column reactors.

Regulation and application of supramolecular gel with circularly polarized luminescence

Supermolecular gel is a three-dimensional network structure assembled by small molecules or polymers in solvents through noncovalent interaction.The emergence of system complexity occurs spontaneously during the molecular self-assembly process.A multitude of chiral molecular self-assembly systems have been engineered,facilitating the achievement of circularly polarized luminescence(CPL)through the amalgamation of chiral entities with fluorophores.Hydrogen bonding,π-πstacking,and noncovalent forces,such as host-guest interactions and Van der Waals'forces,confer upon supramolecular gels the capacity to react to diverse stimuli.Due to the flexibility of supramolecular assembly,the CPL properties of supramolecular gels have rich controllability and can be used in various applications.In this review,we summarized the examples of CPL-active supramolecular gel assembly,and further summarized the assembly environment factors and external stimuli.Furthermore,the versatility of CPL applications in supramolecular gels is demonstrated,ranging from optical devices,information encryption,biosensing and chemical sensing,and other practical applications.In conclusion,the study provides insights into the multicultural factors influencing CPL in supramolecular gels,describes their applications in various domains,and presents future perspectives in the field.

Fabrication of palladium nanoparticles as effective catalysts by using supramolecular gels

Two-component supramolecular gels were made through self-assembly of tetrazolyl derivatives and Pd（OAc）_2. The robust gels indicated high storage modulus（〉10,000 Pa） and loss modulus, which were studied by rheological measurements. The formed Pd nanoparticles（~9 nm） obtained during the formation of the gel showed effective catalytic hydrogenation of nitrobenzene and could be recovered and reused without loss of activity.

Improved photostability of Vitamin A palmitate originating from self-assembled supramolecular gels

Retinyl palmitate(RP) is a derivative of Vitamin A and widely applied as the active component in the fields of cosmetic and pharmaceutics.RP can easily lose its physiological activity under UV irradiation due to its photosensitivity.In this work,it was found that the activity of RP remained 75% after 80 min of UVA irradiation when RP was entrapped in supramolecular gels formed by self-assembly of sorbitol-based gelators.By contrast,the activity of RP in conventional hydroxyethyl cellulose gels only remained 10% under the same conditions.These results showed that the supramolecular gels exhibited a significant protective effect on the photostability of RP.UV spectra of RP in supramolecular gels and corresponding solutions showed no distinct differences,indicating no change of the physicochemical properties of RP.The images of field-emission scanning electron microscopy and fluorescent optical microscopy suggested that the protection by supramolecular gels on the photostability of RP may be attributed to the three-dimensional network structure formed by the self-assembly of the gelators,which reduced the molecular collisions and the degradation process of the photoactivated RP.The present results showed that this protection can be influenced by the structures and the concentration of gelators as well as by the solvent composition.

A supramolecular gel based on an adenine symmetrically grafted Anderson-type polyoxometalate complex

An Anderson-type polyoxometalate was covalently decorated by using adenine on both sides.Through cation substitution,we obtained a new hybrid building block with long alkyl chains for supramolecular gels.According to the synergetic effect of hydrogen bonding of inter adenine units and van der Waals interaction of side alkyl chains,the DODA 3 [A-MnMo 6-A] gelator can stabilize solvent and self-assemble into fibrous structure,forming supramolecular gel.In addition,the reversible sol-gel transformation was achieved by controlling environmental temperature.Scanning electron microscopy,transmission electron microscopy and X-ray diffraction were used to characterize the gel morphology and structure.As a result,we proposed the possible mechanism of gel formation and sol-gel transformation.

Supramolecular gelator based on a [c2]daisy chain rotaxane:efficient gel-solution transition by ring-sliding motion

A supramolecular gelator based on the bistable [c2]daisy chain rotaxane is designed and synthesized. The reversible actuation of the [c2]daisy chain renders the formed supramolecular gel with acid/base-responsive switching between gel and monomer solution. The efficient switching process is attributed to the ring-sliding effect of the rotaxane in response to acid/base stimuli.The ring-inhibited hydrogen bonding stacking results in a nearly quantitatively disassembly of the gel network after addition of base which is hard to be realized by traditional heating strategy in hydrogen-bonding-supported gel.

Efficacy and Safety of 30% Supramolecular Salicylic Acid Peeling Combined with Isotretinoin Erythromycin Gel in the Treatment of Moderate-to-Severe Acne Vulgaris: A Comparative Study

Background: Both 30% supramolecular salicylic acid (SA) and isotretinoin erythromycin gel (IEG) have proven efficacy with good safety profiles in the treatment of acne vulgaris. Objectives: This study compared the clinical efficacy and safety of 30% SA peeling and IEG in the treatment of moderate-to-severe acne vulgaris. Methods: Patients with moderate-to-severe acne vulgaris were randomized into 3 groups of 30 persons each, and treated with SA peel, or IEG, or SA combine with IEG (SA + IEG group). Evaluation of acne was done by effective rate and individual lesion counts. And the adverse effects and recurrence were recorded. Results: The SA + IEG group was better in clinical efficacy and treating noninflammatory and inflammatory lesions than that of single treatment group (P 0.05). Conclusion: 30% SA combined with IEG had a significant effect in the treatment of moderate-to-severe acne lesions.

超分子凝胶药物递送系统研究进展

超分子凝胶是通过非共价相互作用以自组装方式形成的三维网络体系,由于具有良好的生物相容性、刺激响应性、凝-溶胶互变性及自愈合性,近年来在医药领域的药物递送及生物材料方面有大量研究报道。本文基于超分子凝胶形成原理归纳了超分子凝胶在药物递送领域中的研究现状,为以超分子凝胶为载体的新型给药系统相关研究提供参考。

弹流润滑状态下热可逆超分子凝胶润滑剂成膜机制的研究

轴承和齿轮等机械部件在平稳运转过程中处于弹流润滑状态,研究超分子凝胶润滑剂在弹流润滑状态下的润滑性能具有重要意义.主要研究了热可逆超分子凝胶润滑剂在弹流条件下的摩擦学性能,采用同步热分析仪和差示扫描量热仪分析了超分子凝胶润滑剂的相转变温度和热分解温度,证明该凝胶润滑剂具有良好的热学稳定性.采用流变仪分析了超分子凝胶润滑剂的流变学性能,证明该凝胶润滑剂具有良好的机械稳定性和触变性.通过光弹流润滑油测量仪研究了超分子凝胶润滑剂在弹流润滑条件下速度、载荷以及浓度对成膜机制的影响.结果表明:膜厚随着速度增大而增加,随着载荷增大而减小;乏油时间随着载荷和浓度增大而增加.通过微牵引力测定仪研究了载荷、滑滚比和温度对Stribeck曲线的影响,结果表明载荷越大摩擦系数越大,滑滚比越大摩擦系数越大,温度升高摩擦系数减小.试验证明超分子凝胶润滑剂具有比基础油和锂基脂更优异的摩擦学性能,是1种具有潜在应用价值的新型润滑剂.

基于紫甘蓝色素的智能凝胶材料及其甲醛变色研究

通过溶剂提取紫甘蓝中的花青苷色素(CabAn),在该色素化学结构的基础上,利用其质子化互变异构形成pH响应变色的特点,设计其与羟胺盐组合为超分子探针,通过甲醛与羟胺盐反应释放质子,而该质子则与花青苷的青绿色醌式体结合转化为紫红色吡喃鎓式,从而实现甲醛变色功能,并将超分子探针溶于琼脂制备成智能凝胶(CabAn_HA@Agar),按照国际照明委员会基于CIELab颜色空间定义色差的方法来测量计算甲醛浓度。

30%超分子水杨酸联合异维A酸红霉素凝胶治疗轻中度寻常痤疮的效果分析

目的:分析30%超分子水杨酸联合异维A酸红霉素凝胶治疗轻中度寻常痤疮的效果。方法:选取2022年1—12月临沂市河东区妇幼保健院及临沂市临沭县人民医院收治的60例轻中度寻常痤疮患者作为研究对象,按照随机数字表法分为对照组和观察组,各30例。对照组外用异维A酸红霉素凝胶治疗,观察组在对照组基础上联合30%超分子水杨酸换肤治疗。比较两组粉刺、丘疹、脓疱数量,治疗效果,不良反应发生情况。结果:治疗前,两组粉刺、丘疹、脓疱数量比较,差异无统计学意义(P>0.05);治疗后,两组粉刺、丘疹、脓疱数量少于治疗前,且观察组少于对照组,差异有统计学意义(P<0.05)。观察组治疗总有效率高于对照组,差异有统计学意义(P=0.011)。两组红斑发生率比较,差异无统计学意义(P>0.05);观察组烧灼感和干燥脱屑发生率高于对照组,差异有统计学意义(P<0.05)。结论:30%超分子水杨酸联合异维A酸红霉素凝胶治疗轻中度寻常痤疮的效果显著,可减少粉刺、丘疹、脓疱数量,但不良反应较多。

阿达帕林凝胶联合超分子水杨酸、医用冷敷贴治疗轻中度痤疮患者的效果

目的:探讨阿达帕林凝胶联合超分子水杨酸、医用冷敷贴治疗轻中度痤疮患者的效果。方法:选取2021年6月—2022年6月滨州医学院附属医院收治的150例轻中度痤疮患者为研究对象。根据简单随机化法将其分为对照A组(n=50)、对照B组(n=50)和观察组(n=50)。对照A组给予超分子水杨酸、医用冷敷贴治疗,对照B组给予阿达帕林凝胶治疗,观察组给予阿达帕林凝胶联合超分子水杨酸、医用冷敷贴治疗。比较两组临床疗效,症状改善时间,治疗前后的皮肤屏障功能。结果:治疗4周后,观察组总有效率(96.00%)高于对照A组(80.00%)和对照B组(72.00%),差异有统计学意义(P<0.05)。观察组红斑消失时间、疼痛消失时间、结痂时间、痂皮完全脱落时间均早于对照A、B组,对照A组红斑消失时间、疼痛消失时间、结痂时间、痂皮完全脱落时间均早于对照B组,差异有统计学意义(P<0.05)。治疗后,观察组经皮水分丢失(TEWL)低于对照A组和对照B组,对照A组TEWL低于对照B组,观察组角质层含水量高于对照A组和对照B组,对照A组角质层含水量高于对照B组,差异有统计学意义(P<0.05)。结论:阿达帕林凝胶联合超分子水杨酸、医用冷敷贴治疗轻中度痤疮患者能改善皮肤屏障功能,提高整体治疗效果。

主客体包合超分子凝胶颗粒调剖剂的制备及性能评价

预交联凝胶颗粒(PPG)被广泛用于治理油藏水流优势窜流通道,起到稳油控水的效果。为了解决常规共价结构的PPG强度不足、剪切恢复性能差以及不耐盐的问题,以烯丙基-β-环糊精(烯丙基-β-CD、主体功能单体)、十六烷基二甲基烯丙基氯化铵(C16DMAAC、客体功能单体)、N,N’-亚甲基双丙烯酰胺(MBA、交联剂)和丙烯酰胺(AM)为主要原料,研制了一种具有剪切恢复性能的共价-非共价协同交联结构的主客体包合超分子凝胶颗粒(S-PPG)调剖剂。采用流变仪、激光粒度分析仪、光学显微镜系统探究了S-PPG的流变性能、膨胀性能和耐盐性能。结果表明,主客体单体的最佳加量为总单体物质的量的2.5%与2.5%的S-PPG在地层水中膨胀24 h后,质量分数为0.6%时的弹性模量为73 Pa,是常规PPG的3.04倍;屈服应力为120 Pa,剪切黏度损失率为39%,剪切恢复性能和屈服应力均为常规PPG的4倍左右;地层水中的膨胀倍数达23。此外,随着盐含量的增加,S-PPG的膨胀性能逐渐增强,在Na Cl质量浓度为1×10^(5)mg/L下的膨胀倍数达27.9,表现出优异的耐盐性能。本文研究为油藏深部调剖提供一种具有潜力的抗剪切S-PPG材料。

璀璨星云——乙醇凝胶的焰色与变色

以超分子凝胶的制备为基础,结合焰色反应、酸碱指示剂变色和水解平衡移动等原理设计了一个综合性科普实验。实验采用乙酸钙水溶液和乙醇混合的方法制备凝胶,制备过程中加入金属盐(或硼酸)及酸碱指示剂,并调节酸碱性。制得的凝胶在燃烧时,金属盐(或硼酸)使火焰呈现出多彩的焰色,且受热导致凝胶中乙酸盐的水解平衡移动,使凝胶中的酸碱指示剂变色。整体实验效果绚丽多彩,如同璀璨的星云在宇宙中闪耀。本实验涉及知识点丰富,操作安全简便,现象明显,充分展现化学之美,满足不同人群的科普需求。

一种含芘葡萄糖衍生物的合成及其胶凝行为

合成并表征了一种荧光活性小分子胶凝剂--芘磺酰基-丙二胺-葡萄糖(PSDAPG),考察了其在36种常见溶剂中的胶凝行为.结果发现,PSDAPG可使其中16种溶剂胶凝.对癸醇,PSDAPG表现出罕见的超级胶凝能力,室温下最低胶凝浓度(MGC)达7.0×10-4g·mL-1.此外,PSDAPG还是一种既可胶凝水又可胶凝有机溶剂的双性胶凝剂.扫描电镜(SEM)、傅立叶变换红外光谱(FTIR)、核磁共振(1H NMR)和荧光光谱研究表明,在不同溶剂中,PSDAPG具有不同的聚集结构,除了芘基之间的疏水π-π堆积作用外,氢键作用是PSDAPG自发形成三维网络结构的重要驱动力.实验研究还表明,溶液态和凝胶态的PSDAPG荧光光谱均同时呈现芘的单体荧光和激基缔合物荧光光谱特征,但两者的光谱形貌差异显著.随凝胶的形成,体系单体荧光发射增强,激基缔合物荧光发射减弱,表明形成的三维网络结构阻碍了PSDAPG中芘单元的运动性,使得以Birks途径形成激基缔合物的效率降低.

超分子凝胶：结构多样性与超分子手性

超分子凝胶作为一种重要的软物质材料,在构建多重刺激响应性、光电功能,以及生物相容材料等功能软物质方面表现出了独特的优越性。超分子凝胶在形成过程中往往得到比较均一的纳米结构,且具有结构多样性;而另一方面,超分子凝胶的构筑单元大部分是手性分子,超分子凝胶也是实现手性在超分子层次/纳米层次表达的重要途径,尤其是手性传递、手性放大、不对称催化方面,同时超分子凝胶也是构筑手性纳米结构的重要手段。本文主要对超分子凝胶形成中的纳米结构以及形貌的多样性和超分子手性进行介绍,并展望该领域未来的发展方向。

自修复凝胶体系研究进展

自修复凝胶是目前自修复材料领域的研究热点之一,因其独特的性能在很多领域有潜在的应用。文中综述了近几年来国内外开发的最新自修复凝胶体系,重点介绍了几种超分子自修复凝胶体系,包括通过氢键作用自组装成三维网络结构的主-客体自修复凝胶、胆甾醇基自修复凝胶、甘露醇基自修复凝胶及通过金属配位作用形成的金属配体自修复凝胶。此外,还介绍了有机/无机粘土复合自修复凝胶体系、酰腙-双硫自修复凝胶、遥爪聚乙二醇-壳聚糖基自修复凝胶等其他新型自修复凝胶体系,同时对它们的自修复机理进行了简要的阐述,最后展望了其发展前景。

由凝胶因子形成的十四酸异丙酯超分子凝胶制备与表征

采用双十八烷基-L-苯丙氨酸(Bis18-L-Phe)为凝胶因子,制备了具有热可逆性的十四酸异丙酯(IPM)超分子凝胶。IPM凝胶相转变温度(Tgel)随Bis18-L-Phe浓度增大而增加。偏光显微镜(POM)显示在整个IPM凝胶中形成了相互缠绕的针状聚集体。FT-IR光谱分析表明Bis18-L-Phe分子间酰胺的氢键作用是IPM凝胶形成的一个重要驱动力。IPM凝胶动力学研究表明凝胶时间随Bis18-L-Phe浓度的增大而缩短,随着温度升高而延长,因此IPM凝胶时间可以通过温度和Bis18-L-Phe浓度调控。

基于ZnS纳米粒子的有机凝胶荧光薄膜的制备及其传感性能

本文首先采用油水界面法制备发光纳米ZnS粒子,再通过物理混合法,将其分散在溶有小分子胶凝剂的有机溶液中,流延于玻璃基质表面,得到ZnS荧光薄膜。实验结果表明,ZnS纳米粒子的平均粒径大小约为200 nm,具有立方晶型结构,并且在杂化薄膜中具有良好的分散性;胶凝剂形成的网络结构对ZnS纳米粒子具有良好的限域效应,表现为稳定的发光性能;气敏实验表明,该杂化膜对挥发性有机单胺和二胺具有灵敏的选择性传感作用;且其灵敏度随着杂化薄膜中ZnS担载量的增大逐渐提高;可逆性实验表明该薄膜对乙二胺蒸汽具有良好的可逆响应性。