A series of mixed matrix membranes based on zeolites incorporated into fluorinated polyimides were fabricated and characterized in this study. The first system consisted of a polyimide (6FDA-6FpDA-DABA) with carboxylic acid groups incorporated into its backbone and amine-functionalized zeolite particles (ZSM-2). FTIR indicated that these functional groups interacted with each other through hydrogen bonding. Both SEM and TEM images revealed good contact between the polyimide and the zeolite. Permeability studies showed a drop in He permeability suggesting there were no voids between the two components. While simple gases such as O2 and N2 followed effective permeabilities predicted by mixing theories, polar gases such as CO₂ did not. The second system fabricated used the same polyimide with amine-functionalized zeolite L. This zeolite differs from ZSM-2 in that zeolite L's pores are not clogged with an organic template, and it possesses 1-D pores as opposed to ZSM-2's 3-D pore structure. XPS and zeta potential experiments were performed to verify the presence of amine groups on the zeolite surfaces. FTIR data showed that after a heat treatment, amide linkages were created between the amine group on the zeolite and the carboxylic acid group of the polyimide. SEM images showed a good distribution of zeolite L throughout the polymer matrix, and no indication of voids between the two components. Permeability experiments were performed to determine if the addition of zeolite L to the polyimide improved its separation performance. The permeability was unchanged between the pure polyimide membrane and the mixed matrix membrane, suggesting there were no voids present within the matrix. Permeability results of larger gases followed a Maxwell Model. A third system was prepared using a poly(imide siloxane) (6FDA-6FpDA-PDMS) and untreated zeolite L. The primary focus of this investigation was to determine if the addition of the flexible segment would promote direct contact with the zeolite surface and remove the need to amine-functionalize the zeolite. Poly(imide siloxane)s were synthesized at 0, 22, and 41 wt % PDMS as verified using 1H-NMR. FTIR was employed to qualitatively verify the successful imidization of the polymers. SAXS patterns and TEM images did not reveal distinct phases indicative of phase separation, however, AFM images did show the presence of phase separation of the surfaces of the poly(imide siloxane)s. Permeability results showed a decrease in selectivity and an increase in permeability as the wt % of PDMS was increased. Permeabilities and selectivities dropped as the zeolite loading was increased from 0 to 20 wt %. Upon increasing the zeolite loading from 20 to 30 wt %, increases in permeability were observed, but both the permeability and selectivity were still below that of the pure polymer. The final system studied employed the 41 wt % PDMS poly(imide siloxane) as the polymer matrix and either closed-ended or open-ended carbon nanotubes as the filler. SEM images showed regions of agglomeration for both types of nanotubes. Helium permeability dropped in both types MMMs, but more so in closed-ended carbon nanotubes MMM. Nitrogen permeability was unchanged for the closed-ended carbon nanotubes MMM, and dropped slightly in the open-ended carbon-nanotube MMM. / Ph. D.

Research is presented on the crystallization and melting behavior of an aromatic semi crystalline polyimide known as LaRC CPI - 2 (Langley Research Center Crystalline rolyimide - second generation). This aromatic polyimide, a structural variant of the well known LaRC CPI, is synthesized froml 1,4-bis( 4-aminophenoxy-4' -benzoyl)benzene (1,4-BABB) and 4,4' -oxydiphthalic dianhydride (ODPA). The multiple melting behavior at ca. 334°C and 364°C, characteristic of this polymer, is analyzed and explained. Transmission electron microscopy (TEM), wide angle X-ray diffraction (W AXD), and small angle X-ray scattering (SAXS) studies, in conjunction with differential scanning calorimetry (DSC) analysis, show that the high melting transition results from the melting of lamellae which were melt recrystallized during heating in a DSC. The effects of synthesis and process variables upon the crystallization and melting properties of this polyimide were also studied. The DSC response of LaRC CPI - 2 films and powders of varying molecular weight are compared and contrasted. Powders generally melt at a higher temperature than films of the same molecular weight. The glass transition temperature, T g' of both the powders and films are found to be dependent upon molecular weight. An interpolated value of T g for the infinite molecular weight LaRC CPI - 2 is ca. 234°e. In a study of the development of crystallinity in films during standard thermal imidization, crystallinity was found to initiate off the glass surface very early in the process leaving an amorphous layer at the air surface after the full thermal treatment. LaRC CPI - 2 powder 'types' synthesized in different solvents, dimethylacetamide (DMAc) and m-cresol present with dramatically different melting, melt stability and crystallization properties. Though the chemical architecture and crystal lattice structure are the same, the powders synthesized in DMAc display dual melting transitions at ca. 334°C and 364°C, while the powders from m-cresol melt singularly at ca. 409°C. Rheological analysis, along with annealing data, revealed a higher temperature melt stability in the powders from m-cresol. It is postulated that the differences in the properties of the two powders are the result of differing initial molecular weights and a suppression of a cross-linking ketimine reaction in the polymer produced in m-cresol. / Ph. D.

The objective of this study was to examine the effects of annealing polyimide-organosilicate hybrid membranes on gas transport. In addition, the effects of carbon dioxide pressure on the gas transport of unannealed polyimide-organosilicate hybrid membranes were evaluated. The membranes in both studies consisted of sol-gel derived organosilicate domains covalently bonded to a 6FDA-6FpDA-DABA polyimide using partially hydrolyzed tetramethoxysilane (TMOS), methyltrimethoxysilane (MTMOS) or phenyltrimethoxysilane (PTMOS). The first study subjected the hybrid membranes to a 400°C annealing process to enhance gas separation performance by altering the organosilicate structures. The hybrid membranes were evaluated before and after annealing using pure gases (He, O₂, N₂, CH₄, CO₂) at 35°C and a feed pressure of 4 atm. The permeability for most of the membranes increased 200-500% after the annealing process while the permselectivity dropped anywhere from 0 to 50%. The exceptions were the 6FDA-6FpDA-DABA-25 22.5 wt% TMOS and MTMOS hybrid membranes, both of which exhibited increases in the CO₂ permeability and CO₂-CH₄ permselectivity. The increase in permeation was attributed to increases in the free volume and enhanced segmental mobility of the chain ends resulting from the removal of sol-gel condensation and polymer degradation byproducts. For the second study, the transport properties of four membranes, 6FDA-6FpDA polyimide, 6FDA-6FpDA-DABA polyimide, MTMOS and PTMOS-based hybrid materials, were characterized as a function of feed pressure to evaluate how the hybrid materials reacted to CO₂ plasticization. Steady-state gas permeation experiments were performed at 35°C using pure CO₂ and CH₄ gases at feed pressures ranging from 4 to 30 atm. All four materials exhibited dual mode sorption up to feed pressures of 17 atm, at which point the effects of CO₂ plasticization were observed. / Master of Science

Les assemblages multicouches polymère-métal, combinant la faible densité du polymère à la résistance du métal, se présentent comme une solution à fort potentiel pour répondre aux problématiques d’allégement de structure dans le secteur des transports. Plus particulièrement, ces travaux s’intéressent à l’élaboration de multicouches basés sur l’utilisation de polymères thermoplastiques thermostables associés à un alliage d’aluminium via un procédé de la métallurgie des poudres appelé « Spark Plasma Sintering » (SPS). Dans un premier temps, la mise en forme par SPS du polymère seul a été étudiée. Les influences des paramètres SPS tels que la température, la pression appliquée et le temps de maintien sur les caractéristiques structurales et les propriétés mécaniques du polyétheréthercétone (PEEK) ont été déterminées au moyen d’un plan d’expérience. Cette étude a permis de proposer des mécanismes de frittage et de mettre en évidence le rôle complexe joué par la pression sur la structure cristalline. Ensuite, le développement des assemblages, sans colle, d’un polyimide ou PEEK associé avec l’aluminium a été considéré. Une approche expérimentale a été mise en place, dans le but d’améliorer l’adhésion entre les deux matériaux. Des traitements de surface appliqués à l’aluminium visant à augmenter l’ancrage mécanique et la compatibilité chimique ont été testés. Le renforcement du polymère afin de limiter sa dilatation thermique a également été abordé. Les contributions de chacun des facteurs sont discutées sur la base de mesures d’adhérence et de caractérisations microstructurales. Cette stratégie a permis d’obtenir des multicouches avec une forte résistance à l’interface. / Polymer/metal multilayer assemblies, combining the low density of the polymer with the strength of the metal, are considered to be of great interest for high-demand engineering applications, especially in the transportation industries where the lightweighting issues are predominant. Keeping this in mind, the present study deals with the development of this kind of assembly, using thermostable thermoplastic polymers associated with an aluminum alloy by means of a powder metallurgy process: the “Spark Plasma Sintering” (SPS) technology. As the first part of this work, the sintering of the polymer was considered. The effects of SPS parameters such as temperature, pressure, and dwell time on mechanical properties of a PolyEtherEtherKetone (PEEK) were investigated thanks to a design of experiment. This study allowed to determine the mechanisms of polymer’s consolidation and the intricate role of pressure on the PEEK crystallinity was examined with particular attention. Then, the development of the assembly, without adhesive part, composed of both polymer (polyimide or PEEK) and aluminum alloy was considered. An approach was set up to improve the compliance between these dissimilar materials comprising: surface treatments on aluminum in order to enhance their mechanical anchoring and their chemical compatibility, as well as polymer reinforcement with the aim of reducing its thermal expansion. The efficiency of each solution is discussed based on microstructural and mechanical characterizations. This approach enabled to process multilayer assemblies with a significant strength at the interface.

The humidity, temperature, wind speed/direction micro sensors can be manufactured individually, resulting in three individual substrates. The integration of the three sensors into a single substrate is a vital challenge to achieve an integrated intelligent sensor so called a multiple sensor. This requires the integration of process flows and is a major challenge because adequate sensor performance must be maintained. Polyimide was selected as a humidity sensing material for its compatibility with conventional integrated circuit fabrication technology, negligible temperature dependence and good resistance against contamination. Nickel was selected for the temperature and wind speed/direction sensor because of its useful temperature coefficient and the advantage of its cost. Since the known wet etchant for nickel requires hard-baked photoresist, a method which does not attack the polyimide while removing the photoresist must be developed. The method developed for etching nickel employs hard-bake-free photoresist. Other challenge was ensuring good thermal isolation for the wind speed/direction sensor fabricated on a silicon nitride layer preformed on top of a silicon wafer. Since silicon acts as a good heat sink, the silicon under the sensor was etched entirely away until the silicon nitride layer was reached. This structure achieved good thermal isolation resulting in small power consumption. This low power feature is essential for sensors deployed in fields where power access or replacement of power sources is restricted. This structure was compared with the structure created by polyimide plateau on a silicon nitride layer coated on a silicon substrate as a function of power consumption. Based on the examination of thermal isolation, the multiple sensor utilizing a MEMS technique was fabricated with a single-sided mask aligner. The characteristics of humidity sensors fabricated with polyimide were examined in detail with respect to variations of electrode structures, improvement of sensitivity, effect of process temperature, temperature and frequency dependence, and stability. The humidity sensor constructed with O2 plasma treated polyimide resulted an improvement in sensitivity and hysteresis. The investigation using XPS, FTIR and AFM concluded the chemical modification of polyimide played an important role in this improvement. The design, fabrication and results of a series of humidity sensors are quantified. There is always no unique packaging solution for sensors because of the application-specific nature of the sensors. This intelligent environmental monitoring system was designed to accommodate both an environmental sensor and its signal conditioning electronics circuitry (SICONEC) into a single package. The environmental sensors need direct exposure to the environment while SICONEC needs a sealed encapsulation to avoid environmental damage. A new style of packaging addressing these requirements was demonstrated using a hot embossing machine. The hot embossing machine was used to embed an integrated circuit (IC) in a bare die condition into a polycarbonate (PC) sheet. In this case, the IC was flipped down against the PC, which protects the front side of the IC from the environmental damages. In a test phase, a die containing operational amplifiers was embossed into the PC. A humidity sensor and surface mount resisters were placed on the same surface of the PC to test the validity of this new technique. Interconnection between the embossed die and the humidity sensor was established using bonding wires. Copper tracks were also used to ensure all electrical connections for the die, the humidity sensor and the resistors. The results clarified the method developed. Details of process methods, issues and further potential improvement are reported.

Chronic diseases can often be managed by constantly delivering therapeutic amounts of drug for prolonged periods. A controlled release for extended duration would replace the need for multiple and frequent dosing. Local drug release would provide added benefit as a lower dose of drug at the target site will be needed as opposed to higher doses required by whole body administration. This would provide maximum efficacy with minimum side effects. Nonetheless, a problem with the known implantable drug delivery devices is that the delivery rate cannot be controlled, which leads to drug being released in an unpredictable pattern resulting in poor therapeutic management of patients. This dissertation is the result of development of an implantable drug delivery system that is capable of long-term zero order local release of drugs. The device can be optimized to deliver any pharmaceutical agent for any time period up to several years maintaining a controlled and desired rate. Initially significant efforts were dedicated to the characterization, biocompatibility, and loading capacity of nanoporous metal surfaces for controlled release of drugs. The physical characterization of the nanoporous wafers using Scanning electron microscropy (SEM) and atomic force microscopy techniques (AFM) yielded 3.55 x 10⁴ nm³ of pore volume / μm² of wafer surface. In vitro drug release study using 2 - octyl cyanoacrylate and methyl orange as the polymer-drug matrix was conducted and after 7 days, 88.1 ± 5.0 % drug was released. However, the initial goal to achieve zero order drug release rates for long periods of time was not achieved. The search for a better delivery system led to the design of a perforated microtube. The delivery system was designed and appropriate dimensions for the device size and hole size were estimated. Polyimide microtubes in different sizes (125-1000 μm) were used. Micro holes with dimensions ranging from 20-600 μm were fabricated on these tubes using photolithography, laser drilling, or manual drilling procedures. Small molecules such as crystal violet, prednisolone, and ethinyl estradiol were successfully loaded inside the tubes in powder or solution using manual filling or capillary filling methods. A drug loading of 0.05 – 5.40 mg was achieved depending on the tube size and the drug filling method used. The delivery system in different dimensions was characterized by performing in vitro release studies in phosphate buffered saline (pH 7.1-7.4) and in vitreous humor from the rabbit’s eye at 37.0 ± 1.0°C for up to four weeks. The number of holes was varied between 1 and 3. The tubes were loaded with crystal violet (CV) and ethinyl estradiol (EE). Linear release rates with R²>0.9900 were obtained for all groups with CV and EE. Release rates of 7.8±2.5, 16.2±5.5, and 22.5±6.0 ng/day for CV and 30.1±5.8 ng/day for EE were obtained for small tubes (30 μm hole diameter; 125 μm tube diameter). For large tubes (362-542 μm hole diameter; 1000 μm tube diameter), a release rate of 10.8±4.1, 15.8±4.8 and 22.1±6.7 μg/day was observed in vitro in PBS and a release rate of 5.8±1.8 μg/day was observed ex vivo in vitreous humor. The delivery system was also evaluated for its ability to produce a biologically significant amounts in cells stably transfected with an estrogen receptor/luciferase construct (T47D-KBluc cells). These cells are engineered to produce a constant luminescent signal in proportion to drug exposure. The average luminescence of 1144.8±153.8 and 1219.9±127.7 RLU/day, (RLU = Relative Luminescence Units), yet again indicating the capability of the device for long-term zero order release. The polyimide device was characterized for biocompatibility. An automated goniometer was used to determine the contact angle for the device, which was found to be 63.7±3.7degreees indicating that it is hydrophilic and favors cell attachment. In addition, after 72 h incubation with mammalian cells (RAW 267.4), a high cell distribution was observed on the device’s surface. The polyimide tubes were also investigated for any signs of inflammation using inflammatory markers, TNF-α and IL-1β. No significant levels of either TNF-α or IL-1β were detected in polyimide device. The results indicated that polyimide tubes were biocompatible and did not produce an inflammatory response. / text

Carbon fiber (CF) 8-harness satin weave, T650/Neximid system of [(+45/-45)/(0/90)]2S and [(0/90)]4S layup was manufactured using resin transfer molding (RTM). The material was cut into 3-point bending specimens and treated for 24 hours in a burn oven at T=(320,350,375,400,450 & 500)°C. The material was tested according to ASTM E1640-13 using dynamic mechanical thermal analysis (DMTA). Un-treated material showed Tg levels of 384°C and 392°C for the respective layups. It was found that pre-Tg treatment between 320-375°C affected this material parameter up to similar levels as previous studies of post Tg exposure for 2h to ~420°C [4]. Subjecting the material for post-Tg exposure at 400°C showed a rapid change up to ~480°C for [(0/90)]4S laminate. Indications that this resin system could reach levels above 500°C was found for [(+45/-45)/(0/90)]2S layup. However, one of these specimens were unfit for testing. DMTA tested material for 400°C showed indications of degradation, found by a broadening of the tan delta peak. This can be put in relation to epoxy where a similar behavior appear after 24h exposure at 150°C. Furthermore, it was showed that poor quality laminate, elevated mass loss at this temperature. When the material was subjected to as high temperatures as 450°C only remaining fibers were found. At 500°C these were almost fully oxidized. 400°C data was predicted by the use of activation energy along with TG extrapolation. It was possible to show that ~1/8 out of this 8-layered structure, (½ of each surface layer), was degraded after 400°C exposure for 24h, resulting in diffusion limited oxidation (DLO). Last but not least, DLO assumptions was used to predict the storage modulus change for thermo-oxidative degradation of 400°C samples with Classic Laminate Theory (CLT). A ~4% stiffness decrease was predicted by this method. The drop is regarded as a loss in tensile stiffness of the outer damaged layer. This was compared by 3-point bending DMTA data showing a ~7% decrease. This model could thus be regarded as a contributing factor for the stiffness decrease of this complex degradation process. / Kolfiber, 8-harness satin väv, T650/NEXIMID system med [(+45/-45)/(0/90)]2S och [(0/90)]4S orientering, tillverkades via RTM. Från materialet tillverkades 3-punkts böjprover. Dessa behandlades i 24 timmar vid T=(320, 350, 375, 400, 450 & 500)°C, i en brännugn. Materialet testades i enighet med ASTM E1640-13 via DMTA. Obehandlat material visade Tg nivåer av 384°C och 392°C för de respektive uppläggningarna. Pre-Tg exponering, vid 320-375°C, påverkade Tg upp till liknande nivåer som tidigare studier, (post-Tg 2h), ~420°C [4]. När materialet utsätts för post Tg exponering under 24 timmar vid 400°C kunde man se en snabb förändring av Tg, upp till ~480°C för [(0/90)]4S laminatet. Från [(+45/-45)/(0/90)]2S laminatet kunde man dessutom se indikationer på att nivån kunde nå över 500°C. Däremot var en av dessa prov inte kvalificerad för test efter behandlingen. DMTA testat material för 400°C visade indikationer av nedbrytning, via en breddning av piken för tan-delta kurvan. Det var dessutom möjligt att se att laminat av sämre kvalitet påverkade viktminskningen signifikant högre vid denna exponering. När material utsattes för så höga temperaturer som 450°C var endas fiber kvar efter test, vilket vid 500°C nästan var fullt nedbrutna. 400°C data förutspåddes via extrapolering av TG och Arrhenius beräkning. Beräkningen ledde till en övre gräns för nedbrytningen. Vidare var det möjligt att visa att ~1/8 av dessa 8-lager bröts ner efter 24 timmars exponering vid 400°C. Nedbrytningen motsvarar ½ av vartdera ytlager via diffusions begränsad oxidation (DLO). Sist men inte minst, kunskapen om DLO användes för att förutspå styvhetsförändringen vid termo-oxiderande nedbrytning med hjälp av klassisk laminat teori (CLT). DLO antogs resultera i en volymfraktionsförändring i det yttersta lagret. Detta implementerades i CLT där man kunde beräkna en ~4% styvhetsminskning via denna modell där det yttre skadade lagret har en reducerad dragstyvhet. Från testade böjprover i DMTA kunde man se en verklig ~7% styvhetsminskning för samma exponeringsvillkor. Modellen kan därmed ses som en bidragande del av denna komplexa nedbrytningsprocess.

The thesis comprises the two parts in each chapter: the first part focuses on the development and characterization of polyimide (PI) based composite coatings on a steel substrate. In order to improve the tribological performance of polyimide coatings, the fillers i.e. multi-walled carbon nanotubes (MWCNTs) and Graphene (GP) were added into PI and conducted friction test at elevated temperatures ranging from room temperature (RT) to 200°C. Also, the influence of fillers (MWCNTs and GP) materials into PI coatings surface, mechanical and tribological properties of polyimide composites coatings are measured. The addition of MWCNTs and GP reduces the friction coefficient as well as wear volume at elevated temperatures 50°C, 100°C and sometimes at 150°C. These temperatures play a vital role to form a lubrication layer in the contact interfaces at certain load and operating conditions. In these cases, three weight percentage (3wt%) of MWCNTs and GP into polyimide composites showed low friction and high wear-resistant as compared to other PI composites. Besides, by adding these two fillers into pure PI improved the mechanical properties such as micro-hardness and nanoindentation. The scanning electron microscope (SEM) was used to observe the wear mechanism of the composite coatings worn surfaces. The consequences expose that the fatigue wear mechanisms were predominant in the worn surfaces. Moreover, the thermal study of the polyimide composite coatings was conducted using thermal gravimetric (TG) to analyze the behavior of composite coatings at high temperatures. The results showed that the PI coatings with MWCNTs and GP have high thermal stability at 60% sample residue. In the second part-an epoxy coatings with filler materials e.g. hexagonal boron nitride (h-BN) and expanded graphite (EG) were made and conducted their tribological i.e. friction coefficient and wear performance. Also the perfect mixing ratio 4:1 (80 wt% base epoxy matrix and 20 wt% curing agent) was determined on the basis of stoichiometric ratio to cure the epoxy accurately. Therefore, seven samples with a various weight percentage (wt%) were prepared i.e. pure epoxy, epoxy with 5wt%, 10wt%, 15wt% of h-BN and EG. All the prepared samples ran at two different loading 2 N and 4 N conditions with 5 Hz frequency, 300 rpm and 30 minutes duration. The epoxy with h-BN showed low friction as compared to EG where EG has better wear-resistant behavior than h-BN.

Ce travail a consisté à synthétiser un matériau hybride polyimide/silice par voie Sol-Gel. La préparation de ces matériaux pose un problème de compatibilité entre les phases organique et inorganique. La silice et le polymère n'ont pas d'affinité particulière et ont tendance à créer une forte ségrégation de phase. Pour éviter ce phénomène plusieurs solutions ont été reportées dans la littérature, comme l'utilisation d'agent de couplage. Dans notre cas, nous avons réduit ce phénomène en créant des liens covalents entre le Celles-ci vont réagir avec la silice lors du procédé Sol-Gel. Nous avons fait varier différents paramètres tels que le taux de greffage entre les phases, ou le catalyseur utilisé lors du procédé Sol-Gel. La suite du travail a consisté à étudier les différentes morphologies obtenues en fonction de l'évolution des paramètres de synthèse. Pour cela, nous avons utilisé différentes techniques tel que l'analyse thermogravimétrique, la détermination de densité, la spectroscopie infrarouge, ou la microscopie. Ce travail nous a permis de déterminer les taux de silice, la taille des particules au sein de la matrice et leur état de dispersion. Nous avons également étudié la microstructure de nos matériaux par spectroscopie mécanique dynamique. En effet, les différentes morphologies conduisent à des effets sur le renforcement de la phase silice sur les propriétés mécaniques de nos matériaux. Nous avons ainsi pu identifier des phénomènes de percolation pour certains de nos matériaux. Dans un dernier temps, nous avons étudié les propriétés de perméation gazeuse de nos matériaux, afin de tirer les grandes évolutions des coefficients de perméabilité et de sélectivité en fonction du taux de silice et du taux de greffage entre la phase organique et inorganique. Nous avons ainsi montré que l'introduction de la silice et le greffage de celle-ci avec le polymère conduisaient à des matériaux moins perméable, mais généralement plus sélectif.

<p>South Africa s coal and platinum mineral resources are crucial resources towards creating an alternative and environmentally sustainable energy system. The beneficiation of these natural resources can help to enhance a sustainable and effective clean energy base infrastructure and further promote their exploration and exportation for economics gains. By diversification of these resources, coal and the platinum group metals (PGMs) especially palladium market can be further harnessed in the foreseeable future hence SA energy security can be guaranteed from the technological point of view. The South Africa power industry is a critical sector, and has served as a major platform in the South African socio-economic development. This sector has also been identified as a route towards an independent energy base, with global relevance through the development of membrane technologies to effectively and economically separate and purify hydrogen from the gas mixtures released during coal gasification. The South Africa power industry is a critical sector, and has served as a major platform in the SA&rsquo / s socio-economic development. This sector has also been identified as a route towards an independent energy base, with global relevance through the development of membrane technologies to effectively and economically separate and purify hydrogen from the gas mixtures released during coal gasification. Coal gasification is considered as a source of hydrogen gas and the effluent gases released during this process include hydrogen sulphide, oxides of carbon and nitrogen, hydrogen and other particulates. In developing an alternative hydrogen gas separating method, composite membrane based on organic-inorganic system is being considered since the other available methods of hydrogen separation are relatively expensive.<br /> &nbsp / </p>