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This paper deals with the lessons learned during the completion design for a HPHT gas field (Field-X) offshore Sarawak, Malaysia. It is a carbonate reservoir with more than 500 meters of the gas column containing between 6-10 tcf of OGIP making it one of the major discoveries in recent years in this region. However, the combination of HPHT and the presence of about 18% CO2 and 2% H2S in the gas makes it a complex development, particularly for well and completion design.To address the challenges associated with the development of this field, a taskforce was formed with personnel from all relevant disciplines to come up with an appropriate design that can help produce from this reservoir safely. The project is now in the detailed design phase where the final aspects of the completion designs are being formulated. Considering that this will be one of the first development in this area with this combination of reservoir conditions, it is expected that the lessons learned from this project will support other future developments too.The paper discusses lessons learned during the design process specifically related to material selection for the highly sour environment, temperature modeling, identification of annulus pressure envelopes and their management, perforation philosophy, and surveillance methods for both reservoir management and well integrity.Another aspect which affects the overall well and completion philosophy for a complex development is the challenges associated with procurement and component qualification. At this stage, the key issues are being identified and will be briefly covered in this paper.

Ni3S2 nanowires were synthesized in situ using a one-pot hydrothermal reaction on Ni foam (NF) for use in supercapacitors as a positive electrode, and various contents (0.3−0.6 mmol) of Co(OH)2 shells were coated onto the surfaces of the Ni3S2 nanowire cores to improve the electrochemical properties. The Ni3S2 nanowires were uniformly formed on the smooth NF surface, and the Co(OH)2 shell was formed on the Ni3S2 nanowire surface. By direct NF participation as a reactant without adding any other Ni source, Ni3S2 was formed more closely to the NF surface, and the Co(OH)2 shell suppressed the loss of active material during charging–discharging, yielding excellent electrochemical properties. The Co(OH)2–Ni3S2/Ni electrode produced using 0.5 mmol Co(OH)2 (Co0.5–Ni3S2/Ni) exhibited a high specific capacitance of 1837 F g−1 (16.07 F cm−2) at a current density of 5 mA cm−2, and maintained a capacitance of 583 F g−1 (16.07 F cm−2) at a much higher current density of 50 mA cm−2. An asymmetric supercapacitor (ASC) with Co(OH)2–Ni3S2 and active carbon displayed a high-power density of 1036 kW kg−1 at an energy density of 43 W h kg−1 with good cycling stability, indicating its suitability for use in energy storage applications. Thus, the newly developed core–shell structure, Co(OH)2–Ni3S2, was shown to be efficient at improving the electrochemical performance.

The rational design and synthesis of multicomponent core@shell structures with fine morphology is a promising approach to develop electrode materials for advanced supercapacitors. In this study, Zn...

Mixed nanostructured transition metal-based complex materials with hierarchical and porous architectures, built from interconnected nano-building blocks, are considered as high-performance positive electrode materials in supercapacitors (SCs). Herein, zinc–nickel–iron phosphide (ZnNiFe–P) and Zn–Ni–Fe–hydroxide precursors (ZnNiFe–OH) were combined in a 3D hierarchical and porous structure (ZnNiFe–(P/OH)) to improve their durability and electrochemical activity by incorporating a dual-ligand synergistic modulation strategy. The 3D ZnNiFe–(P/OH) architectures, comprising perfectly aligned nanosheet arrays (NSA), were successfully grown on Ni foam using a facile hydrothermal process followed by partial phosphorization. The dual-ligand ZnNiFe–(P/OH) electrode exhibited excellent specific capacitance/areal capacitance (1708 F g−1/5.64 F cm−2 for 1 A g−1), high rate performance (62% upto 15 A g−1) and good cycle life. Moreover, the ZnNiFe–(P/OH) NSA positive electrode was coupled with an activated carbon negative electrode to design an asymmetric supercapacitor device. The device delivered an excellent capacitance of ∼187 F g−1 at 0.8 A g−1, a superior energy density of ∼58.4 W h kg−1 at 600 W kg−1, and an excellent power density of 11250 W kg−1 at 34.4 W h kg−1 while maintaining good cycling performance (88% after 5000 cycles).

Interest in CCS project development is accelerating in SE Asia, driven by the need to monetize emission-intensive assets in the region while complying with increasingly ambitious GHG emissions targets. Depleted hydrocarbon fields represent an attractive storage option for early CCS project due the enhanced understanding of the reservoir, its dynamic behavior, and proven storage capability. Re-use of existing infrastructure also presents the potential to reduce both project costs and time to first injection, however, these brownfield sites also carry significant risk to the long-term, safe containment of injected CO2 through risk of leakage via legacy wells. A methodology is presented in this paper to investigate the risk-reward balance of developing a depleted gas field as a storage site in the Gulf of Thailand. A screening process to assess all abandoned, suspended, and active wells is used to identify wells with re-use potential as CO2 injectors or CO2 plume monitoring wells, and those which represent a leakage risk to the project. A set of legacy well risk identifiers is generated for the field based on well construction records, descriptions of current well barriers, well utilization history, and current best practice guidelines. Southeast Asia has significant remaining reserves of oil and gas, and coal, and an active liquefied natural gas (LNG) export industry. The region's energy demand is increasing rapidly and is forecast to continue to grow over the next decades (World Economic Forum, 2019). To date, fossil fuels have supplied nearly 90% of this growth in the demand for energy in the region (IEA, 2021). To meet this growing energy demand, several new gas projects are under development across Southeast Asia, but many of these are associated with high CO2 gas fields where the produced gas contains significant (up to 70% by volume) CO2 (GCCSI, 2020). In Thailand, where nearly 94% of the primary energy is met by fossil fuels (BP Statistical Review, 2022), the energy sector represents the biggest contributor (74% in 2013) to the country's greenhouse gas emissions (GHG; UNFCCC, 2020). However, as per the nationally determined contribution to the United Nations Framework Convention on Climate Change (UNFCCC), Thailand intends to reduce its GHG emissions by at least 20% from projected business as usual levels by the year 2030 (UNFCCC, 2020). Carbon capture and storage (CCS) represents one option to help meet this increased demand in fossil energy while also reducing GHG emissions. An approach which is gaining traction across the region is to utilize the high concentrations of CO2 stripped out of the raw gas streams at gas processing plants and, instead of venting to atmosphere, the CO2 can be compressed, dehydrated, and transported to suitable long-term storage locations. Depleted oil and gas fields form an attractive opportunity for long-term storage of CO2 due to the wealth of both static and dynamic knowledge available from appraisal through production activities. Depleted fields also have the advantage that they have a working primary seal for hydrocarbons, which has been proven over geological time and so can be considered, in general, to carry low risk of leakage through geological means. Brownfield sites can, however, also represent a challenge to project success through an increased risk to the containment of the injected CO2 due to the presence of legacy wells. These existing wells represent a variable risk to containment depending on well age and type, well history, well design, and plug and abandonment methodology applied. This paper presents the outcomes of a CO2 storage feasibility study for a depleted gas-condensate field in the Gulf of Thailand. The main aims of the study were to:1) identify the project risk associated with the integrity of the field legacy wells, and 2) to evaluate the potential for well re-use for the CO2 injection project. Reusing an existing field offers new life to an otherwise end-of-life asset, inching towards decommissioning and site closure. As commercial scale CO2 storage in depleted hydrocarbon fields represents a ‘First of a Kind’ project, the feasibility study is designed to evaluate the current status of the field and surface facilities with respect to CO2 injection and long-term storage. As a feasibility study, the focus of the technical work was to identify any ‘showstoppers’ which might indicate that the selected site was not suitable for long-term CO2 storage and, if sufficient positive storage indicators were identified, to select the most appropriate options for progression into a Concept Selection study in which more detailed engineering studies will be completed.

Supercapacitors possess minimum energy density, lower rate capability, and inferior long-term cycling stability performance, and these issues have restricted their practical applications. In these ...

Well testing provides useful data for reservoir characterization during various stages of field life, from exploration, development to production. The key information that are typically can be obtained are, information on reservoir properties, deliverability, and pressure data. However, if the data acquisition during the well testing is compromised it can also lead to incorrect data and could lead to a wrong understanding of the reservoir and could results in sub-optimal field development. Therefore, it is important to emphasize on the quality of the data being acquired. This paper captures the experiences gained for a high-pressure-high-temperature (HPHT) exploration well DST where data acquisition was compromised in the 1st well drilled in the structure. A combination of temperature transient effect and tubing movement in the well during shut in resulted in data quality which can't be interpreted with confidence. The lessons learnt from the same was captured and addressed successfully in the subsequent well which enabled quality data acquisition. The objective of this paper is to share the challenges and mitigation strategies for a HPHT DST with the help of two DST operation where the challenges resulted in less-than-optimum data quality and the one where they were mitigated. The range of challenges came from planning, to gauge placement, to identify potential problems early, and even having proper contingency plans to cater for unplanned events. The paper also deals with some of the best practices which can help with any DST program. Key examples are pre-job modeling, accurate temperature measurement and modeling, real-time data acquisition, and a special focus on sampling as a part of a successful DST program. Disclaimer All parameters cited in this paper are purposely made in ambiguous manner to maintain confidentiality of the data.

Supercapacitors lack high energy density and long term stability, so a new class of hybrid material with hierarchical structure is desirable. Herein, for the first time we are reporting a rational design of hierarchical Cu-Ni(OH)2/Cu-MnxOy core/shell nanosheet arrays. The Cu-Ni(OH)2/Cu-MnxOy nanosheet arrays were synthesized by a two-step hydrothermal reaction. The as-synthesized Cu-Ni(OH)2/Cu-MnxOy hybrid structure exhibits ultrahigh areal and specific capacitances of 10.14 F cm−2 and 2535 F g−1, respectively at 3 mA cm−2. The electrode exhibits high rate-capability (59.37%) and excellent capacitance retention of 93.09% after 10 000 cycles. In Cu-Ni(OH)2/Cu-MnxOy core/shell hybrid structure, highly conductive and electroactive Cu-Ni(OH)2 core and Cu-MnxOy shell components played a vital role to develop a high-performance and stable electrode material. Furthermore, the unique porous structure of Cu-Ni(OH)2/Cu-MnxOy also provides enough space and short-diffusion lengths for Faradaic reaction. The asymmetric supercapacitors assembled of Cu-Ni(OH)2/Cu-MnxOy as positive electrode and GR/CNTs as negative electrode delivers a high specific capacitance of 267.15 F g−1 at a current density of 1 A g−1 with high-rate capability of 60.30%. Moreover, the as-assembled ASC device also shows an ultra-high energy density of 94.98 W h kg−1 at a power density of 759.89 W kg−1 and a maximum power density of 15 173.5 W kg−1 at an energy density of 57.28 W h kg−1 with capacitance retention of 89.79% after 10 000 cycles. These outstanding results suggest that Cu-Ni(OH)2/Cu-MnxOy hybrid structure can be considered as a cathode material for asymmetric supercapacitor in future.

A series of proton-functionalized graphitic carbon nitride (fgC3N4) modified reduced graphene oxide (rGO)/nickel-aluminium layered double hydroxide (LDH) composites (fgC3N4-rGO/LDH-1 and fgC3N4-rGO/LDH-2) were prepared by a novel scalable strategy using different amounts of fgC3N4-rGO as a conductive matrix. The morphological analyses reveal that the LDH sheets are gradually assembled on the fgC3N4-rGO matrix. The fgC3N4-rGO and LDH mutually minimize their self-aggregation in fgC3N4-rGO/LDH composite. The porous skeleton of fgC3N4-rGO/LDH-1 (highest loading of fgC3N4-rGO matrix) produces a high surface area (240 m2/g) and mesopores (diameter; 2.2 nm). The fgC3N4-rGO/LDH-1 electrode generates a specific capacitance value of 1190 F g−1 at 1 A g−1, excellent rate performance (71% at 10 A g−1), and good cycling stability (90% after 3000 cycles), in a three-electrode setup. Hierarchical fgC3N4 functionalized rGO composite (3D-fgC3N4@rGO) was used as a negative material. The 3D-fgC3N4@rGO produces an excellent capacitance of 345 F g−1 at 1 A g−1, high rate capability (74% at 10 A g−1) and good cyclic stability (90% after 3000 cycles). The fgC3N4-rGO/LDH-1 and 3D-fgC3N4@rGO were assembled to fabricate a solid-state asymmetric supercapacitor device using KOH/PVA gel electrolyte. The device operates within the potential window of 1.6 V and produces the highest energy density and power density of 54.76 W h kg−1 and 12031.92 W kg−1, respectively. The solid-state device shows an excellent cycle life of 91% after 7000 cycles, and it can power a red LED, suggesting very efficient for practical application.

Herein, we synthesized few-layered water dispersible two dimensional (2D) MoS2 nanosheets using thiourea by a facile hydrothermal method. The MoS2 nanosheets consisted of graphene-like structures that are 4 nm in thickness and ∼2 μM in size as observed from AFM analysis. The incorporation of MoS2 nanosheets into the poly(vinyl alcohol) (PVA) matrix significantly improved the thermal and dielectric properties of the fabricated nanocomposites (PVA-MoS2). The nanocomposite films demonstrated tremendous enhancements of the tensile strength (56%), modulus (42%), and toughness (more than 300%) after incorporation of 2 wt% of MoS2 nanosheets. The nanocomposite films also exhibited outstanding barrier towards hydrogen; specifically, the nanocomposite with 2 wt% of MoS2 nanosheets exhibited a decrease of almost 94% in its permeability than the PVA film for hydrogen gas. Different theoretical models have been applied to investigate the nature of dispersion of MoS2 inside the PVA matrix based on tensile modulus and permeability.

A new series of boric acid (BA) induced cross-linked poly(vinyl alcohol-co-ethylene) (EVOH)/graphene oxide (GO) nanocomposite (EVOH/BA/GO) films are prepared using different amount of GO and BA with respect to EVOH. The EVOH/BA/GO nanocomposites are respectively coated on nylon films and stainless steel substrates by a typical spray coating method, followed by thermal and hydrazine vapor treatment for gas barrier and corrosion studies. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses confirm the formation of cross-linked nanocomposite through the formation of B–O–C bond. The field emission scanning electron microscopy analysis indicates the formation of homogeneous structure for these nanocomposites. The storage modulus (at 25 °C) and elastic modulus of EVOH/15BA/5GO-coated film with 15% BA and 5% GO are enhanced by 280 and 60%, respectively, in comparison to nylon film. EVOH/15BA/5GO-coated nylon film exhibits dramatic reduction of hydrogen (6.9) and oxygen gas (1.5) transmission rates (cc/m2∙d∙atm) than pure nylon film. In addition, EVOH/15BA/5GO-coated stainless steel shows an ultralow corrosion current (0.294 μA/cm2) and corrosion rate (3.43 × 10−3 mm/year) than steel. A comparative study between EVOH/BA/GO and EVOH/GO is performed to examine the effect of the cross-linker on the different physical properties.

The octadecylamine (ODA) modified graphene oxide (mGO-ODA)/maleic anhydride grafted polypropylene (MAPP) composites (mGO-ODA/MAPP) were prepared and applied successfully as gas barrier and corrosion protection coating materials for the first time. The hydrophobic mGO-ODA sheets showed improved solubility in non-polar solvents with molar absorptivity was found to be 36 mL mg−1 cm−1 in ethylcyclohexane. FTIR analysis confirmed that mGO-ODA chemically interacts with MAPP. The mGO-ODA nanosheets were well exfoliated and dispersed in the MAPP matrix as confirmed by XRD analysis. The mGO-ODA/MAPP composites were coated on modified nylon sheets by a spray coating method, and the gas transmission rates (GTRs) of H2 and O2 were tested for these coated films. Cross-sectional FESEM showed the excellent attachment of these composite with the nylon film. The 60% mGO-ODA/MAPP-coated nylon film exhibited 93% and 112% improvement in elastic modulus values than the MAPP-coated and pure nylon films, respectively. Besides, 60% mGO-ODA/MAPP exhibited 94.1% and 95.0% reduction for H2GTR and O2GTR, respectively, compared to the pure nylon film. In addition, mGO-ODA/MAPP coated steel substrate exhibited excellent anticorrosion performance. The corrosion inhibition efficiency and corrosion rate were calculated to be 99.15% and 2.26 × 10−3 mm/year, respectively, for 60% mGO-ODA/MAPP.

In this study, a novel 4,4′-diaminostilbene-2,2′-disulfonic acid (DASDSA)-functionalized reduced graphene oxide (DASDSA-rGO) was prepared via simple refluxing method involving GO and DASDSA in the presence of ammonia solution followed by reduction with hydrazine hydrate. FTIR spectroscopy, Raman scattering, X-ray photoelectron spectroscopy (XPS), and XRD analyses confirmed the successful functionalization and reduction of GO in DASDSA-rGO. The FTIR and XPS analyses also confirmed covalent bond formation between DASDSA and graphene. The DASDSA spacer successfully minimized the restacking of rGO sheets as observed from FESEM analysis. Several redox transition states and SO 3 H groups of grafted DASDSA moieties provided excellent pseudocapacitance performance of the DASDSA-rGO electrode. The DASDSA-rGO electrode showed high specific capacitance ( C ) value of 1042 F g −1 at a current density of 1 A g −1 , good cycling stability (95% capacitance retention after 3000 cycles), and excellent rate capability in a three-electrode setup. The DASDSA-rGO (positive electrode) and rGO (negative electrode) were assembled to prepare an asymmetric supercapacitor (ASC) device. The power density values of the ASC device were calculated to be 650 and 7800 W kg −1 at energy density values of 37.37 and 23.78 W h kg −1 , respectively. The ASC device exhibited C value of 159 F g −1 at 1 A g −1 and displayed 86% retention in C after 8500 cycles. The EIS data of the three-electrode system and ASC device were fitted with Z-views to determine the different resistance components after a different number of charge–discharge cycles in a cycling stability test.

A hydroxylated boron nitride (BN(OH)x) functionalized p-phenylenediamine modified reduced graphene oxide (rGO) filler (BN(OH)x–PrGO) is synthesized for the first time using a facile and novel strategy. BN(OH)x–PrGO/polyurethane (PU) composite films are prepared using different filler loadings via a solution casting technique. BN(OH)x–rGO/PU and BN(OH)x/PU composite films are also prepared in order to compare the reinforcing effects of different fillers. FESEM and TEM analyses show the excellent dispersion and compatibility of BN(OH)x–PrGO sheets in the PU matrix. The tensile strength and modulus of the composite film show 62% and 95% enhancement, respectively, following the inclusion of 3 wt% BN(OH)x–PrGO compared to those of the pure PU film. The BN(OH)x–PrGO/PU composite films exhibit outstanding oxygen gas barrier properties, ideal dielectric properties, and excellent anti-corrosion performances. In particular, the 3BN(OH)x–PrGO/PU film shows nearly 91% reduction in the O2 transmission rate compared to the PU film. The permeability of O2 through the composite film is correlated with the diffusivity, solubility and Bharadwaj model. The dielectric constant (at 103 Hz) increases from 6.8 for the pure PU film to 13.1 for the 3BN(OH)x–PrGO/PU composite, and the dielectric loss also remains low for the composite. The potentiodynamic polarization curve shows a substantial shift of the corrosion potential of 3BN(OH)x–PrGO/PU-coated steel towards the anodic direction compared to the PU film, and it exhibits an ultralow corrosion rate (6.14 × 10−5 mm per year) and excellent corrosion inhibition efficiency (99.96%) in saline solution.

In this study, the self-assembled Ni(OH)2-nanosheet-adorned hierarchical MCo2O4@Ni(OH)2 (M = Zn or Mn) core@shell heterostructures are prepared by a three-step process, via tuning the core-compositions, as advanced electrodes for supercapacitors (SCs). The tuning of the core composition makes a significant impact on the physicochemical properties, morphology, and electrochemical performance. Among the MCo2O4@Ni(OH)2 materials, the nanopine forest-like ZnCo2O4@Ni(OH)2 optimal architecture exhibits superior supercapacitive performance (areal/specific capacity, 1.34 mA h cm−2/432.6 mA h g−1 at 3 mA cm−2 current density and a ∼90% cycling stability upto 5000 cycles). Meanwhile, 3D porous nitrogen-doped carbon (PNC) with perfect rhombic dodecahedral morphology is used as negative electrode material with high surface area (1600 m2 g−1), excellent capacity (49.2 mA h g−1 at 2 mA cm−2) and rate performance (∼55% at 50 mA cm−2). The solid-state asymmetric device comprising ZnCo2O4@Ni(OH)2 (positive electrode) and hierarchical PNC (negative electrode) affords a high cell capacity of 97.8 mA hg−1 at 4 mA cm−2, with 86% cycle stability after 10,000 cycles. Moreover, the device exhibits 78.2 W h kg–1 of energy density at a power density of 451 W kg−1 and 40.4 W h kg−1 of energy density at 4691.0 W kg−1 of power density. This study provides insight into electro-active material design and construction of heteronanostructures for high-performance SCs.

In this study, the organo-soluble dodecylamine amine (DDA)-modified reduced graphene oxide (DDA-rGO) was synthesized using two different grafting methods. DDA was covalently bonded with GO sheets by direct amidation processes in the presence of N,N′-Dicyclohexylcarbodiimide (DCC), followed by reduction with hydrazine hydrate to prepare the DDA-modified reduced GO (DDA-rGO1). Analogous DDA-modified rGO (DDA-rGO2) was prepared by modifying GO with DDA in the absence of DCC. The ultraviolet−visible spectra showed that the DMF dispersion of DDA-rGO1 and DDA-rGO2 followed Beer's law and their molar extinction coefficient values were calculated to be 64 and 44 mL mg −1 cm −1 , respectively. The AFM, TEM, and TGA confirm the higher amount of DDA attached in DDA-rGO1. These fillers with various loading amounts were successfully used to synthesize several composite films using polyurethane (PU) as matrix. All nanocomposites showed excellent improvement in mechanical and gas barrier properties than PU. DDA-rGO1-4/PU with 4 wt% DDA-rGO1 improved the tensile modulus ( E ) by 204% and reduced O 2 permeability ( P ) to 84% compared to PU. On other hand, DDA-rGO2-4/PU enhanced the E by 122% and declined P to 80% compared to PU. The DDA-rGO1 demonstrated a better reinforcing efficiency to improve the mechanical and gas barrier properties.

We report the simultaneous reduction, surface modification, and stitching of graphene oxide (GO) by ethylenediamine (EDA) and triethylenetetramine (TET) to boost the hydrogen gas barrier performance of polyurethane (PU) composite-coated nylon films. TEM and XRD analyses confirmed the formation of stitched EDA-modified GO (EDA-mGO) and TET-modified GO (TET-mGO) while FT-IR spectroscopy, Raman spectroscopy, and thermogravimetric analyses revealed the functionalization and reduction of GO by EDA and TET. EDA-mGO/PU and TET-mGO/PU composites were synthesized using different amounts of EDA-mGO and TET-mGO, respectively, and composites were deposited onto surface modified nylon films by spray coating to prepare hydrogen barrier films. FTIR, XRD, and FESEM analyses showed that both EDA-mGO and TET-mGO were uniformly dispersed into PU matrix. Cross-sectional FESEM showed strong adhesion between the nylon and composites. Coated films exhibited dramatic reduction in hydrogen gas transmission rate (H2GTR) and TET-mGO/PU with 22 wt% TET-mGO exhibited 93% decrease in H2GTR than bare nylon film.

A facile approach for the fabrication of chemically-modified reduced graphene oxide (RGO) based multilayer films was developed for gas barrier applications. Polyethyleneimine (PEI) and poly(sodium 4-styrenesulfonate) (PSS) were utilized as surface modifiers to yield water-dispersible RGO with opposite charges. Altering the deposition pH of PEI-RGO layer resulted in different phase morphology and bonding of the multilayer films. PEI-RGO and PSS-RGO were assembled into multilayer films via a layer-by-layer (LbL) assembly method through electrostatic and hydrogen bonding interactions, respectively. The LBL assembly of polymer-decorated RGO based multilayer films were characterized by various characterization techniques. Hydrogen gas transmission rate (H2GTR) of the hydrogen bonding interaction based LbL film with 24 bilayers was 5.8 cc/m2·d·atm; and H2GTR value was 46.2 cc/m2·d·atm for the corresponding LbL film based on electrostatic interactions. Hydrogen bonding interaction based multilayer films exhibited very low H2GTR values compared to electrostatic interaction based multilayer and bare polyethylene terephthalate films.

Seismic well tie is a critical process to verify the time-depth relationship of a well. This process requires density and sonic transit time data. However, sonic logs are usually not acquired due to cost saving, unfavorable well path, or other operational issues. Attempts to generate synthetic logs by Gardner equation, porosity correlation, or depth correlation did not provide the required accuracy. Therefore, the goal of our project was to generate synthetic sonic logs using machine learning technique for seismic well ties. This paper will compare the different methods tested, compare the results and lists the advantages of using Machine Learning. This approach uses machine learning technique to create synthetic sonic logs. The machine learning model is trained to predict sonic log from other relevant logs. The model representativeness is confirmed by blind tests, which consists of two steps. The first step compares the synthetic sonic logs to the actual sonic logs. In the second step, four synthetic seismograms are generated from actual sonic, machine learning synthetic sonic, Gardner predicted sonic, and averaged constant sonic. The seismic well ties are compared between those four synthetic seismograms. Once the machine learning synthetic and actual logs show similar results, the model is deemed good and can be applied on wells that do not have sonic logs. The synthetic seismograms are then generated using synthetic sonic logs for all the wells that do not have actual sonic logs. The use of synthetic sonic logs gives us the ability to Generate synthetic seismogram to tie wells that do not have sonic dataReduce the number sonic data acquisition, saving time and moneyReduce the risk of long logging string getting stuck in the hole that would requires fishing operations and its associated cost.

Greater Bongkot North is a gas field located in Gulf of Thailand and on production since 1993. Most of the old wellhead platforms (30%) lack remote well test facilities which requires personnel visits for any well test measurement. Often, well testing in these platforms get lower priority compared to other operations in a matured field. This project implemented artificial intelligent (AI) technique to estimate gas rate from other available engineering and geological parameters. A new approach using machine learning was applied to estimate gas production rate where actual measurements are not available. Actual production well test data was used to train the model. Input parameters used were: Surface facility information Fluid properties Production condition Geological setup A blind test on the subset of historical data showed a level of confidence (R2) value of 0.93. This provided confidence to proceed with a full field pilot. A pilot was conducted during January to May 2018. The area of pilot was spread across various geological, operating and surface condition setups to reduce sampling bias. The pilot demonstrated the following use cases: Improved prediction accuracy in wells with no recent test, achieving primary object of model. Detection of well behavior changes: The model could detect changes in well behavior without human intervention much before the trends become obvious for engineers to detect. Improved potential estimation in wells with leaks in wellhead chokes where conventional analysis followed in Bongkot is not possible due to improper wellhead shut-in pressure measurement. Improved efficiency with production allocation: The conventional method requires significant time (40-80 person hours per month) to make the data available for production allocation. This can be shortened significantly by use of this method In essence, this project demonstrated the potential use of artificial intelligent to improve efficiency in a matured gas field operating under marginal conditions.

Sulfonated polyaniline (SPANI) functionalized reduced graphene oxide (SPANI/G-1) was prepared by aniline initiated polymerization of m -aminobenzene sulfonic acid in presence of graphene oxide (GO), followed by reduction with hydrazine hydrate. Fourier transform infrared, Raman, and X-ray photoelectron spectroscopy analyses confirmed successful surface modification of graphene using SPANI. The presence of sulfonic acid groups in SPANI accelerated the redox reaction and provided pseudocapacitance. SPANI/G-1 based electrode showed high specific capacitance of 1107 F g −1 at a current density of 1 A g −1 in a three electrode set up. An asymmetric supercapacitor (ASC) device was fabricated using SPANI/G-1 as positive electrode and chemically reduced GO (RGO) as a negative electrode. ASC showed specific capacitance of 157 F g −1 at a current density of 1.5 A g −1 and 94% retention in specific capacitance after 5000 charge-discharge cycles at a current density of 3.8 A g −1 . The ASC exhibited maximum energy density of 31.4 W h kg −1 and a large power density of 14,764 W kg −1 . Nyquist data of the device was fitted with Z-view and different components (solution resistance, charge-transfer resistance and Warburg elements) were calculated from the fitted curve.

Fabrication of high-performance graphene-based polymeric composites is challenging due to poor dispersion of graphene caused by restacking, weak interfacial bonding, and incompatibility of graphene with polymers. Herein, reduced graphene oxide (rGO)-based polyethyleneimine (PEI) composite (rGO/PEI) was synthesized by utilizing the unique roles of PEI as reducing agent and surface modifier to overcome the above-mentioned drawbacks of graphene. Composites with different graphene oxide (GO):HPEI ratios were used to prepare rGO-high molecular weight PEI (rGO/HPEI). For potential application as hydrogen gas barrier material, rGO/HPEI composites were coated onto the polyethylene terephthalate (PET) substrates through spray coating technique to prepare gas barrier films. Analogous rGO/LPEI (low molecular weight PEI) coated PET film was also prepared. The rGO/HPEI composite-coated films showed dramatic enhancement in hydrogen gas barrier properties and excellent tensile strength with high elongation at break as compared to PET and rGO/LPEI coated PET films.

A series of novel polyethyleneimine (PEI) modified graphene oxide (PEI-mGO) filled poly(vinyl alcohol) (PVA) nanocomposite (PEI-mGO/PVA) films were prepared by solution-casing for hydrogen gas barrier applications. Hydrophilic PEI was used to simultaneously reduce and modify graphene oxide sheets, thereby facilitating a homogeneous dispersion of PEI-mGO in the PVA matrix. The effects of PEI-mGO on the morphology and properties of the nanocomposite films were examined by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis and field emission scanning electron microscopy. Analogous GO/PVA composites were also prepared and characterized for comparative purposes. The PEI-mGO/PVA nanocomposites showed higher thermal and mechanical stability as well as remarkable improvement in hydrogen gas barrier properties compared to the PVA film; specifically, the PEI-mGO/PVA film having 3.0 wt% of PEI-mGO content exhibited almost 95% decrease in GTR and permeability values compared to PVA film.

Transition-metal-based nanomaterials are preferred for electrochemcial supercapacitor applications owing to their low purchasing cost, facile synthesis process and high theoretical electrochemcial performance. However, these materials can not translate their excellent theoretical performance into commendable experimental values. In these circumstances, supercapacitors based on new class of highly conductive and electroactive hybrid nanomaterial are recommended. Herein, for the first time, 2D CuMnO2-MnxOy@graphene foam (GF) hybrid nanomaterial is constructed as a novel electrode material for asymmetric supercapacitor application. The CuMnO2-MnxOy@GF hybrid nanomaterial displays an excellent areal capacitance of 7.82 F cm−2 at a current density value of 3 mA cm−2, while it also maintains maximum areal capacitance of 67.51% at 60 mA cm−2. The CuMnO2-MnxOy@GF hybrid nanomaterial retains a high capacitance of 92.15% after maximum 10,000 cycles. A high-performance asymmetric supercapacitor device is assembled based on CuMnO2-MnxOy @GF and sulfur-nitrogen-codoped graphene nanosheets (SN-GNs) as positive and negative electrode materials, respectively. The CuMnO2-MnxOy @GF//SN-GNs ASC device shows an ultra-high energy density value of 81.4 W h kg−1 at a minimum power density of 809.5 W kg−1. The CuMnO2-MnxOy @GF//SN-GNs ASC device retains a specific capacitance of 88.88% after 10,000 cycles. The CuMnO2-MnxOy@GF hybrid nanomaterial is beneficial to promote asymmetric supercapacitor device with an excellent electrochemcial performance.

The rational design and subsequent growth of apposite nanostructured transition metal sulfide on conductive scaffold with auspicious morphology to produce an advanced electrode material for supercapacitors is highly desirable to boost the electrochemical performance. Herein, a simplistic two-step strategy is designed to grow 3D-networked and mesoporous Zn–Ni–Co–S nanowire-like arrays (NWAs) on a Ni-foam scaffold, which includes the hydrothermal growth of Zn–Ni–Co-based hydroxyl precursor, followed by an effective sulfidation process. When employed as a free-standing electrode for supercapacitors, Zn–Ni–Co–S NWAs electrode delivers a superb capacity of 418.2 mA h g−1 at 4.6 mA cm−2, good rate capability (233.3 mA h g−1 at 50 mA cm−2), and long cycle life (~89% of capacity retained after 10,000 cycles). Furthermore, a solid-state asymmetric supercapacitor device was constructed based on Zn–Ni–Co-S NWAs as cathode and graphitic carbon nitride/graphene as anode materials, achieves a cell capacity of 110.7 mA h g−1 at 5 mA cm−2, superior capacity retention (54% at 75 mA cm−2) and superb cyclic performance (93% after 10,000 cycles). The device delivers a superb energy density of 88.6 W h kg−1 at a power density of 419.4 W kg−1, and upholds an energy density of 47.6 W h kg−1 at a high power density of 7048.4 W kg−1.

A series of modified 2D nanosheets (graphene oxide-layered double hydroxide, GO-LDH; boron nitride-LDH, BN-LDH; and molybdenum disulfide-LDH, MoS2-LDH) are prepared via a cost-effective, environmentally-friendly, and effortless method based on the concept of electrostatic interaction. The modified 2D nanosheet/Poly(vinyl alcohol) (PVA) nanocomposite films show a comprehensive improvement of physicochemical properties. Among the synthesized films, the O2 barrier performance of the 1% GO-LDH/PVA nanocomposite film (1.44 × 10−13 cm3 cm/cm2·s·cmHg) is 25-fold higher than that of the pure PVA film (3.68 × 10−12 cm3 cm/cm2·s·cmHg). The 1% GO-LDH/PVA shows tremendous improvement in tensile strength (84.7 MPa) and modulus (3032 MPa) values than the PVA film (46.7 and 371 MPa). Furthermore, the 2% BN-LDH/PVA nanocomposite shows the H2/CO2 permselectivity value of 102.5, which is superior to the Robeson upper bound and most reported separation films. In addition to the improved gas barrier and permselectivity performances, an exceptional combination of the thermal stability, tensile strength/modulus, flexibility, and transparency of the nanocomposite film could lead to applications in food packaging, H2 purification, and CO2 capture.

Hexylamine (HA) functionalized reduced graphene oxide (RGO-HA) was prepared via the modification of graphene oxide (GO) with HA, followed by reduction with hydrazine hydrate. The structure of RGO-HA was confirmed using various characterization techniques. RGO-HA was easily dispersed in several organic solvents due to its hydrophobic nature. Accordingly, RGO-HA/polyurethane (PU) composites were synthesized using different amounts of RGO-HA for their potential application in the field of barrier materials. Fourier-transform infrared spectroscopy (FTIR), wide angle X-ray diffraction (WAXS) analysis, and field emission scanning electron microscopy (FESEM) showed that RGO-HA in PU was fully exfoliated and uniformly dispersed. The hydrogen gas barrier films were prepared by spray coating of RGO-HA/PU nanocomposite solutions on nylon films. Good attachment between the nylon surface and nanocomposite was confirmed by cross sectional field emission scanning electron microscopy. The nanocomposite coated nylon film having 43.3 wt% RGO-HA exhibited an 82% decrease in the hydrogen gas transmission rate (GTR) compared to a pure nylon film. The high reduction in GTR values of the coated films may motivate to use alkyl amine-modified reduced graphene oxide and PU nanocomposite for the future development of effective barrier materials.

A new diamine monomer, 2′,7′-bis-[2″-trifluoromethyl 4″-( 4 ‴ -aminophenyl)phenoxy]-spiro[fluorene-9,9′-xanthene] was successfully used to synthesize several polyamides (PAs) for membrane-based gas separation applications. All synthesized polymers were soluble in organic solvents, exhibited high molecular weight, high thermal stability (up to 483 °C and 519 °C in air and nitrogen respectively, for 10% weight loss) and high glass transition temperature (273–289 °C). The optically transparent membranes (λcut-off ⩾ 364 nm) from these PAs showed tensile strength up to 88 MPa with elongation at break up to 12%. In general, the membranes prepared from these polymers showed very good combination of permeability and permselectivity for a pair of gases. It has been attempted to draw a structure–property correlationship between the chemical structures of the polymers and their gas transport properties on the basis of their FFV, glass transition temperatures, intersegmental distance and dielectric constant values.

A series of processable new aromatic polyamides (PAs) were prepared by the reaction of a new diacid monomer namely, 2,6-bis[3′-trifluoromethyl-4′(4″-carboxyphenoxy)benzyl]pyridine and previously reported four diamines monomers. The synthesized PAs showed high thermal stability (up to 468 °C in air, for 10% weight loss), high glass transition temperature (243–254 °C) and tensile strength up to 95 MPa. The membranes prepared from these polymers were investigated for their gas permeability for four different gases CH 4 , N 2 , O 2 and CO 2 . The PA membranes showed high gas permeability ( P CO2 up to 81 and P O2 up to 20 barrer) and high permselectivity ( P CO2 / P CH4 up to 47.50 and P O2 / P N2 up to 6.9). The gas transport properties have been correlated with the polymer structures and fractional free volume (FFV).

A series of new aromatic polyamides (PAs) containing 1-adamantanemethoxy substituted triphenylamine has been synthesized for the membrane based gas separation. The PAs were readily soluble and cast into flexible membranes (tensile strengths ~104 MPa). All the membranes showed high thermal stability (440 °C P CO 2 =61.5 and P O 2 =14.2, P CO 2 / P CH 4 =51.25 and P O 2 / P N 2 =10.14). The gas transport properties have been correlated with the polymer structures with respect to their glass transition temperature, fractional free volume (FFV) and dielectric constant values. FFV and free volume distribution were also calculated by the molecular simulation to understand the gas transport properties of the PAs.

In the search for advanced positive pseudocapacitive electrode material for potential application to practical energy storage and conversion devices, innovative design and alteration of the assemblage of the complex transition metal oxide based core-shell heterostructures are technically highly essential undertakings. Herein, uniquely assembled three-dimensional porous Zn-Ni-Co oxide (ZNCO)@NiMoO4 core-shell nanowire/nanosheet arrays (NWNSAs) supported on Ni foam as integrated pseudocapacitive electrode are fabricated for the first time by a facile and scalable two-step hydrothermal process combined with post-annealing methods. Taking advantage of the synergistic interaction in core-shell architecture, the hierarchical porous ZNCO@NiMoO4 NWNSAs offers excellent conductivity, durability, effective nanoporous network, and proper channels for the rapid transfer of ions/electron for reversible Faradaic reaction. In a three-electrode assembly, the hierarchical as-synthesized ZNCO@NiMoO4 electrode exhibits higher specific capacity (CS; 338.5 mA h g−1 at 3 mA cm−2), rate performance (71% up to 25 mA cm−2), and good cyclic stability (86% capacity retention after 10,000 cycles) than the ZNCO electrode (CS; 266.1 mA h g−1 and 57% up to 25 mA cm−2). The all-solid-state asymmetric supercapacitor (ASC) device consisting of ZNCO@NiMoO4 NWNSAs as cathode and Fe2O3/graphene hydrogel as anode electrodes shows superior specific capacity (87.5 mA h g−1 at 4 mA cm−2), high rate capability (50.5% up to 50 mA cm−2), excellent life-span (91% after 10,000 GCD cycles), and very high energy and power densities (~70 W h kg−1 and 5115.1 W kg−1), suggesting its potential applicability to advanced hybrid supercapacitors.

Polyamide-tethered polyhedral oligosilsesquioxane (POSS) nanocomposites (PAMIP) with well-defined architectures have been synthesized through Michael addition reaction between the maleimide-containing fluorinated new copolyamides (PAMI) with amino-functionalized POSS (POSS-NH2) nanofiller. The chemical structures of the polyamide–POSS nanocomposites were characterized by 1H NMR and Fourier transform infrared spectroscopy. The effects of POSS-NH2 on the morphology and properties of the PAMIP membranes were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction and transmission electron microscopy (TEM) analysis. POSS molecules tethered to polyamide form sphere shaped POSS aggregate cages (phase separated morphology) were confirmed by TEM analysis. All the PAMIP membranes showed very high permeability for different gases compared to PAMI membranes. The increase in permeability is accompanied by increase in diffusivity coefficient of the PAMIP membranes for d...

In this work we report the synthesis of a new diamine monomer, 1-adamantylmethyl[3,5-bis-{2′-trifluoromethyl-4′-(4″-aminophenyl)phenoxy}]benzoate and its polymerization with four different diacids. The monomer and the prepared poly(ether amide)s (PAs) were characterized by elemental analyses, NMR, and FTIR techniques. The polymers were further characterized by GPC and thermal techniques and the mechanical properties of the films prepared from these polymers are also reported. The permeability of CH4, N2, O2 and CO2 through these PA membranes was investigated at three different temperatures (35, 45 and 55 °C) under an applied upstream pressure of 3.5 bar. The PA 9B containing hexafluoroisopropylidene moiety exhibited highest permselectivity in the series (for, O2/N2=8.2 and CO2/CH4=41.7) whereas PA 9A containing tert-butyl moiety exhibited highest gas permeability ( P CO 2 =34 and P O 2 =9.5). The gas transport properties have been correlated with the polymer structures with respect to their glass transition temperature, chain packing and dielectric constant values. The activation energies of the permeation and diffusion processes were calculated.

This article describes the synthesis, characterization and gas transport properties of a series of new fluorinated poly(arylene ether)s (PAE)s, prepared from 4,4′-cyclohexylidenebisphenol on reaction with five structurally different aromatic bisfluoro monomers. The PAEs were characterized by elemental analyses, NMR, FTIR, GPC and thermal techniques. The polymers showed high T g (up to 231 °C), outstanding thermal stability (up to 516 and 495 °C in nitrogen and air respectively), high tensile strength (up to 73 MPa) and low dielectric constant ( ∊ = 2.31). Gas transport properties of these PAE membranes were investigated at three different temperatures using the four different gases (e.g., CH 4 , N 2 , O 2 and CO 2 ). The effect of cardo cyclohexylidene unit in the PAE membranes on gas transport properties has been investigated. The PAEs in this investigation showed high gas selectivity [ α (CO2/CH4) = 44.85] and comparable permeability with many other previously reported poly(arylene ether)s.

A series of processable fluorinated poly(ether imide)s (PIs) were synthesized by reacting a diamine monomer, 1,4-bis-[{2′-trifluromethyl 4′-(4″-aminophenyl)phenoxy}] benzene (HQA) with six different aromatic dianhydrides e.g., BPADA, 6FDA, ODPA, BPDA, BTDA and PMDA. The polyimides showed reasonably high glass-transition temperature ( T g up to 280 °C) and high thermal stability ( T d,10 up to 558 °C). The membranes of these polymers showed tensile strength up to 107 MPa with elongation at break up to 15%, low water absorption (0.61–1.29%), low dielectric constant (2.10–3.13 at 1 MHz) and high optical transparency ( λ cut-off up to 466 nm). The PI membrane prepared from 6FDA exhibited high permeability and permselectivity for O 2 /N 2 ( P O2 = 11.8 and P O2 / P N2 = 9.44) gas pair which eventually surpassed the present upper boundary limit drawn by L.M. Robeson.

This manuscript describes the synthesis, characterization and gas transport properties of a series of poly(ether amide)s (PAs) prepared from a new diamine monomer 4,4-bis-[2′-trifluromethyl 4′-(4″-aminophenyl)phenoxy]-biphenyl on reaction with five different aromatic dicarboxylic acids. The polyamides exhibited very good film forming ability, thermal and mechanical properties (448–479 °C for 10% weight loss in air, glass transition temperatures in the ranges of 252–278 °C, tensile strengths up to 99 MPa). PA ‘I’ having tert-butyl group showed highest permeability in barrer for PCO2 = 42.60, PO2 = 10.00, PN2 = 2.10, PCH4 = 1.80. PA ‘II’ containing hexafluroisopropylidene linkage showed highest permselectivity for O2 and N2 gas pair (PO2/PN2 = 7.08) whereas PA ‘IV’ showed highest permselectivity towards CO2 over CH4 (PCO2/PCH4 = 30.25) among the series. Attempt has been made to draw structure–property co-relationship in terms of thermal, mechanical and gas transport properties vs. the polymer repeat unit structures.

The gas permeabilities of CH4, N2, O2 and CO2 through a series of poly(arylene ether)s (PAEs) containing cardo phthalimidine unit in the main chain were measured at three different temperatures and fixed gas pressure of 3.5 bar. The polymers exhibited high permeabilities and moderate selectivities. Two of the polymers named PAE-II and PAE-III showed high permeability for all the gases (PCO2 = 44.04, 40.06 Barrers, respectively). Moreover, high permeability coefficients for O2 (PO2 = 12.37–7.41) with good permselectivities towards O2 and N2 (8.14–6.92) made these series of poly(arylene ether)s highly interesting in comparison to the previously reported phthalimidine based polymers. The temperature dependence of permeability/diffusion coefficients enable to calculate the activation energies for the permeation/diffusion process of different gases through these membranes. An attempt has been taken to establish structure–property correlationship between the repeat unit structures and the gas transport properties of these polymers.

A series of semifluorinated aromatic poly(ether amide)s (PA) were prepared from a new diamine; 1,1-bis-[4′-{2″-trifluromethyl 4″-(4″′-aminophenyl)phenoxy}phenyl]cyclohexane with five structurally different aromatic diacids. The PAs were characterized by elemental analysis, NMR, FTIR, GPC and thermal techniques. The polymers exhibited very good thermal and mechanical properties (441 °C for 10% weight loss in air, glass transition temperatures ranging from 239 to 258 °C and tensile strengths up to 86 MPa). Gas transport properties of these membranes were investigated for the four different gases (e.g., CH 4 , N 2 , O 2 and CO 2 ). These membranes showed good gas selectivity with comparable permeability with previously reported aromatic polyamides. PA ‘ 6A ’ showed high CO 2 and O 2 permeability (30.40 and 6.30 Barrer respectively) and PA ‘ 6E ’ showed high permselectivity for CO 2 /CH 4 (64.29) and O 2 /N 2 (10.67) gas pair. The effect of the presence of the cardo cyclohexylidene unit in the PA membranes towards the thermal, mechanical and gas permeation properties were correlated.

A series of processable fluorinated poly(ether amide)s (PAs) were synthesized from a new diamine monomer, 1,4-bis-[{2′-trifluromethyl 4′-(4″-aminophenyl)phenoxy}] phenyl with four different aromatic dicarboxylic acids. The polymers have been well characterized by GPC, FTIR, NMR, XRD and thermal techniques. The PAs showed excellent thermal stability (411–468 °C for 10% weight loss), high glass transition temperatures (243–290 °C), high tensile strengths up to 83.9 MPa and elongation at break up to 21%. PA ‘6a’ showed highest permeability in barrer for P CO 2 = 55.41 , P O 2 = 14.09 , P N 2 = 2.38 , P CH 4 = 2.29 . PA ‘6b’ showed highest permselectivities for CO2 and CH4 ( P CO 2 / P CH 4 = 36.83 ) as well as for O2 and N2 gas pairs ( P O 2 / P N 2 = 8.05 ) among the series. It has been attempted to draw a structure–property correlationship between the chemical structures of the polymers and their gas transport properties on the basis of their FFV, glass transition temperatures, and chain packing density.

Aromatic polyamides are a class of high-performance polymers. However, their insolubility and processing difficulty has restricted their applications. Fluorinated polyamides exhibit enhanced solubility in common organic solvents. Additionally, fluorinated polyamides show improved properties in comparison to the nonfluorinated analogs. This chapter describes the synthesis, properties, and applications of the fluorinated polyamides. The first part deals with the general synthetic procedure of aromatic polyamides. The structural modification and properties of the fluorinated polyamides are discussed thereafter. Finally, the use of these fluorinated polyamides in different membrane-based applications such as in gas permeation and pervaporation and as a proton exchange membrane in fuel cell application has been discussed.

A series of new semifluorinated sulfonated polyimide copolymers (DHNHXX) were prepared from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), 4,4′-diaminostilbene-2,2′-disulfonic acid (DSDSA) and 1,4-bis-[{2′-trifluoromethyl-4′-(4′′-aminophenyl)phenoxy}] benzene (HQA). The degree of sulfonation of DHNHXX was varied by changing the molar ratio of the sulfonated diamine, DSDSA to the non-sulfonated diamine, HQA. The flexible DHNHXX membranes showed high thermal stability (desulfonation temperature above 270 °C) and good mechanical properties. The oxidative stability of DHNHXX improved with increasing the fluorine content. DHNHXX showed anisotropic dimensional changes, and good water stability (did not dissolve for up to 415 h), higher than many other sulfonated polyimides. Transmission electron microscopy (TEM) analysis revealed cluster-like microstructures for the DHNHXX membranes, suggesting good phase-separated morphology. DHNH70 with IEC = 2.10 meq. g−1 exhibited high proton conductivity, with a maximum up to 129 mS cm−1 at 90 °C in water.

Here we report the synthesis and properties of a series of processable poly(ether amide)s (PAs) having the bis(phenylphenyl)fluorene moiety prepared from a new diamine monomer, 9,9-bis-[3-phenyl-4-{2′-trifluoromethyl-4′-(4′′-aminophenyl) phenoxy}phenyl]fluorene. Analogous PAs having the bis(phenyl)fluorene moiety have also been prepared from the diamine 9,9-bis-[4-{2′-trifluoromethyl-4′-(4′′-aminophenyl) phenoxy} phenyl]fluorene for comparative purposes. The synthesized PAs exhibited high thermal stability (up to 517 °C and 539 °C in air and nitrogen respectively, for 10% weight loss), high glass transition temperature (272–299 °C) and high tensile strength up to 117 MPa. The optically transparent membranes (λcut-off ≥ 368 nm) from these PAs showed high gas permeability in barrer (PCO2 up to 67.42 and PO2 up to 15) and high permselectivity (PCO2/PCH4 up to 88.37 and PO2/PN2 up to 10.84); especially for the O2/N2 gas pair the PAs surpass or touch the present upper boundary limit of 2008 drawn by Robeson. The effect of the bis(phenylphenyl)fluorene moiety and diacid moieties in PAs on the dielectric values, thermal, mechanical, optical and gas transport properties were correlated.