Enhancement of corrosion protection effect of poly(styrene‐co‐acrylonitrile) by the incorporation of nanolayers of montmorillonite clay into copolymer matrix

A series of polymer–clay nanocomposite (PCN) materials that consisted of poly(styrene‐co‐acrylonitrile) (PSAN) and layered montmorillonite (MMT) clay were successfully prepared by effectively dispersing the inorganic nanolayers of MMT clay into the organic PSAN matrix by a conventional in situ thermal polymerization. First of all, organic styrene and AN monomers at a specific feeding ratio were simultaneously intercalated into the interlayer regions of organophilic clay hosts and followed by a typical free‐radical polymerization with benzyl peroxide as initiator. The as‐synthesized PCN materials were subsequently characterized by FTIR spectroscopy, wide‐angle powder X‐ray diffraction, and transmission electron microscopy. The as‐prepared PCN materials, in the form of coatings, incorporated with low clay loading (e.g., 1 wt %) on cold‐rolled steel, were found to be much superior in corrosion protection over those of bulk PSAN based on a series of standard electrochemical measurements of corrosion potential, polarization resistance, and corrosion current in 5 wt % aqueous NaCl electrolyte. Molecular weights of PSAN extracted from PCN materials and bulk PSAN were determined by gel permeation chromatography with THF as eluant. Effects of the material composition on the molecular barrier and thermal stability of PSAN along with PCN materials, in the form of both membrane and fine powder, were also studied by molecular permeability analysis, differential scanning calorimetry, and thermogravimetric analysis, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2269–2277, 2004     

Preparation and properties of (BATB–ODPA) polyimide–clay nanocomposite materials

A series of polymer–clay nanocomposite (PCN) materials consisting of 1,4‐bis(4‐aminophenoxy)‐2‐tert‐butylbenzene–4,4′‐oxydiphthalic anhydride (BATB–ODPA) polyimide (PI) and layered montmorillonite (MMT) clay were successfully prepared by an in situ polymerization reaction through thermal imidization up to 300°C. The synthesized PCN materials were subsequently characterized by Fourier‐Transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of material composition on thermal stability, mechanical strength, molecular permeability and optical clarity of bulk PI and PCN materials in the form of membranes were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), molecular permeability analysis (GPA) and ultraviolet‐visible (UV/VIS) transmission spectra, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1072–1079, 2004     

Preparation and properties of heterocyclically conjugated poly(3‐hexylthiophene)–clay nanocomposite materials

A series of heterocyclically conjugated polymer–clay nanocomposite (PCN) materials that consisted of organic poly(3‐hexylthiophene) (P3HT) and inorganic montmorillonite (MMT) clay platelets were prepared by in situ oxidative polymerization with FeCl₃ as an oxidant. The as‐synthesized PCN materials were characterized by Fourier transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (WAXRD), and transmission electron microscopy (TEM). The effects of the material composition on the anticorrosion, gas barrier, thermal stability, flammability, mechanical strength, and electrical conductivity properties of the P3HT and PCN materials were studied by electrochemical corrosion measurements, gas‐permeability analysis (GPA), thermogrametric analysis (TGA), limiting oxygen index (LOI) measurements, dynamic mechanical analysis (DMA), and a four‐point probe technique, respectively. The molecular weights of extracted and bulk P3HT were determined by gel permeation chromatography (GPC) with THF as an eluant. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3438–3446, 2004     

Enhanced corrosion prevention effect of polysulfone–clay nanocomposite materials prepared by solution dispersion

A series of polymer–clay nanocomposite (PCN) materials containing polysulfone (PSF) and layered MMT clay were successfully prepared by effectively dispersing inorganic nanolayers of MMT clay in an organic PSF matrix via a solution dispersion technique. The synthesized PCN materials were subsequently investigated with a series of characterization techniques, including Fourier transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The prepared PCN coatings with low clay loading (1 wt %) on cold‐rolled steel (CRS) were found to be superior in corrosion prevention to those of bulk PSF, based on a series of electrochemical measurements of corrosion potential, polarization resistance, corrosion current and electrochemical impedance spectroscopy (EIS) in a 5 wt % aqueous NaCl electrolyte. The effects of material composition on the molecular barrier, mechanical strength and optical clarity of PSF and PCN materials, in the form of membranes, was also studied by molecular permeability analysis (GPA), dynamic mechanical analysis (DMA) and UV‐Visible transmission spectra, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 631–637, 2004     

Effective enhancement of anticorrosive properties of polystyrene by polystyrene–clay nanocomposite materials

A series of polymer–clay nanocomposite (PCN) materials consisting of polystyrene (PS) and layered montmorillonite (MMT) clay was prepared by effectively dispersing the inorganic nanolayers of MMT clay in the organic PS matrix via in situ thermal polymerization. Organic styrene monomers were first intercalated into the interlayer regions of organophilic clay hosts, followed by a typical free radical polymerization with BPO as the initiator. The as‐synthesized PCN materials were characterized by infrared spectroscopy (IR), wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). PCN coatings with low clay loading (1 wt %) on cold‐rolled steel (CRS) were found to be superior in anticorrosion to those of bulk PS, based on a series of electrochemical measurements of corrosion potential, polarization resistance and corrosion current in a 5 wt % aqueous NaCl electrolyte. The molecular weights of PS extracted from PCN materials and bulk PS were determined by gel permeation chromatography (GPC) with tetrahydrofuran (THF) as the eluent. The effects of material composition on molecular barrier and thermal stability of PS and PCN materials, in the form of both free‐standing films and fine powders, were also studied by molecular permeability analysis, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1970–1976, 2004     

Comparative studies of the properties of poly(methyl methacrylate)–clay nanocomposite materials prepared by in situ emulsion polymerization and solution dispersion

A series of polymer–clay nanocomposite (PCN) materials consisting of organic poly(methyl methacrylate) (PMMA) and inorganic montmorillonite (MMT) clay platelets were prepared successfully by the effective dispersion of nanolayers of the MMT clay in the PMMA framework through both in situ emulsion polymerization and solution dispersion. The as‐prepared PCN materials obtained with both approaches were subsequently characterized with wide‐angle powder X‐ray diffraction and transmission electron microscopy. For a comparison of the anticorrosion performance, a PCN material (e.g., 3 wt % clay loading) prepared by in situ emulsion polymerization, showing better dispersion of the clay platelets in the polymer matrix, exhibited better corrosion protection in the form of a coating on a cold‐rolled steel coupon than that prepared by solution dispersion, which showed a poor dispersion of the clay nanolayers according to a series of electrochemical corrosion measurements. Comparative studies of the optical clarity, molecular barrier properties, and thermal stability of samples prepared in both ways, as membranes and fine powders, were also performed with ultraviolet–visible transmission spectroscopy, molecular permeability analysis, thermogravimetric analysis, and differential scanning calorimetry. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1936–1946, 2004     

Structure and properties of poly(o‐methoxyaniline)–clay nanocomposite materials

In this study, we prepared a series of polymer–clay nanocomposite (PCN) materials that consisted of an emeraldine base of poly(o‐methoxyaniline) and layered montmorillonite. Organic o‐methoxyaniline monomers were first intercalated into the interlayer regions of organophilic clay hosts followed by a one‐step in situ oxidative polymerization. The as‐synthesized PCN materials were subsequently characterized by FTIR spectroscopy, wide‐angle powder X‐ray diffraction, and transmission electron microscopy. The molecular weights of PMA extracted from PCN materials and bulk PMA were determined by GPC with THF as eluant. Effects of the material composition on the thermal stability, flame resistance, electrical conductivity, and corrosion inhibition performance of PMA, along with a series of PCN materials in the form of fine powder and coating, were also studied by TGA, limiting oxygen index measurements, four‐point probe technique, and electrochemical corrosion measurements, respectively. Morphological images of as‐synthesized materials were also investigated by SEM. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1072–1080, 2003     

Organo‐soluble polyimde (ODA–BSAA)/montmorillonite nanocomposite materials prepared by solution dispersion technique

A series of polymer–clay nanocomposite materials, consisting of organo‐soluble polyimide (ODA‐BSAA) matrix and dispersed nanolayers of inorganic montmorillonite clay, were successfully prepared by solution dispersion technique and subsequently characterized by FTIR, powder X‐ray diffraction patterns, transmission electron microscopy, and atomic force microscopy. Effects of the materials composition on the corrosion protection performance, gas barrier, and optical properties, in the form of both coating and film, were also studied by electrochemical corrosion measurements (e.g., corrosion potential, polarization resistance, corrosion current, impedance spectroscopy), gas permeability analysis, and UV–visible transmission spectroscopy, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1082–1090, 2005     

Poly(N‐vinylcarbazole)–clay nanocomposite materials prepared by photoinitiated polymerization with triarylsulfonium salt initiator

A series of polymer–clay nanocomposite (PCN) materials that consist of poly(N‐vinylcarbazole) (PNVC) and layered montmorillonite (MMT) clay are prepared by effectively dispersing the inorganic nanolayers of MMT in an organic PNVC matrix via in situ photoinitiated polymerization with triarylsulfonium salt as the initiator. Organic NVC monomers are first intercalated into the interlayer regions of the organophilic clay hosts, followed by one‐step UV‐radiation polymerization. The as‐synthesized PCN materials are typically characterized by Fourier transform IR spectroscopy, wide‐angle X‐ray diffraction, and transmission electron microscopy. The molecular weights of PNVCs extracted from the PCN materials and the bulk PNVC are determined by gel permeation chromatography analysis with tetrahydrofuran as the eluant. The morphological image of the synthesized materials is observed by an optical polarizing microscope. The effects of the material composition on the optical properties and thermal stability of PNVCs and a series of PCN materials (solution and fine powder) are also studied by UV–visible absorption spectra measurements, thermogravimetric analysis, and differential scanning calorimetry, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1904–1912, 2004     

Polyacrylamide–clay nanocomposite materials prepared by photopolymerization with acrylamide as an intercalating agent

A series of nanocomposite materials consisting of water‐soluble polyacrylamide (PAA) and layered montmorillonite (MMT) clay platelets were prepared by the effective dispersion of the inorganic nanolayers of the MMT clay in the organic PAA matrix via in situ ultraviolet‐radiation polymerization. The acrylamide monomers functioned as both the intercalating agent and the reacting monomers. As a representative procedure for the preparation of the nanocomposites, organic acrylamide monomers were first intercalated into the interlayer regions of acrylamide‐treated organophilic clay hosts, and this was followed by one‐step ultraviolet‐radiation free‐radical polymerization with benzil as a photoinitiator. The as‐prepared polyacrylamide–clay nanocomposite (PCN) materials were subsequently characterized by Fourier transform infrared spectroscopy, wide‐angle powder X‐ray diffraction, and transmission electron microscopy. The effects of the material composition on the thermal stability, optical clarity, and gas‐barrier properties of pristine PAA and PCN materials, in the forms of fine powders and membranes, were also studied by differential scanning calorimetry, thermogravimetric analysis, ultraviolet–visible transmission spectroscopy, and gas permeability analysis. The molecular weights of PAA extracted from PCN materials and pristine PAA were determined by gel permeation chromatography with tetrahydrofuran as an eluant. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3489–3496, 2004     

Enhanced corrosion protection coatings prepared from soluble electronically conductive polypyrrole‐clay nanocomposite materials

A series of electronically conductive nanocomposite materials that consisted of soluble polypyrrole (PPY) and layered montmorillonite (MMT) clay platelets were prepared by effectively dispersing the inorganic nanolayers of MMT clay in organic PPY matrix via an in situ oxidative polymerization with dodecylbenzene sulfonic acid (DBSA) as dopant. Organic pyrrole monomers were first intercalated into the interlayer regions of organophilic clay hosts and followed by a one‐step oxidative polymerization. The as‐synthesized electronically conductive polypyrrole–clay nanocomposite (PCN) materials were then characterized by Fourier transformation infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (XRD), and transmission electron microscopy (TEM). PCNs in the form of coatings with low clay loading (e.g., 1.0 wt %) on cold‐rolled steel (CRS) were found to exhibit much better in corrosion protection over those of pristine PPY based on a series of electrochemical measurements including corrosion potential, polarization resistance, and corrosion current in 5 wt % aqueous NaCl electrolyte. Effects of the material composition on the thermal stability, optical properties, and electrical conductivity of pristine PPY along with PCN materials, in the form of fine powder, powder‐pressed pellet, and solution, were also studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), UV‐visible absorption spectra, and four‐point probe technique, respectively. The viscosity of PPY existed in PCN materials and pristine PPY were determined by viscometric analysis with m‐cresol as solvent. The heterogeneous nucleating effect of MMT clay platelets in PPY matrix was studied by wide‐angle powder XRD. The corresponding morphological images of the nucleating behavior of clay platelets in PPY matrix were investigated by scanning electron microscopy (SEM). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3264–3272, 2003     

Comparative studies on corrosion protection properties of polyimide‐silica and polyimide‐clay composite materials

Comparative studies on corrosion protection properties of polyimide‐silica‐clay composites were studied in this article. A series of polyimide‐silica (PIS), polyimide‐clay (PIC), and polyimide‐silica‐clay composites (PISC) materials, consisting of an organo‐soluble polyimide (ODA‐BSAA) matrix, inorganic silica particles prepared through the sol–gel reaction of tetraethyl orthosilicate (TEOS) and dispersed nanolayers of inorganic montmorillonite clay, were successfully prepared by solution dispersion technique. Then, all samples were characterized by FTIR, powder X‐ray diffraction patterns, transmission electron microscopy, and ²⁹Si solid‐state NMR. The main focus of this article is the comparison of the corrosion protection properties of PIS, PIC, and PISC composite materials. Normally, the aspect ratio of clay is higher than silica. Superior dispersion of clay platelets into a polymer matrix may effectively increase the length of diffusion pathways for oxygen and water. The effects of the materials composition on the corrosion protection performance, gas barrier, and optical properties, in the form of both coating and film, were also studied by electrochemical corrosion measurements (e.g., corrosion potential, polarization resistance, corrosion current, and impedance spectroscopy), gas permeability analysis, and UV‐visible transmission spectroscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Enhancement of corrosion protection effect of poly(o-ethoxyaniline) via the formation of poly(o-ethoxyaniline)-clay nanocomposite materials

A series of polymer-clay nanocomposite (PCN) materials that consisted of emeraldine base of poly(o-ethoxyaniline) (PEA) and layered montmorillonite (MMT) clay were prepared by effectively dispersing the inorganic MMT clay platelets in organic PEA matrix via in situ oxidative polymerization. Organic o-ethoxyaniline monomers were first intercalated into the interlayer regions of organophilic clay hosts and were followed by a one-step oxidative polymerization. The as-synthesized PCN materials were characterized by Fourier transform infrared (FTIR) spectroscopy, wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM).PCN materials at low clay loading up to 3 wt% in the form of coating (e.g. 0.5 wt%) on cold-rolled steel (CRS) were found to exhibit much superior corrosion inhibition effect as compared to those of the bulk PEA by performing a series of electrochemical measurements of corrosion potential, polarization resistance, corrosion current and impedance spectroscopy in 5 wt% aqueous NaCl electrolyte. Furthermore, it was found that a further increase of clay loading up to 3 wt% results in a slightly enhanced molecular barrier property of PCN materials. The molecular weights of PEA extracted from PCN materials and bulk PEA were determined by gel permeation chromatography (GPC) analysis with NMP as eluant. Effects of the material composition on the molecular barrier, thermal stability, electrical conductivity and optical properties of PEA along with a series of PCN materials, in the form of free-standing film, fine powder and solution, were also studied by molecular permeability measurements (GPA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), four-point probe technique and UV-vis spectra.     

Synthesis and dielectric properties of poly(methyl methacrylate)–clay nanocomposite materials

Poly(methyl methacrylate) (PMMA)–clay nanocomposite (PCN) materials were synthesized through in situ intercalative polymerization. A cationic surfactant, [2(dimethylamino)ethyl]triphenylphosphonium bromide, was used as an intercalating agent with pristine Na⁺‐montmorillonite (MMT). The synthesized PCN materials were subsequently investigated by a series of characterization techniques, including wide‐angle powder X‐ray diffraction, Fourier transform IR spectroscopy, transmission electron microscopy, thermogravimetric analysis, and differential scanning calorimetry. Compared to pure PMMA, the PCN materials exhibit higher thermal degradation temperatures and glass‐transition temperatures. The dielectric properties of PCN blending with a commercial PMMA material in film form with clay loading from 0.5 to 5.0 wt % were measured under frequencies of 100 Hz–1 MHz at 35–100°C. Significantly depressed dielectric constants and losses were observed for these PCN‐blending materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2175–2181, 2005     

High‐performance polyimide–clay nanocomposite materials based on a dual intercalating agent system

BACKGROUND: Polymer–clay nanocomposites (PCNs) have attracted considerable interest in recent years owing to their unique physical and chemical properties that lead to a wide range of applications. A series of PCN materials consisting of polyimide and layered montmorillonite (MMT) clay were successfully prepared by in situ polymerization. RESULTS: Silicate layers are better dispersed in polymer matrices when dual intercalating agents (hexadecyltrimethylammonium bromide–4,4′‐oxydianiline) are applied for MMT modification according to wide‐angle X‐ray diffraction and transmission electron microscopy studies. Effects of single and dual intercalating agents on thermal stability, mechanical strength and the molecular barrier of PCN materials consisting of organo‐modified MMT were studied by means of thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analyses, gas permeability analysis and vapor permeability analysis. CONCLUSION: Improved thermal and mechanical stabilities, as well as barrier properties were observed for the PCN materials containing dual intercalating agent‐modified MMT. Copyright © 2008 Society of Chemical Industry     

Designing of fullers‐earth‐containing poly(vinyl alcohol)‐g‐poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) nanocomposites: Swelling and deswelling behaviors

In this study, polymer–clay nanocomposites (PCNs) composed of poly(vinyl alcohol)s (PVAs), poly(2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid), and fullers earth were prepared by the effective dispersal of inorganic nanoclays in the organic PVA matrix via in situ free‐radical polymerization with potassium persulfate as an initiator and N,N‐methylene bisacrylamide as a crosslinker. The monomer, 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid, was grafted onto the PVA backbone, and at the same time, fullers earth layers were intercalated and exfoliated into the grafted copolymer, especially at a low or moderate loading of the fullers earth. The synthesized PCN materials were characterized by Fourier transform infrared spectroscopy and wide‐angle X‐ray diffraction techniques. The morphological features of the synthesized materials were studied by scanning electron microscopy; this revealed that the swelling ratio of this nanocomposite increased with increasing fullers earth content. The X‐ray diffraction results indicated that the fullers earth was exfoliated in the nanocomposite matrix, and its introduction into the polymer matrix enhanced the percentage crystallinity of the polymer. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Comparative studies on the corrosion protection effect of DBSA-doped polyaniline prepared from in situ emulsion polymerization in the presence of hydrophilic Na-MMT and organophilic organo-MMT clay platelets

A series of polyaniline (PANI)/Na⁺-montmorillonite (MMT) clay and PANI/organo-MMT nanocomposite materials have been successfully prepared by in situ emulsion polymerization in the presence of inorganic nanolayers of hydrophilic Na⁺-MMT clay or organophilic organo-MMT clay with DBSA and KPS as surfactant and initiator, respectively. The as-synthesized Na⁺-PCN and organo-PCN materials were characterized and compared by Fourier transformation infrared (FTIR) spectroscopy, wide-angle powder X-ray diffraction (XRD) and transmission electron microscopy (TEM).Na⁺-PCN materials in the form of coatings with low loading of Na⁺-MMT clay (e.g., 3 wt.%, CLAN3) on cold-rolled steel (CRS) were found much superior in corrosion protection over those of organo-PCN materials with same clay loading based on a series of electrochemical measurements of corrosion potential, polarization resistance, corrosion current and impedance spectroscopy in 5 wt.% aqueous NaCl electrolyte. The molecular weights of PANI extracted from PCN materials and neat PANI were determined by gel permeation chromatography (GPC) with NMP as eluant. Effects of material composition on the gas permeability, optical properties and electrical conductivity of neat PANI and a series of PCN materials, in the form of free-standing film, solution and powder-pressed pellet, were also studied by gas permeability analyzer (GPA), ultraviolet-vis spectra and four-point probe technique, respectively.     

Studies on heterogeneous nucleation effect of dispersing intercalated montmorillonite clay platelets in polyaniline matrix

In this article, a series of nanocomposite materials that consisted of emeraldine base (EB) of polyaniline (PANI) and montmorillonite (MMT) clay were prepared by effectively dispersing the inorganic MMT clay platelets into organic PANI matrix via in situ chemically oxidative polymerization. Organic aniline monomers were first intercalated into the interlayer regions of organophilic clay hosts and followed by an one‐step oxidative polymerization with ammonium persulfate as oxidant. The as‐synthesized PANI‐clay nanocomposite (PCN) materials were characterized by Fourier‐Transformation infrared spectroscopy and transmission electron microscopy. It should be noted that the EB of PANI in the presence of dispersed intercalated MMT clay platelets was found to display an observable enhancement in polymer crystallinity as compared with that of neat PANI based on series of investigations of wide‐angle powder X‐ray diffraction patterns and differential scanning calorimetric studies. This remarkable increase of polymer crystallinity might be resulted from the effective heterogeneous nucleation effect of dispersed clay platelets existed in PCN materials. The surface morphology study of PCN materials was further evaluated by polarizing optical microscopy, scanning electron microscopy, and atomic force microscopy. POLYM. COMPOS., 31:2049–2056, 2010. © 2010 Society of Plastics Engineers     

Advanced anticorrosive materials prepared from amine-capped aniline trimer-based electroactive polyimide-clay nanocomposite materials with synergistic effects of redox catalytic capability and gas barrier properties

In this study, preparation and electrochemical corrosion protection studies of a series of polyimide-Clay nanocomposite (PCN) materials were first presented. Subsequently, the as-prepared PCN materials were characterized by FTIR, XRD and TEM studies. In-situ monitoring for redox behavior of as-prepared PCN materials was identified by UV-visible and CV studies.It should be noted that PCN coating was found to reveal advanced corrosion protection effect on cold-rolled steel (CRS) electrode as compared to that of neat non-electroactive polyimide coating based on series of electrochemical corrosion measurements in 5 wt% NaCl electrolyte. Enhancement of corrosion protection of PCN coatings on CRS electrode may be interpreted by following two possible reasons: (1) redox catalytic capabilities (i.e., electroactivity) of ACAT units existed in electroactive PCN may induce formation of passive metal oxide layers on CRS electrode, as evidenced by SEM and ESCA studies. (2) well-dispersed layered organophilic clay platelets embedded in electroactive PCN matrix could functioned as hinder with high aspect ratio to effectively enhance the oxygen barrier property of PCN, as evidenced by GPA.     

Effect of organoclays on the thermal,mechanical, and oxygen barrier properties of poly(methylmethacrylate‐co‐acrylonitrile)/clay nanocomposites

The nanostructured hybrid materials of poly(methylmethacrylate‐co‐acrylonitrile) copolymer were synthesized with incorporation of two organically modified clays, Cloisite® 30B and 93A by in situ intercalative emulsifier‐free emulsion polymerization method. The synthesized products were characterized by Fourier transform infrared spectroscopy to get evidence of copolymerization and formation of copolymer‐clay nanocomposite. X‐ray diffraction study and transmission electron microscopy analysis revealed that the clays were successfully intercalated and exfoliated into the copolymer matrix. Thermal properties of the nanocomposites were studied as a function of clay content of different clay types by thermogravimetric analysis. The results showed significant effect of both the clays in enhancing thermal resistance of the materials. Mechanical properties of the composites were also found to be improved at optimum clay loading. Oxygen barrier property of these materials was measured and it was found that the oxygen permeability was reduced almost by half due to incorporation of clays at 3% loading. Further, it was observed that Cloisite® 93A was more effective for improvement in properties when compared with Cloisite® 30B in the hybrid materials. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers