Interpenetrating Network Membranes Research Articles

Tuning Polybenzimidazole‐Derived Crosslinked Interpenetrating Network Membranes for Vanadium Redox Flow Batteries

AbstractNon‐fluorinated ion exchange membranes with high proton selectivity and conductivity are sought as separators for vanadium redox flow batteries (VRFB) to substitute the typically used perfluorosulfonic acid (PFSA) polymer membranes. Polybenzimidazole based membranes offer a promising non‐fluorinated alternative due to their excellent thermomechanical properties, low vanadium crossover, and ionic conductivity in acidic media. In this work, a series of polybenzimidazole‐polyvinylchloride polymer blends were cast and decorated with different quaternary ammonium functionalities. The polymer blends were systematically studied with respect to the blend composition and chemical structure of the quaternary ammonium groups. Assessment of relevant membrane properties for use in an aqueous acidic flow battery was conducted through a combination of VRFB single cell testing, permeability measurements, water/electrolyte uptake, and infrared spectroscopy. The blend with a polybenzimidazole content of 90 % decorated with DABCO (1,4‐diazabicyclo[2.2.2]octane) was found to combine low polarization resistance with low swelling and high stability. The performance was found to be similar to that of a benchmark polybenzimidazole membrane despite being three times thicker. This led to the conclusion that quaternary ammonium functionalized polybenzimidazole‐polyvinylbenzylchloride systems is an excellent candidate for further modification or fabrication of thinner membranes to further reduce the membrane resistance without compromising on vanadium blocking properties.

Pervaporation separation of chlorinated environmental pollutants from aqueous solutions by castor oil based composite interpenetrating network membranes

Castor oil derived polyurethane (PU)-polydimethylsiloxane (PDMS) blends were synthesized to develop novel composite interpenetrating network (CIPN) membranes for improving the efficiency of pervaporation (PV) in selective removal of toxic chlorinated volatile organic compounds (VOCs) such as dichloromethane (DCM), 1,2-dichloroethane (DCE), 1,1,2-trichloroethane (TCE), and 1,1,2,2-tetrachloroethane (TeCE) from dilute aqueous solutions. Structural characterization of the synthesized CIPN membranes was performed by several analytical methods to evaluate thermal stability, swelling characteristics, extent of cross-linking, crystallinity, surface morphology and mechanical strength. Among the CIPNs of varying compositions, the membrane comprising of 8 wt% PDMS in PU exhibited moderate steady state flux values of 0.183, 0.162, 0.060 and 0.082 kgm−2 h−1 associated with correspondingly high selectivity values of 672, 1415, 10,901 and 19,407 for different feeds containing w/v % concentrations of 1.33% DCM, 0.84% DCE, 0.44% TCE and 0.28% TeCE in water, respectively. The experimental results have demonstrated that the triglyceride derived PU IPNs have influenced the desirable structural properties along with enhancement in perm-selectivity. The development of high-performance CIPN membranes for PV will certainly stand as a preliminary breakthrough for VOCs removal from aqueous media efficiently.

Synthesis of SGO composite interpenetrating network (CIPN) cation exchange membranes: Stability and salt removal efficiency

Current study demonstrate the alternative route for synthesis of interpenetrating network (IPN) type composite cation exchange membranes (CEM) based on PVC-St/DVB with different content sulfonated graphene oxide (SGO) via simple solution casting method. First, the synthesis of GO was confirmed by TEM and XRD analysis. Functional group characterization of GO and SGO was done by using FT-IR spectroscopy. Water content related assets like water uptake, linear expansion ratio, and ion transport properties like: ion exchange capacity, ionic conductivity of composite IPN membranes were evaluated. Ion exchange capacity and ionic conductivity for PM-5 IPN CEM was found to highest with values of 1.76 meq/g and 4.7 × 10−3 S/cm, respectively. Thermal and mechanical stabilities of prepared membrane were characterized by TGA, DSC, DMA and UTM analysis. Composite interpenetrating network cation exchange membranes (IPN CEM) show better thermal and mechanical stability in comparison with virgin membrane. The suitability of synthesized composite IPN membranes towards electro-membrane processes was evaluated against salt removal by electrodialysis for water desalination. Power consumption and current efficiency during salt removal for PM-5 IPN CEM composite membrane was found to be 1.07 kWh/kg and 82% respectively which was superior among the IPN membrane.

Membrane prepared by incorporation of crosslinked sulfonated polystyrene in the blend of PVdF-co-HFP/Nafion: A preliminary evaluation for application in DMFC

Sodium salt of sulfonated styrene (SS) was polymerized in situ within the polymeric blend of PVdF-co-HFP/Nafion. The electrical efficiency of this cross-linked semi interpenetrating network membranes were evaluated for its potential application as a polymer electrolyte membrane in direct methanol fuel cell (DMFC). The characteristic aromatic peaks obtained in the FT-IR spectra confirmed the successful incorporation of SS within the polymeric blend. X-ray diffraction analyses were conducted to determine the presence of crystalline and amorphous domains within the structure of the blend membrane. Water uptake measurements at room temperature indicate that above a threshold value of 20wt% of incorporated SS (S-20), water uptake of the semi-IPN membranes increases up to 24%, with an IEC value equal to Nafion, i.e. 0.8meqg−1. The maximum current density was recorded to be 120mAcm−2 at 0.2V, with a cell efficiency (power density) of 24mWcm−2 at 60°C. In addition, proton conductivity and methanol permeability test results indicate that the prepared membrane S-20 is comparable to that of Nafion-117 membrane.

Sulfonated Poly(ether ether ketone) and Poly(ethylene glycol) Diacrylate Based Semi-Interpenetrating Network Membranes for Fuel Cells

Polymer electrolyte membranes are prepared from novel semi-interpenetrating polymer network material where the sulfonated poly (ether ether ketone) (SPEEK) is the linear polymer and the poly (ethylene glycol) diacrylate (PEGDA) is the cross-linking constituent. The semi-IPN is prepared by in situ polymerization of PEGDA in the presence of sulfonated poly (ether ether ketone). SPEEK is prepared by direct sulfonation of commercial PEEK (Gatone™ 1100) by reported procedures. SPEEK with degree of sulfonation 63% (calculated from FT-NMR) is selected as the base membrane and different semi-IPN membranes were prepared by varying the PEGDA and SPEEK ratio. The degree of sulfonation of SPEEK and the formation of semi-IPN were confirmed by spectroscopy studies. The various semi-IPN membranes were characterized for ion-exchange capacity, water uptake, hydrolytic stability, proton conductivity and thermal stability for evaluating the suitability of these membranes for fuel cells. The proton conductivity of the membranes decreased with increasing PEGDA content. The Semi-IPN membranes exhibited conductivities (30°C) from 0.018 S/cm to 0.006 S/cm. These interpenetrating network membranes showed higher hydrolytic stability than the pure SPEEK membrane. This study shows that semi-IPN membranes based on PEGDA and SPEEK can be viable candidates for electrolyte membranes.

Sorption and permeation studies of tetrahydrofuran–water mixtures using full interpenetrating network membranes

Acrylic acid (AA) and acrylamide (AM) was free radically copolymerized with 5:1 comonomer ratios in the matrix of polyvinyl alcohol (PVOH). Full interpenetrating network polymer (FIPN) was produced by crosslinking PVOH with glutaraldehyde and the copolymer with N′N′ methylene bis acrylamide (NMBA). Three FIPN membranes containing PVOH:copolymer weight ratio of 1:25, 1:5 and 1:75 designated as FIPN25, FIPN50 and FIPN75, respectively, were synthesized. These full IPN membranes were used for pervaporative separation of tetrahydrofuran (THF)–water mixtures over the concentration range of 78–99 wt.% THF in water. Glutaraldehyde crosslinked PVOH membrane was also used for the same study for comparison. Florey–Huggin lattice model and engaged species induced clustering (ENSIC) model were used to explain sorption of permeants in the membranes. Modified solution-diffusion model was used to find diffusion coefficient, plasticization coefficient and coupling coefficients of the penetrants through the membranes. Intrinsic membrane permeability and selectivity of the membranes were also determined. For an azeotropic composition of 94.3 wt.% THF in water the thickness normalized flux and water selectivity obtained from PVOH, FIPN25, FIPN50 and FIPN75 membranes were 3.2, 2.25, 3.45 and 3.6kgmμ/m2h and 15.10, 32.50, 79.34 and 70.43, respectively.

Synthesis and characterization of bis (4-maleimidophenyl) fluorene and its semi interpenetrating network membranes with polyether imide (Ultem ® 1000)

A semi-interpenetrating network (semi-IPN) of bis (4-maleimidophenyl) fluorene (cardo-BMI) and polyether imide (PEI, Ultem ® 1000) was prepared. The structure of bis (4-maleimidophenyl) fluorene and the corresponding semi-IPNs was determined by nuclear magnetic resonance and Fourier transform infrared spectroscopy, respectively. The thermal properties of the cardo-BMI and semi-IPNs were evaluated by thermogravimetry and differential scanning calorimetry. The semi-IPNs exhibited thermal stability up to 480 °C. The morphology of the semi-IPNs was evaluated by scanning electron microscopy. Asymmetric membranes were prepared from the semi-IPN material by the wet phase inversion method. The pure gas permeation properties of the PEI and semi-IPN membranes were evaluated for oxygen (O 2), nitrogen (N 2), carbon dioxide (CO 2) and methane (CH 4) by the constant pressure and variable volume method at an absolute feed pressure of 0.69 MPa at 22 °C. The CO 2/N 2 selectivity of 39.2 ± 3.0 with a CO 2 permeance of 18.3 ± 4.0 GPU of semi-IPN membrane was higher than the PEI membranes (selectivity 21.6 ± 4.1 and CO 2 permeance 0.5 ± 0.1 GPU). The highest CO 2/CH 4 selectivity of the semi-IPN membrane was 49.3 ± 3.5 compared to 37 for a PEI dense film. Among the semi-IPN membranes, those with 5 wt% cardo-BMI exhibited better performance than the 1% and 10%.

Synthesis of full interpenetrating network membranes of poly(acrylic acid-co-acrylamide) in the matrix of polyvinyl alcohol for dehydration of ethylene glycol by pervaporation

Polyvinyl alcohol (PVOH) has been chemically modified by crosslink copolymerization of acrylic acid (AA) and acrylamide (AM) in aqueous solution of PVOH and finally crosslinking the copolymer with methylene bis acrylamide (MBA) and PVOH with glutaraldehyde to produce a full interpenetrating network (FIPN) membrane. Accordingly, three such fully crosslinked IPNs i.e. FIPN25, FIPN50 and FIPN75 have been synthesized with different mass ratio of PVOH:copolymer i.e. 1:0.25 (FIPN25), 1:0.50 (FIPN50) and 1:0.75 (FIPN75). These full IPN membranes were used for pervaporative dehydration of ethylene glycol (EG). All of these IPN membranes were characterized with various conventional methods like FTIR, mechanical properties, DTA and SEM. The performances of the membranes were evaluated in terms of sorption and pervaporative dehydration of EG. The IPN membranes were found to show preferential sorption and diffusion for water. Flux and water selectivity of these membranes were found to increase with increasing amount of copolymer in PVOH matrix. However, among the three membranes, FIPN75 were found to show the highest flux but lower selectivity for water while FIPN50 membrane showed optimum performance in terms of both flux and selectivity. Diffusion coefficient and plasticization interaction of water and EG through all the IPN membranes were determined using modified solution-diffusion model.

Interpenetrating network hydrogel membranes of sodium alginate and poly(vinyl alcohol) for controlled release of prazosin hydrochloride through skin

Interpenetrating network (IPN) hydrogel membranes of sodium alginate (SA) and poly(vinyl alcohol) (PVA) were prepared by solvent casting method for transdermal delivery of an anti-hypertensive drug, prazosin hydrochloride. The prepared membranes were thin, flexible and smooth. The X-ray diffraction studies indicated the amorphous dispersion of drug in the membranes. Differential scanning calorimetric analysis confirmed the IPN formation and suggests that the membrane stiffness increases with increased concentration of glutaraldehyde (GA) in the membranes. All the membranes were permeable to water vapors depending upon the extent of cross-linking. The in vitro drug release study was performed through excised rat abdominal skin; drug release depends on the concentrations of GA in membranes. The IPN membranes extended drug release up to 24 h, while SA and PVA membranes discharged the drug quickly. The primary skin irritation and skin histopathology study indicated that the prepared IPN membranes were less irritant and safe for skin application.

Separation of toluene–methanol mixtures by pervaporation using crosslink IPN membranes

Polyvinyl alcohol (PVOH) has been chemically modified by crosslink copolymerization of acrylic acid (AA) and hydroxyethylmethacrylate (HEMA) in aqueous solution of PVOH and finally crosslinking PVOH to produce a full interpenetrating network (IPN) membrane termed as PVAH. Accordingly, three such full crosslink IPNs membranes, i.e. PVAHI, PVAHII and PVAHIII containing varied weight ratio of PVOH and copolymer have been synthesized and used for pervaporative separation of methanol from its mixtures with toluene. For comparison, a conventional PVOH membrane crosslinked with glutaraldehyde has also been used for the same pervaporation study. The flux and selectivity of these IPN membranes were found to be much higher than the conventional glutaraldehyde crosslinked PVOH membrane. Among the three membranes, PVAHII with 50 wt% polyAH incorporation showed optimum performance in terms of flux and methanol selectivity.

Synthesis of Novel Polymeric Membrane for Separation of MTBE-Methanol by Pervaporation

Polyvinyl alcohol(PVOH) has been chemically modified by crosslinking copolymerization of acrylic acid(AA) and hydroxyethylmethacrylate (HEMA) in aqueous solution of PVOH and finally crosslinking PVOH with glutaraldehyde to produce a full interpenetrating network(IPN) membrane. Accordingly, three such full crosslink IPNs i.e., PVAHI, PVAHII and PVAHIII have been synthesized with different weight ratio of PVOH:Poly (AA-co-HEMA) i.e., 1:0.25 (PVAHI), 1:0.50 (PVAHII) and 1:0.75 (PVAHIII). These IPN membranes have been used for pervaporative separation of MTBE-methanol mixtures. All the PVAH membranes were also characterized with various conventional methods like FTIR, mechanical properties, DSC and TGA. Permeability and methanol selectivity of these membranes were found to increase with increasing amount of copolymer in PVOH matrix. However, among the three membranes, PVAHIII were found to show the highest flux but lower selectivity for methanol while PVAHII membrane showed optimum performance in terms of both flux and selectivity.

Separation of isopropyl alcohol–water mixtures by pervaporation using crosslink IPN membranes

Polyvinyl alcohol (PVOH) has been chemically modified by crosslink copolymerization of acrylic acid (AA) and hydroxyethylmethacrylate (HEMA) in aqueous solution of PVOH and finally crosslinking PVOH to produce a full interpenetrating network (IPN) membrane termed as PVAH. Accordingly, three such full crosslink IPNs, i.e. PVAHI, PVAHII and PVAHIII containing varied weight ratio of PVOH and copolymer along with crosslink PVOH (which has not been modified by copolymerization) have been synthesized and used for pervaporative separation of isopropanol (IPA)–water mixtures. Permeability and water selectivity of these membranes were found to increase with increasing amount of copolymer in PVOH matrix. However, among the three membranes, PVAHIII were found to show highest flux but lower selectivity while PVAHI membrane showed optimum performance in terms of both flux and selectivity.

Sulfonated polyimide and poly (ethylene glycol) diacrylate based semi‐interpenetrating polymer network membranes for fuel cells

AbstractSemi‐interpenetrating polymer network (semi‐IPN) membranes based on novel sulfonated polyimide (SPI) and poly (ethylene glycol) diacrylate (PEGDA) have been prepared for the fuel cell applications. SPI was synthesized from 1,4,5,8‐naphthalenetetracarboxylic dianhydride, 4,4′‐diaminobiphenyl 2,2′‐disulfonic acid, and 2‐bis [4‐(4‐aminophenoxy) phenyl] hexafluoropropane. PEGDA was polymerized in the presence of SPI to synthesize semi‐IPN membranes of different ionic contents. These membranes were characterized by determining, ion exchange capacity, water uptake, water stability, proton conductivity, and thermal stability. The proton conductivity of the membranes increased with increasing PEGDA content in the order of 10−1 S cm−1 at 90°C. These interpenetrating network membranes showed higher water stability than the pure acid polyimide membrane. This study shows that semi‐IPN SPI membranes based on PEGDA which gives hydrophilic group and structural stability can be available candidates comparable to Nafion® 117 over 70°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Pervaporation separation of DMF from water using a crosslinked polyurethane urea-PMMA IPN membrane

Interpenetrating network (IPN) membrane of HTPB-based polyurethane urea (PUU) and poly (methyl methacrylate) (PMMA) was developed and used in the pervaporation separation of water-dimethyl formamide (DMF) mixtures of different compositions. From these data the permeation flux, separation selectivity, degree of swelling were calculated at 25, 40 and 60°C. At a higher temperature, the permeation of diffusing molecules through the membrane becomes easier, resulting in an increase of DMF flux. Again with the increase in PMMA content in the membrane the DMF flux and separation selectivity values are increased due to the presence of more polar groups of PMMA. The membrane showed more selectivity towards DMF than water. The highest DMF flux of 0.231 kg/m2.h was obtained for the PUU-PMMA-3 membrane at a temperature of 60°C for 80% DMF in the feed.

Removal of chlorinated volatile organic contaminants from water by pervaporation using a novel polyurethane urea–poly (methyl methacrylate) interpenetrating network membrane

Polymer membranes are potentially selective for separation of organic compounds from a mixture by pervaporation. A novel crosslinked hydroxyterminated polybutadiene based (HTPB) polyurethane urea (PUU)–poly (methyl methacrylate) (PMMA) interpenetrating network (IPN) membrane has been developed for the selective removal of chlorinated volatile organic compounds (VOCs) such as 1 , 1 , 2 , 2 -tetrachloroethane, chloroform, carbon tetrachloride, trichloroethylene present in water in very low concentration by pervaporation. IPNs of different PMMA content and also different crosslink density were used. Since the selective permeation and diffusion of the VOCs through the membrane are dependent on their interaction with the membrane material, their sorption and diffusion behaviors through the membrane were also investigated by swelling the membrane in pure VOCs. The sorption and diffusion behaviors were explained with the help of their solubility parameter data and calculated interaction parameter data of the membrane polymers with the VOCs. From the swelling kinetics data, diffusion coefficients of the VOCs through the membrane were calculated. Diffusion coefficients increased with the increase in crosslink density and PMMA content in the membrane. In pervaporation experiment, concentrations of chlorinated organic compounds in feed were varied from 100 ppm (0.01%) to 1000 ppm (0.1%). All the three IPN membranes showed excellent separation performances of the chlorinated VOCs from water. One IPN containing 26% PMMA (PUU–PMMA-3) produced 88.7% trichloroethylene in permeate, 0.2 kg / m 2 h trichloroethylene flux and a separation factor of 7842 from a 0.1% aqueous feed after a pervaporation run of 3 h at 30 ∘ C . All the three IPN membranes of different compositions have shown the separation performances, viz., flux and separation factor for all the VOCs in the order 1 , 1 , 2 , 2 - tetrachloroethane < carbon tetrachloride < chloroform < trichloroethylene .

Pervaporation separation of aqueous chlorophenols by a novel polyurethane urea–poly (methyl methacrylate) interpenetrating network membrane

A novel polymer membrane system consisting of interpenetrating network (IPN) of hydroxy terminated polybutadiene (HTPB) based polyurethane urea (PUU)–poly (methyl methacrylate) (PMMA) has been designed and developed as highly permselective membrane for pervaporation separation of toxic p-chlorophenol and 2,4-dichlorophenol from their dilute aqueous solutions. It was observed that 3 ppm 2,4-dichlorophenol in water could be reduced to 0.3 ppm 2,4-dichlorophenol using a PUU–PMMA IPN membrane of ∼28 cm 2 area and 150 μm thickness. This membrane has shown high selectivity towards p-chlorophenol and 2,4-dichlorophenol at very low concentration in feed. Feed concentration of p-chlorophenol was varied from 1000 to 7000 ppm and that of 2,4-dichlorophenol was varied from 3 to 4000 ppm. Fifty seven percent 2,4-dichlorophenol in permeate was obtained from 3 ppm concentration in feed compared to 87% 2,4-dichlorophenol in permeate from 1000 ppm in feed. Pervaporation studies were carried out by varying the temperature of feed, membrane thickness and PMMA content in the membrane. The results of this investigation have revealed that these membranes would be suitable for separation of chlorophenols from industrial effluents.

Keratinocyte-fibroblast paracrine interaction: the effects of substrate and culture condition

Interactions between epidermal–dermal cells via soluble factors provide important signals in regulating the reepithelialization of wounded skin. For example, keratinocytes regulate the expression of keratinocyte growth factor (KGF) in fibroblasts through the release of interleukin-1beta (IL-1β). In this study, a previously developed polyethyleneglycol-based interpenetrating network (IPN) system was utilized as a platform for the delivery of keratinocyte-active factors. The effect of substrate chemistry, culture condition, and the delivery of exogenous keratinocyte-active factors on the keratinocyte behavior and the keratinocyte-fibroblast paracrine relationship was delineated. Adherent keratinocyte density on TCPS and glutaraldehyde-fixed gelatin hydrogels but not on IPN was significantly increased with culture time in the presence of growth supplements independent of the released KGF from the gelatin hydrogel and IPN. In the presence of fibroblasts, adherent keratinocyte density on gelatin hydrogels was higher than that without fibroblasts. This phenomenon was not observed on IPN and polycarbonate membrane. In summary, the delivered exogenous huKGF (i.e., released from a biomaterial matrix) operates in tandem with fibroblasts in regulating keratinocyte activation (i.e., IL-lβ release and adhesion) in a surface-dependent manner. Immunoassay analysis of cell culture keratinocyte-fibroblast paracrine relationship as characterized by IL-1β and KGF could not be established in the presence of IPNs, 0.1% glutaraldehyde-fixed gelatin hydrogels, and polycarbonate membranes.

Poly(2‐hydroxyethylmethacrylate)/chitosan dye and different metal‐ion‐immobilized interpenetrating network membranes: Preparation and application in metal affinity chromatography

AbstractComposite membranes were synthesized with 2‐hydroxyethylmethacrylate and chitosan (pHEMA/chitosan) via an ultraviolet‐initiated photopolymerization technique in the presence of an initiator (α,α′‐azobisisobutyronitrile). The interpenetrating network (IPN) membranes were improved by the immobilization of dye molecules via hydroxyl and amino groups on the membrane surfaces from the IPNs. A triazidine dye (Procion Green H‐4G) was covalently immobilized as a ligand onto the IPN membranes. The protein showed various affinities to different chelated metal ions on the membrane surfaces that best matched its own distribution of functional sites, resulting in a distribution of binding energies. In support of this interpretation, two different metal ions, Zn(II) and Fe(III), were chelated with the immobilized dye molecules. The adsorption and binding characteristics of the different metal‐ion‐chelated dye‐immobilized IPN membranes for the lysozyme were investigated with aqueous solutions in magnetically stirred cells. The experimental data were analyzed with two adsorption kinetic models, pseudo‐first‐order and pseudo‐second‐order, to determine the best fit equation for the adsorption of lysozyme onto IPN membranes. The second‐order equation for the lysozyme–dye–metal‐chelated IPN membrane systems was the most appropriate equation for predicting the adsorption capacity for all the tested adsorbents. The reversible lysozyme adsorption on the dye‐immobilized and metal‐ion‐chelated membranes obeyed the Temkin isotherm. The lysozyme adsorption capacity of the pHEMA/chitosan dye, pHEMA/chitosan dye–Zn(II), and pHEMA/chitosan dye–Fe(III) membranes were 2.54, 2.85, and 3.64 mg cm−2, respectively. The nonspecific adsorption of the lysozyme on the plain pHEMA/chitosan membrane was about 0.18 mg cm−2. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1843–1853, 2003

In Vitro Release Study of Verapamil Hydrochloride Through Sodium Alginate Interpenetrating Monolithic Membranes

Polymeric sodium alginate interpenetrating network membranes containing verapamil hydrochloride were fabricated for transdermal application. The membranes were evaluated for their physical properties, weight and thickness uniformity, water vapor transmission, as well as drug content uniformity. All the thin patches were transparent, smooth, and flexible. The drug-loaded membranes were analyzed by X-ray diffraction to understand the drug polymorphism inside the membrane. The transdermal patches were permeable to water vapor, indicating the permeability characteristics of the polymers. The in vitro drug release was performed in distilled water using a Keshary-Chien diffusion cell. The release data were analyzed to understand the mechanism of drug release.

HTPB-H 12MDI based polyurethane IPN membranes for pervaporation

Membranes of hydroxyl terminated polybutadiene (HTPB) and 4,4′-dicyclohexylmethane diisocyanate (H 12MDI) based polyurethane (PU) crosslinked with benzoyl peroxide (BPO) and then formed into an interpenetrating network (IPN) with 4-vinyl pyridine (4-VP) were utilized for the pervaporation separation of water-ethanol mixtures. Membranes of IPN with a content of 8.44 wt% 4-VP have a permeability of 1184 g/m 2 h and a separation factor of 4.11 at 90 wt% aqueous ethanol solution. The effect of hydrophilic-hydrophobic content variation and the crosslinking on the adsorption, transport and morphological properties were investigated. The hydrogen bonding index (HBI) and frequency difference as a measure of the phase segregation and the average strength of the interpolymer hydrogen bonds were utilized to study the sorption phenomenon and permselectivity of the prepared membranes. The change of the glass transition temperature and infrared spectra, which can be used to show the 4-VP content, were detected by DSC and FTIR, respectively. Thermal decomposition behaviors conducted by TGA were used to investigate the formation of IPN.