The Experts below are selected from a list of 135 Experts worldwide ranked by ideXlab platform

Abdolreza Aroujalian - One of the best experts on this subject based on the ideXlab platform.

  • surface modification of polyethersulfone ultrafiltration membranes by Corona plasma assisted coating tio2 nanoparticles
    Journal of Membrane Science, 2014
    Co-Authors: Vahid Moghimifar, Ahmadreza Raisi, Abdolreza Aroujalian
    Abstract:

    In this work, the surface of polyethersulfone (PES) ultrafiltration membranes was modified by Corona air plasma and coating TiO2 nanoparticles in order to improve the separation and antifouling properties. For this purpose, the TiO2 nanoparticles which were synthesized in a rutile phase by a microwave hydrothermal method, were coated on the surface of the Corona plasma treated PES membranes which were prepared via the non-solvent-induced phase inversion method. The effects of Corona Treatment conditions on the morphology, surface properties and separation performance of the modified membranes were studied. The fabricated membranes were characterized by FTIR-ATR, SEM, AFM and contact angle analysis. The fouling resistance and separation performance of the membranes were also evaluated by the UF permeation tests of pure water and oil in water emulsions. The experimental results showed that the Corona Treatment and coating TiO2 nanoparticles led to a significant enhancement of the surface hydrophilicity, improvement of the antifouling properties and permeation fluxes for all modified membranes without significant changes in cross sectional morphology of the membranes. The modified membranes had a lower fouling tendency and long term flux stability in comparison to the untreated PES membranes. Furthermore, an increase in the Corona input power and Treatment time resulted in higher hydrophilicity of the membrane surface as well as much more deposition of TiO2 nanoparticles on the membrane.

  • surface modification of polyethersulfone ultrafiltration membranes by Corona air plasma for separation of oil water emulsions
    Journal of Membrane Science, 2013
    Co-Authors: Ilin Sadeghi, Ahmadreza Raisi, Abdolreza Aroujalian, Bahram Dabir, Mahdi Fathizadeh
    Abstract:

    Abstract This study focuses on the surface modification of polyethersulfone (PES) ultrafiltration (UF) membranes using Corona air plasma in order to reduce membrane fouling during separation of oil/water emulsions. The PES membranes were fabricated using polyvinylpyrrolidone (PVP) as a pore forming agent with various solvents including N , N -dimethylacetamide (DMAc), N , N -dimethyl-formamide (DMF), 1-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) by the phase inversion method. The effects of solvent in casting solution and Corona Treatment conditions on the surface properties, membrane morphology and separation performance of the membranes were investigated. The ATR-FTIR, SEM and AFM analyses were used to characterize the untreated and Corona treated membranes. The results showed that viscosity of the casting solution and difference in solubility parameter between the solvent and non-solvent play an important role in the membrane structure and performance, however, the effect of viscosity is more pronounced. The Corona Treatment led to significant enhancement of the surface hydrophilicity, improvement of anti-fouling properties and oil/water flux in all membranes without significant changes in oil rejection. The effect of Corona parameters on DMSO-solvent membrane indicated that the Corona needs more time or higher power to ablate the surface, widening the pore distribution and enhancing permeation in case of membranes with a thicker dense layer.

Ahmadreza Raisi - One of the best experts on this subject based on the ideXlab platform.

  • surface modification of polyethersulfone ultrafiltration membranes by Corona plasma assisted coating tio2 nanoparticles
    Journal of Membrane Science, 2014
    Co-Authors: Vahid Moghimifar, Ahmadreza Raisi, Abdolreza Aroujalian
    Abstract:

    In this work, the surface of polyethersulfone (PES) ultrafiltration membranes was modified by Corona air plasma and coating TiO2 nanoparticles in order to improve the separation and antifouling properties. For this purpose, the TiO2 nanoparticles which were synthesized in a rutile phase by a microwave hydrothermal method, were coated on the surface of the Corona plasma treated PES membranes which were prepared via the non-solvent-induced phase inversion method. The effects of Corona Treatment conditions on the morphology, surface properties and separation performance of the modified membranes were studied. The fabricated membranes were characterized by FTIR-ATR, SEM, AFM and contact angle analysis. The fouling resistance and separation performance of the membranes were also evaluated by the UF permeation tests of pure water and oil in water emulsions. The experimental results showed that the Corona Treatment and coating TiO2 nanoparticles led to a significant enhancement of the surface hydrophilicity, improvement of the antifouling properties and permeation fluxes for all modified membranes without significant changes in cross sectional morphology of the membranes. The modified membranes had a lower fouling tendency and long term flux stability in comparison to the untreated PES membranes. Furthermore, an increase in the Corona input power and Treatment time resulted in higher hydrophilicity of the membrane surface as well as much more deposition of TiO2 nanoparticles on the membrane.

  • surface modification of polyethersulfone ultrafiltration membranes by Corona air plasma for separation of oil water emulsions
    Journal of Membrane Science, 2013
    Co-Authors: Ilin Sadeghi, Ahmadreza Raisi, Abdolreza Aroujalian, Bahram Dabir, Mahdi Fathizadeh
    Abstract:

    Abstract This study focuses on the surface modification of polyethersulfone (PES) ultrafiltration (UF) membranes using Corona air plasma in order to reduce membrane fouling during separation of oil/water emulsions. The PES membranes were fabricated using polyvinylpyrrolidone (PVP) as a pore forming agent with various solvents including N , N -dimethylacetamide (DMAc), N , N -dimethyl-formamide (DMF), 1-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) by the phase inversion method. The effects of solvent in casting solution and Corona Treatment conditions on the surface properties, membrane morphology and separation performance of the membranes were investigated. The ATR-FTIR, SEM and AFM analyses were used to characterize the untreated and Corona treated membranes. The results showed that viscosity of the casting solution and difference in solubility parameter between the solvent and non-solvent play an important role in the membrane structure and performance, however, the effect of viscosity is more pronounced. The Corona Treatment led to significant enhancement of the surface hydrophilicity, improvement of anti-fouling properties and oil/water flux in all membranes without significant changes in oil rejection. The effect of Corona parameters on DMSO-solvent membrane indicated that the Corona needs more time or higher power to ablate the surface, widening the pore distribution and enhancing permeation in case of membranes with a thicker dense layer.

Taweechai Amornsakchai - One of the best experts on this subject based on the ideXlab platform.

  • surface modification of biaxially oriented polypropylene bopp film using acrylic acid Corona Treatment part ii long term aging surface properties
    Surface & Coatings Technology, 2013
    Co-Authors: Nanticha Kalapa, Taweechai Amornsakchai, Toemsak Srikhiri
    Abstract:

    Abstract In this work particular attention has been paid to the aging behavior of biaxially oriented polypropylene (BOPP) film surfaces modified with the acrylic acid (AAc) Corona discharge Treatment previously reported. Three different Corona energies of 15.3, 38.2 and 76.4 kJ/m 2 were studied. The surface properties of treated films during 90 days of aging were compared with those of normal air-Corona treated films prepared with the same Corona energies. The surface chemical compositions of aged films were analyzed by curve-fitting of the ATR-FTIR spectra. The wettabilities of all aged films were monitored by water contact angle and surface free energy measurements. The change of surface topology of air- and AAc-Corona treated films was investigated at 1 day, 7 days and 90 days of aging using the AFM technique. In addition, the surface adhesions of aged films were determined with the T-peeling test. The results showed that the amount of polar functional groups on the surface of aged films had changed. However, the aged films of the AAc-Corona treated films still showed greater wettability than did the air-Corona treated films and could retain high surface hydrophilicity for more than 90 days of aging under ambient condition. The surface topology of both types of aged films changed after aging from a globular structure to a flatter surface, due to mobility of the deposited polymer layer. The AAc-Corona treated films showed rougher surfaces due to the influence of poly(acrylic acid) deposition and they could retain the improved surface wettability despite the change in surface topography. The adhesion peel forces of aged films decreased slightly due to the topological changes. A mechanism for the change in surface topography and in chemical functionality of each type of aged film is proposed.

  • surface modification of biaxially oriented polypropylene bopp film using acrylic acid Corona Treatment part i properties and characterization of treated films
    Surface & Coatings Technology, 2012
    Co-Authors: Nanticha Kalapa, Taweechai Amornsakchai
    Abstract:

    Abstract In this work, the acrylic acid (AAc)-Corona discharge was carried out on biaxially oriented polypropylene (BOPP) films by introducing AAc vapor into the Corona region of a normal Corona treater. Three different Corona energies of 15.3, 38.2 and 76.4 kJ/m 2 were studied. Surface properties of treated films were compared with those of air-Corona treated films prepared with the same Corona energies. The change in chemical composition on the film surface was characterized by curve-fitting of the ATR-FTIR spectra. The wettability of treated films, before and after aging in different environments, was observed by water contact angle and surface free energy. The surface morphology of air- and AAc-Corona treated films was investigated using SEM and AFM techniques. Adhesion of the treated films to some other substrate was determined with the T-peeling test. It was found that the hydrophilicity of all treated films increased with increasing Corona energy. AAc-Corona treated films showed greater wettability than did the air-Corona treated films and could retain the surface hydrophilicity for more than 90 days of aging under ambient conditions. The surface morphology of BOPP films changed after Corona Treatment into a globular structure. The AAc-Corona treated films showed rougher surfaces due to surface oxidation and polymer formation, whereas, air-Corona treated films displayed a similar structure but of smaller size due to the formation of low molecular weight oxidized materials (LMWOM) arising from the degradation of BOPP films. AAc-Corona treated films showed greater peel strength than did the air-Corona treated films.

Mahdi Fathizadeh - One of the best experts on this subject based on the ideXlab platform.

  • surface modification of polyethersulfone ultrafiltration membranes by Corona air plasma for separation of oil water emulsions
    Journal of Membrane Science, 2013
    Co-Authors: Ilin Sadeghi, Ahmadreza Raisi, Abdolreza Aroujalian, Bahram Dabir, Mahdi Fathizadeh
    Abstract:

    Abstract This study focuses on the surface modification of polyethersulfone (PES) ultrafiltration (UF) membranes using Corona air plasma in order to reduce membrane fouling during separation of oil/water emulsions. The PES membranes were fabricated using polyvinylpyrrolidone (PVP) as a pore forming agent with various solvents including N , N -dimethylacetamide (DMAc), N , N -dimethyl-formamide (DMF), 1-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) by the phase inversion method. The effects of solvent in casting solution and Corona Treatment conditions on the surface properties, membrane morphology and separation performance of the membranes were investigated. The ATR-FTIR, SEM and AFM analyses were used to characterize the untreated and Corona treated membranes. The results showed that viscosity of the casting solution and difference in solubility parameter between the solvent and non-solvent play an important role in the membrane structure and performance, however, the effect of viscosity is more pronounced. The Corona Treatment led to significant enhancement of the surface hydrophilicity, improvement of anti-fouling properties and oil/water flux in all membranes without significant changes in oil rejection. The effect of Corona parameters on DMSO-solvent membrane indicated that the Corona needs more time or higher power to ablate the surface, widening the pore distribution and enhancing permeation in case of membranes with a thicker dense layer.

Nanticha Kalapa - One of the best experts on this subject based on the ideXlab platform.

  • surface modification of biaxially oriented polypropylene bopp film using acrylic acid Corona Treatment part ii long term aging surface properties
    Surface & Coatings Technology, 2013
    Co-Authors: Nanticha Kalapa, Taweechai Amornsakchai, Toemsak Srikhiri
    Abstract:

    Abstract In this work particular attention has been paid to the aging behavior of biaxially oriented polypropylene (BOPP) film surfaces modified with the acrylic acid (AAc) Corona discharge Treatment previously reported. Three different Corona energies of 15.3, 38.2 and 76.4 kJ/m 2 were studied. The surface properties of treated films during 90 days of aging were compared with those of normal air-Corona treated films prepared with the same Corona energies. The surface chemical compositions of aged films were analyzed by curve-fitting of the ATR-FTIR spectra. The wettabilities of all aged films were monitored by water contact angle and surface free energy measurements. The change of surface topology of air- and AAc-Corona treated films was investigated at 1 day, 7 days and 90 days of aging using the AFM technique. In addition, the surface adhesions of aged films were determined with the T-peeling test. The results showed that the amount of polar functional groups on the surface of aged films had changed. However, the aged films of the AAc-Corona treated films still showed greater wettability than did the air-Corona treated films and could retain high surface hydrophilicity for more than 90 days of aging under ambient condition. The surface topology of both types of aged films changed after aging from a globular structure to a flatter surface, due to mobility of the deposited polymer layer. The AAc-Corona treated films showed rougher surfaces due to the influence of poly(acrylic acid) deposition and they could retain the improved surface wettability despite the change in surface topography. The adhesion peel forces of aged films decreased slightly due to the topological changes. A mechanism for the change in surface topography and in chemical functionality of each type of aged film is proposed.

  • surface modification of biaxially oriented polypropylene bopp film using acrylic acid Corona Treatment part i properties and characterization of treated films
    Surface & Coatings Technology, 2012
    Co-Authors: Nanticha Kalapa, Taweechai Amornsakchai
    Abstract:

    Abstract In this work, the acrylic acid (AAc)-Corona discharge was carried out on biaxially oriented polypropylene (BOPP) films by introducing AAc vapor into the Corona region of a normal Corona treater. Three different Corona energies of 15.3, 38.2 and 76.4 kJ/m 2 were studied. Surface properties of treated films were compared with those of air-Corona treated films prepared with the same Corona energies. The change in chemical composition on the film surface was characterized by curve-fitting of the ATR-FTIR spectra. The wettability of treated films, before and after aging in different environments, was observed by water contact angle and surface free energy. The surface morphology of air- and AAc-Corona treated films was investigated using SEM and AFM techniques. Adhesion of the treated films to some other substrate was determined with the T-peeling test. It was found that the hydrophilicity of all treated films increased with increasing Corona energy. AAc-Corona treated films showed greater wettability than did the air-Corona treated films and could retain the surface hydrophilicity for more than 90 days of aging under ambient conditions. The surface morphology of BOPP films changed after Corona Treatment into a globular structure. The AAc-Corona treated films showed rougher surfaces due to surface oxidation and polymer formation, whereas, air-Corona treated films displayed a similar structure but of smaller size due to the formation of low molecular weight oxidized materials (LMWOM) arising from the degradation of BOPP films. AAc-Corona treated films showed greater peel strength than did the air-Corona treated films.