Polyether Diamine Research Articles

Comparative study of styrenated-phenol and nonylphenol as accelerators in solvent-free epoxy primers

There have been significant and remarkable developments in the superior thermal and mechanical properties of polyether amine-based epoxy systems, which are frequently used polymers for a wide variety of industrial applications. Accordingly, this study focuses on styrenated phenol, which can be used as an accelerator or plasticizing agent in epoxy systems instead of nonylphenol. More particularly, it concerns the usage of styrenated phenol, which demonstrates excellent curing qualities for an epoxy system when combined with polyether diamine-based epoxy hardener and exhibits similar curing properties with nonylphenol. However, because polyether diamines cure slowly, they are combined with an accelerating agent, such as nonylphenol, which is harmful to the environment and human health. The goal of this research is to investigate the effect of polyether diamine curing chemistry on product performance changes in the epoxy primer at different stoichiometric ratios in the presence of styrenated phenol in the place of nonylphenol. These two raw materials can be used interchangeably, as demonstrated by test results comparing solvent-free epoxy primer to styrenated phenol and nonylphenol in terms of viscosity, compressive and flexural strength, gel time, and Shore D hardness. Consequently, it has been observed that styrenated phenol can be used instead of nonylphenol and that the same performance properties can be obtained. Test results have established that alterations occurred when the stoichiometric ratio of polyether diamine was reduced within limits and modified with a non-reactive diluent such as styrenated phenol in the epoxy-based primers.

Self-healing and reprocessable bismaleimide-diamine thermosets containing disulfide linkages

Mixtures of bis(2-maleimidoethyl) disulfide (BMIEDS), 4-aminophenyl disulfide (APDS), and Jeffamine® ED-600 (JA, an aliphatic polyether diamine) at a maleimide/NH2 ratio of 2/1 were prepolymerized at 170 °C and then compression-molded at 180 °C to obtain the cured products (BMIEDS-APDS-JAs). Similarly, BMIEDS/JA, bis(4-meleimidophenyl) disulfide (BMIPDS)/APDS/JA and BMIPDS/JA cured products (BMIEDS-JA, BMIPDS-APDS-JAs, and BMIPDS-JA) were prepared. The Fourier-transform infrared spectroscopy (FT-IR) of the cured products revealed that the maleimide/amine Michael addition reaction proceeded almost completely. The glass-transition temperature (Tg) and mechanical strength of the cured products decreased with the increase in JA weight fraction, and those of the BMIEDS-based cured products were lower than those of the BMIPDS-cured products. The highest JA fraction BMIEDS-APDS-JA and BMIESD-JA were healed three times at 100 °C, whereas none of the BMIPDS-based cured products exhibited self-healing properties. However, all the BMIPDS-based cured products were reprocessed by compression molding at 180 °C.

Pyrolysis and thermal degradation studies of non-isocyanate polyurethanes modified by polyhedral oligomeric silsesquioxanes

This work reports on the thermal properties of non-isocyanate polyurethanes (NIPUs) obtained via the polyaddition reaction of polyether diamine with five membered tri(cyclic carbonate) by using a prepolymerization method. The non-isocyanate polyurethanes were further chemically modified by trifunctional polyhedral oligomeric silsesquioxane (POSS) - triglycidylisobutyl POSS (3epPOSS), resulting in hybrid composite materials containing 5 to 15 wt% POSS. Thermal properties of the obtained materials were studied by various methods, such as Thermogravimetric analysis (TGA), Pyrolysis with gas chromatography and mass spectrometry (Py-GC/MS), and Microscale Combustion Calorimetry (MCC), and were later discussed in dependence of their composition and structure assessed by Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) techniques. FTIR spectra confirm the successful synthesis of NIPUs and their hybrids with POSS. The results of XRD and SEM revealed homogeneous distribution of silsesquioxane in the bulk of the NIPU matrix. Depending on the POSS concentration in the PU hybrids, various self-assembling structures were formed. TGA analysis indicated a two- and three-step degradation process of NIPU materials in inert and oxidative atmospheres, respectively. Significantly higher degradation temperatures and a remarkably reduced degradation rate for composite materials compared to unmodified NIPU matrix were observed during the second degradation step under an oxidative atmosphere. Based on the overall stabilization effect (OSE), hybrids containing 10 and 15 wt% of 3epPOSS were more thermally stable than the unmodified NIPU matrix. Py-GC/MS demonstrated that the products of NIPU thermal decomposition originate from hydroxyurethane moieties, main substrate core structures, and others, such as catalysts. Incorporation of 3epPOSS into the NIPU matrix decreases its flammability, as evidenced by the results of the MCC, with a nearly 20 % reduction effect noted for the composite with of 15 wt% of POSS, compared to the unmodified NIPU matrix. Importantly, chemical modification of NIPU by POSS caused a reduction of the heat of combustion in the final stage of degradation by ca. 30 %.

Programmable shape memory bismaleimide composite claw with two-way grabbing function

• A series of shape memory polymers (SMPs) based on bismaleimide (BMI) were synthesized. The BMI-based polymers are made of a 4,4'-bismaleimidodiphenylmethane (BDM) matrix and chain extender polyether diamine poly(propyleneglycol) bis(2-aminopropylether) (D400). Then crosslinking agent 2,4-tolylene diisocyanate (TDI) was added to form a crosslinking network. Last, it was toughened by adding liquid nitrile rubber (ETBN). • These BMI-based SMPs achieved wide T g ranges of 170-200 °C. This property allows these SMPs to remember two pre-deformed shapes. By designing the second pre-deformed shape similar to the original shape, the 2W-SME can be achieved. • Carbon fabric reinforced BMI-based shape memory composites (SMPCs) were prepared. By exploring the preparation process, the claw structure was formed with this BMI-based SMPC. The composite claw realizes the motion of reach out and grab 250g items. Functional polymer materials with a two-way shape memory effect (2W-SME) have attracted great interest recently. Herein, by introducing 2,4-tolylene diisocyanate (TDI) into the bismaleimide (BMI) network, the shape memory polymers we synthesized are a series thermosetting polymers with adjustable T g and triple-shape memory effect(triple-SME), and realized two-way behavior by programming. Those shape memory polymers (SMPs) were toughened by acrylonitrile-butadienerubber (ETBN) and reinforced with carbon fabric to make composites. The cured network with varying transition temperatures and flexibility was synthesized by varying the cyanate ester and rubber concentration in the system. Polymers with a broad glass transition temperature ( T g ) range can achieve triple-SME. Due to the complex cross-linked structure, the two-way behavior demonstrated above for BMI-based SMPs stem from its broad T g ranges. Select two temperatures higher and lower than T g as the switching temperature, and fix the pre-deformed shape in the opposite direction at these two temperatures to achieve the two-way behavior. These BMI-based SMPs could grab objects through the design of the structure. Results indicated that the above BMI-based SMPs with two-way function have excellent thermal stability and mechanical properties, which provides the basic attempts for the further development of thermosetting SMPs and their composite materials.

Plant oil-based non-isocyanate waterborne poly(hydroxyl urethane)s

With the increasingly depletion of the petroleum resources and awareness of the importance of environmental issues, a quest for a newer, safer and greener route for plant oil-based non-isocyanate waterborne polyurethanes is becoming one of the major challenges in the polyurethanes industry. In this study, the carbonated linseed oil (CLSO) was prepared from epoxy linseed oil, which was used to polymerize with different diamines and hydrophilic moiety to produce green and safety cationic, anionic and nonionic plant oil-based non-isocyanate waterborne poly(hydroxyl urethane)s (NIWPUs). Meanwhile, aromatic diamines, aliphatic diamines and polyether diamines were used as chain extenders to tailor the performance of the resulting plant oil-based NIWPUs, which also further evaluate the robustness of the proposed preparation route. The results showed that all the NIWPU dispersions exhibited excellent storage stability. The cationic NIWPU films showed good mechanical properties (the highest tensile property was more than 9 MPa and the highest elongation at break was more than 200 %) and antibacterial properties (antibacterial efficiency toward Staphylococcus aureus and Escherichia coli above 98 %), anionic NIWPU films exhibited good mechanical properties (the highest tensile property was more than 8 MPa and the highest elongation at break was more than 300 %) and coating performance (the highest pencil hardness was 7H and the highest crosshatch adhesion was 5B), and nonionic NIWPUs showed tailorable cloud points. The technique reported here offers a number of advantages, including low cost, easy performance, environmentally friendly and economical process, opening new platform for the production of NIWPUs prepared from plant oil.

Dynamic dielectric properties of isotactic polypropylene-g-maleic anhydride crosslinked by capped-end polyether diamine and filled with native or functionalized nano-graphite particles

Dynamic dielectric properties of an isotactic polypropylene matrix grafted with maleic anhydride (CA 100) and then crosslinked by polyether amine molecules and reinforced with different weight percentages of graphite nanoplatelets (GNPs), KNG180, were studied for the first time and compared to those obtained by DMA (Dynamic Mechanical Analysis). The main objective of this work was to investigate the reinforcement effect of GNPs focusing on the GNPs/matrix interfacial adhesion using dynamic dielectric relaxation spectroscopy in the frequency range from 0.1 Hz to 1 MHz and temperature range from 20 to 140 °C. The obtained interfacial polarization increments \({\Delta \varepsilon }_{\mathrm{MWS}}\) from MWS (Maxwell Wagners Sillars) relaxation showed a threshold value of 3% in weight of KNG180. This analysis suggests that interfacial compatibility between matrix and fillers in the case of nanocomposite KNG180 3 wt% is higher than those of other nanocomposites. A new plasma treatment was used to modify graphite nano-fillers to produce different types of nanocomposites. The 5 wt% plasma treated graphite nanocomposite shows a good dispersion of the nano-fillers but also a high value of \({\Delta \varepsilon }_{\mathrm{MWS}}\), which is an indication of high graphite/graphite interaction. This evolution could show that this material can be close to the formation of an electrical percolation network.

Determination of prohibition mechanism of cationic polymer / SiO2 composite as inhibitor in water using drilling fluid

Well drilling is complicated by wellbore inflation caused by saturation and swells in shale. Water-based drilling fluids (WDFs) were used to test the new NS-DD shale inhibitors, which is a nano-silicon dioxide/cationic polymer composite (NS-DD). Shale cuttings rolled restoration evaluations and bentonite inhibition evaluations were utilised to compare the inhibition performance of NS-DD to that of the classic inhibitory (Potassium Chloride) KCl and the widely used inhibitory polyether di-amine (PDA). Even at high temperatures, the inhibitory efficiency of nano silicon-dioxide was superior to that of KCl and PDA. However, when NS-DD was present, the restoration of shale was more than71.8% while hot rolling at 160 °C for 18 h in the occurrence of KCl as well as PDA. The third roll recovery of shale was 28.62 % and 42.15 % correspondingly. According to XRD obtained from WDFs filter cake and shale samples, the NS-DD adsorbs water into the reservoir and causes the shale to expand, therefore blocking water absorption into reservoir and producing shale swelling. This study showed that NS-DD might be used as a shale inhibitor in Water-based drilling fluids.

Investigation of the inhibition mechanism of polymer/nano-silica composite as shale inhibitor in water-based drilling fluids

Wellbore instability caused by shale hydration and swelling is the critical issue in the drilling process of oil and gas wells. In this study, the nano-silica/cationic polymer composite (NS-DD) was synthesized and evaluated as novel shale inhibitor in water-based drilling fluids (WDFs). The inhibition performance of NS-DD was carried out and compared with the conventional inhibitor potassium chloride (KCl) and the extensively utilized inhibitor polyether diamine (PDA), where the inhibition performance tests consisted of bentonite inhibition tests, linear swelling tests, and shale cuttings rolling recovery tests. The results revealed that NS-DD exhibited outstanding inhibition performance compared to KCl and PDA even in high temperature environment. Specifically, in the presence of KCl and PDA, the third roll recoveries of shale cuttings after hot rolling at 150 °C for 16 h were 28.62% and 42.15%, respectively, however, the recovery of shale cuttings was as high as 70.06% when NS-DD was attended. Additionally, we proposed that the excellent inhibition ability of NS-DD may be attributed to its strong adsorption with clay through hydrogen and ionic bonding and plugging of nano-pores in WDFs filter cake and shale, preventing water penetration into the reservoir causing shale hydration and swelling based on the results of scanning electron microscopy, zeta potential, thermogravimetric and X-ray diffraction analysis. This study revealed the potential application of NS-DD as the shale inhibitor in WDFs.

Synthesis of carboxymethyl chitosan as an eco-friendly amphoteric shale inhibitor in water-based drilling fluid and an assessment of its inhibition mechanism

To achieve potent inhibition, reduced environmental impacts and excellent compatibility between drilling fluid and shale inhibitors, an eco-friendly amphoteric inhibitor based on carboxymethyl chitosan (CMCS) was synthesized. The molecular structure of CMCS was characterized by potentiometric titration, Fourier transform infrared spectroscopy and nuclear magnetic resonance, and the carboxymethyl substitution degree was revealed to be approximately 0.94. The inhibition performance was evaluated through linear swelling and hot-rolling dispersion tests, and the results were compared with those obtained with low-molecular-weight cationic polyether diamine, high-molecular-weight non-ionic polysaccharide encapsulator, and potassium chloride. The interaction between clay particles and CMCS molecules was investigated by X-ray diffraction, scanning electron microscopy, surface wettability, particle size distribution, zeta potential and surface tension tests. The results showed that CMCS with a specific amphoteric molecular structure exhibited a different inhibition behaviour compared with conventional inhibitors, more effectively prevented clay hydration and swelling and inhibited shale disintegration at both 77 °C and 150 °C. CMCS could absorb onto the clay surface via electrostatic force and hydrogen bonding, and an encapsulation film was formed through intermolecular interactions to immobilize outer free water molecules and to provide hydrophobic characteristics. CMCS intercalates into clay lattice, expels inner water and reduces the interlayer space. Additionally, CMCS reduces the surface tension of the bulk solution and hinders fluid invasion. Furthermore, CMCS was compatible with bentonite dispersion and improved the rheological and filtration properties at a suitable concentration.

Study of Janus Amphiphilic Graphene Oxide as a High-Performance Shale Inhibitor and Its Inhibition Mechanism.

Janus amphiphilic graphene oxide (JAGO), modified by dodecylamine on one side of graphene oxide (GO), was investigated for its novel use as a shale inhibitor. JAGO was synthesized by the Pickering emulsion template technology and was characterized by the Fourier-transform infrared spectra, UV-vis spectra, and transmission electron microscopy. Compared to KCl (5%), polyether diamine (2%), and pristine GO (0.2%), JAGO's highest shale recovery rate (75.2% at 80°C) and lowest swelling height of Mt-pellets (2.55 mm, 0.2%) demonstrated its excellent inhibitive property. Furthermore, JAGO acted as a perfect plugging agent and greatly reduced filtration loss. Based on the results of X-ray diffraction, contact angle measurements, and pressure transmission tests, we proposed that the 2D nano-sheet amphiphilic structure of JAGO, which enabled it to be effective both in chemical inhibition and physical plugging, was responsible for its remarkable inhibition performances.

Lignin-Based Epoxy Resins: Unravelling the Relationship between Structure and Material Properties.

Here we investigate the relationship between thermomechanical properties and chemical structure of well-characterized lignin-based epoxy resins. For this purpose, technical lignins from eucalyptus and spruce, obtained from the Kraft process, were used. The choice of lignins was based on the expected differences in molecular structure. The lignins were then refined by solvent fractionation, and three fractions with comparable molecular weights were selected to reduce effects of molar mass on the properties of the final thermoset resins. Consequently, any differences in thermomechanical properties are expected to correlate with molecular structure differences between the lignins. Oxirane moieties were selectively introduced to the refined fractions, and the resulting lignin epoxides were subsequently cross-linked with two commercially available polyether diamines (Mn = 2000 and 400) to obtain lignin-based epoxy resins. Molecular-scale characterization of the refined lignins and their derivatives were performed by 31P NMR, 2D-NMR, and DSC methods to obtain the detailed chemical structure of original and derivatized lignins. The thermosets were studied by DSC, DMA, and tensile tests and demonstrated diverse thermomechanical properties attributed to structural components in lignin and selected amine cross-linker. An epoxy resin with a lignin content of 66% showed a Tg of 79 °C from DMA, Young’s modulus of 1.7 GPa, tensile strength of 66 MPa, and strain to failure of 8%. The effect of molecular lignin structure on thermomechanical properties was analyzed, finding significant differences between the rigid guaiacyl units in spruce lignin compared with sinapyl units in eucalyptus lignin. The methodology points toward rational design of molecularly tailored lignin-based thermosets.

Study of a gemini surface active ionic liquid 1,2-bis(3-hexylimidazolium-1-yl) ethane bromide as a high performance shale inhibitor and inhibition mechanism

It is an urgent subject to search high-performance shale inhibitors used in water-based drilling fluids for drilling safety. In the present work, two imidazolium-based ionic liquids (ILs), 1-hexyl −3-methylimidazolium bromide (BMH) and its corresponding gemini type, 1,2-bis(3-hexylimidazolium-1-yl) ethane bromide (HMH), were introduced as promising shale inhibitors. The inhibition performances were assessed and compared with the conventional inhibitors potassium chloride and polyether diamine (PDA) via the inhibition evaluation tests including sodium bentonite (Na-bent) pellets immersing tests, linear swelling tests and shale hot-rolling recovery tests. Both ILs inhibitors, especially HMH, shown terrific inhibition performance with lower dosages and maintained high-performance at temperature up to 160 °C. The inhibition mechanism was analyzed by FTIR, X-ray diffraction (XRD), Zeta potential tests, particle size distribution measurement, contact angle measurement and surface tension measurement. The results demonstrated both BMH and HMH effectively inhibit the shale hydration and swelling. HMH, with two positively charged headgroups and two hydrophobic tails, was better than BMH in entering the interlayer space of clay, reducing Zeta potential, forming hydrophobic shield and reducing the surface tension, which was responsible for its superior inhibition performance.

Reprocessable bismaleimide-diamine thermosets based on disulfide bonds

Mixtures of 4,4′-bismaleimidodiphenylmethane (BMI), 4-aminophenyl disulfide (APDS) and Jeffamine® ED-600 (JA, an aliphatic polyether diamine) at molar ratios of 2/1/0, 6/2/1, 4/1/1 and 6/1/2 were prepolymerized at 160 °C, and then hot-pressed at 190–210 °C to give cured products (BMI-APDS-21, BMI-APDS-JA-621, 411 and 612, respectively). Also, a cured product (BMI-APS-JA-621) of BMI, 4-aminophenyl sulfide (APS) and JA at a molar ratio of 6/2/1 was similarly prepared for comparison. The FT-IR analysis of the cured products revealed that the maleimide/amine Michael addition reaction almost completely proceeded. The glass transition temperature, thermal degradation temperature and rigidity for the cured products tended to decrease with increasing feed JA weight fraction. All the pulverized BMI-APDS-JAs were reprocessed by a hot press molding method at least three times, whereas BMI-APDS-21 was not reprocessed at all. BMI-APS-JA-621 was reprocessed only once, and its recovery rate for tensile strength was much lower than that of BMI-APDS-JA-621.

Investigation of inhibition mechanism of three deep eutectic solvents as potential shale inhibitors in water-based drilling fluids

Three different deep eutectic solvents CM-DES, CP-DES and CIM-DES were synthesized and investigated for their novel use as shale inhibitors. Their inhibitive properties were evaluated and compared with traditional inhibitor KCl and currently popular inhibitor polyether diamine (PDA) through the inhibition tests such as bentonite inhibition test, linear swelling test, shale cuttings hot-rolling dispersion test, etc. All three DESs presented remarkable inhibition performance with lower concentrations and performed quite well even at high temperature (160 °C). Based on the results of scanning electron microscopy, Zeta potential measurement, surface tension measurement, thermogravimetric analysis and X-ray diffraction analysis, we proposed that the great inhibitive properties of DESs were probably attributed to the electrostatic attraction and hydrogen bond between DESs and clay, and the different structures of DESs resulted in different inhibitive capacity. With the excellent inhibitive properties, the synthesized DESs demonstrated potential application as effective shale inhibitors in water-based drilling fluids.

Switching from brittle to ductile isotactic polypropylene-g-maleic anhydride by crosslinking with capped-end polyether diamine

Ductile functionalized polypropylene is of great interest in multi-layer composites development. A capped-end triblock polyether diamine (H2N-PO2-TMO9-PO3-NH2) was used as a linker of two different maleated isotactic polypropylenes (iPP-g-MAH, at 1 and 3 wt%) by twin-screw reactive extrusion. The molecular architecture, the semi-crystalline microstructure and the mechanical properties of the resulting polymers were analysed as a function of the molar ratio of NH2:MAH (0:1, 0.33:1, 0.5:1, 0.66:1, 1:1, 1.5:1, 2:1). At the molecular scale, the chemically modified polymers were characterized by FTIR and by the determination of gel content following the ASTM D2765-84 standard method. Differential Scanning Calorimetry, Wide Angle X-rays Scattering and Self Successive Auto-nucleation techniques showed the impact of the crosslinking: a decrease of the melting temperature as compared with the unmodified iPP-g-MAH polymer, as well as a decrease of the crystallinity ratio for the iPP-g-MAH at 3 wt% of MAH. Interestingly, Dynamic Mechanical Analysis and video-controlled uniaxial tensile tests showed that the polymers obtained in stoichiometric NH2:MAH molar ratio exhibit the best mechanical properties enlightened by a switch from brittle to ductile mechanical behaviour with few differences between the two iPP-g-MAH.

Design of Azomethine Diols for Efficient Self-Healing of Strong Polyurethane Elastomers.

Azomethine diols (AMDs) were synthesized by condensation between a terephthalic aldehyde, polyether diamine, and ethanol amine. The synthesized AMDs were employed to introduce azomethine groups into the backbones of polyurethane elastomers (PUEs). Different AMDs were designed to control the concentration and distribution of azomethine groups in PUEs. In this study, we explored the intrinsic self-healing of AMD-based PUEs by azomethine metathesis. Particularly, the effects of the concentration and distribution of the azomethine groups on the AMD-based PUEs were considered. Consequently, as the azomethine group concentration increased and the distribution became denser, the self-healing properties improved. With AMD3-40, the self-healing efficiency reached 86% at 130 °C after 30 min. This represents a 150% improvement over the control PUE. Additionally, as the AMD content increased, the mechanical properties improved. With AMD3-40, the tensile strength reached 50 MPa. Therefore, we concluded that the self-healing and mechanical properties of PUEs can potentially be tailored for applications by adjusting the concentration and design of AMD structure for PUEs.

Toughening of epoxy systems by brominated epoxy

Blends of brominated epoxy (BE) and conventional epoxy resins were studied following curing with aliphatic triethylenetetramine (TETA), etheric (polyether diamine‐ PEA4), and aromatic (3,3′‐diamino diphenyl sulfone [DDS]) hardeners. The addition of BE resulted in an increase in Tg in all tested blends. Blends with 50 wt% BE cured with TETA demonstrated an increase in flexural modulus and flexural strength, while preserving the elongation. Blends with 40 wt% BE cured with PEA4 and 50 wt% BE cured with DDS resulted in a significant enhanced tensile elongation. The shear strength of all cured systems decreased moderately with the addition of BE exhibiting a mixed mode failure. Analysis of the fracture morphology using electron microscopy supported the increase of toughness levels as a result of incorporating BE to conventional epoxy. A unique nodular and rough fracture morphology was obtained, which is related to a toughening mechanism caused by the addition of BE. It was concluded that blends of BE and conventional epoxy could be used as structural adhesives having high Tg, enhanced mechanical properties and increased toughness. POLYM. ENG. SCI., 59:206–215, 2019. © 2018 Society of Plastics Engineers

Tunable Thermosetting Epoxies Based on Fractionated and Well-Characterized Lignins.

Here we report the synthesis of thermosetting resins from low molar mass Kraft lignin fractions of high functionality, refined by solvent extraction. Such fractions were fully characterized by 31P NMR, 2D-HSQC NMR, SEC, and DSC in order to obtain a detailed description of the structures. Reactive oxirane moieties were introduced on the lignin backbone under mild reaction conditions and quantified by simple 1H NMR analysis. The modified fractions were chemically cross-linked with a flexible polyether diamine ( Mn ≈ 2000), in order to obtain epoxy thermosets. Epoxies from different lignin fractions, studied by DSC, DMA, tensile tests, and SEM, demonstrated substantial differences in terms of thermo-mechanical properties. For the first time, strong relationships between lignin structures and epoxy properties could be demonstrated. The suggested approach provides unprecedented possibilities to tune network structure and properties of thermosets based on real lignin fractions, rather than model compounds.

All-solid-state interpenetrating network polymer electrolytes for long cycle life of lithium metal batteries

All-solid-state interpenetrating network polymer electrolytes (INSPEs) were fabricated by a simultaneous reaction of 3-armed poly(ethylene glycol) methyl ether methacrylate-co-glycidyl methacrylate and bisphenol A diglycidyl ether (BPDE) with polyether diamine (ED2003) in the presence of LiTFSI, exhibiting high ionic conductivities at room temperature and remarkable stability towards lithium metal.

Experimental study on the application of an ionic liquid as a shale inhibitor and inhibitive mechanism

Wellbore instability is caused to a great degree by shale hydration, which results from the interaction between the exposed shale formation and water-based drilling fluids in the exploration of oil and natural gas reservoirs. In this paper, an ionic liquid (ILB) is utilized as an efficient shale inhibitor in water-based drilling fluids to minimize shale hydration. The inhibitive property of ILB is evaluated by hot-rolling dispersion, capillary suction time and bentonite swelling tests. The test results indicate that 0.05wt% ILB exhibits superior inhibition performance than 5wt% conventional inhibitor potassium chloride (KCl) and its inhibition effect is approximately equal to that of 2wt% polyether diamine (PA). But different from KCl and PA, the presence of low concentration of ILB can also improve the rheological properties of water-based drilling fluids at high temperature, and meanwhile has no adverse effect on their filtration property. The investigation of inhibition mechanism indicates that the thermal stability of Na-Mt is greatly improved due to the intercalation with cationic group of ILB, leading to excellent inhibition property of ILB at high temperature. Furthermore, the adsorption of ILB in the interlayer of Na-Mt weakens the hydrophilicity of Na-Mt, which further inhibits water ingress.