Ultrasonic oscillations induced morphology and property development of polypropylene/montmorillonite nanocomposites

Polypropylene/montmorillonite nanocomposites (PPCNs) with 3% organophilic montmorillonite (OMMT) content were prepared via ultrasonic extrusion. The objective of present study was to investigate the effects of ultrasonic oscillations in processing on the morphology and property development of PPCNs. XRD and TEM results confirmed the intercalated structure of OMMT in conventional nanocomposite (without ultrasonic treatment) and ultrasonicated nanocomposite, but ultrasonic oscillations could make silicate layers finely dispersed and a little exfoliated. According to SEM, the OMMT particles were evenly and finely dispersed in the ultrasonicated nanocomposite via ultrasonic oscillations, and the aggregation size of clay particles was about 100 nm, which is less than that in conventional nanocomposite. The crystalline dimension, crystalline morphology and the growth rate of crystallization in PPCNs were investigated by DSC and PLM, it was found that the OMMT particles and ultrasonic oscillations played an important role in the nucleation rate, crystallization temperature and spherulite size of PP matrix in nanocomposites. Compared with conventional nanocomposite, the mechanical properties of the ultrasonicated nanocomposite increased due to the improved dispersion of OMMT and diminished spherulite size. The thermal stability and the rheological behavior of PP and its nanocomposites were both studied by thermogravimetry and high pressure rheometer, respectively.     

Dispersion characteristics and rheology of organoclay nanocomposites based on a segmented main-chain liquid-crystalline polymer having side-chain azopyridine with flexible spacer

The dispersion characteristics and rheology of organoclay nanocomposites based on a main-chain liquid-crystalline polymer having side-chain azopyridine with flexible spacer (PABP) were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), and oscillatory shear rheometry. In the preparation of nanocomposites via solution blending under vigorous stirring, two commercial organoclays (Southern Clay Products) were employed: one (Cloisite 30B) treated with a surfactant (MT2EtOH) having hydroxyl groups, and the other (Cloisite 20A) treated with a nonpolar surfactant (2M2HT) having hydrogenated tallow. Also prepared, for comparison, were nanocomposites prepared by mixing PABP with natural clay (montmorillonite, MMT). The following observations were made. (i) PABP/Cloisite 30B nanocomposite has featureless XRD patterns and a very high degree of dispersion of Cloisite 30B aggregates as determined from TEM. (ii) PABP/Cloisite 20A nanocomposite has shown a conspicuous XRD reflection peak and intercalation of Cloisite 20A aggregates as determined from TEM. (iii) PABP/MMT nanocomposite has shown XRD patterns, which are virtually the same as the XRD patterns of neat PABP with a slightly increased gallery distance, and it has very poor dispersion of MMT aggregates in the matrix of PABP. The observed high degree of dispersion of Cloisite 30B aggregates in PABP/Cloisite 30B nanocomposite is attributable to the formation of hydrogen bonds between the pyridyl group of side-chain azopyridine and the hydroxyl groups in the surfactant MT2EtOH residing at the surface of Cloisite 30B. The presence of hydrogen bonds in the PABP/Cloisite 30B nanocomposite was confirmed by in situ Fourier transform infrared (FTIR) spectroscopy. It was observed via polarized optical microscopy that the liquid crystallinity of PABP in the PABP/Cloisite 30B nanocomposites was more or less intact with a very high degree of dispersion of Cloisite 30B aggregates. Oscillatory shear flow measurements of the organoclay nanocomposites prepared support the conclusions drawn from XRD, TEM, and FTIR spectroscopy.     

New aramid‐based nanocomposites: Synthesis and characterization

New type of nanocomposites containing various proportions of montmorillonite in aromatic polyamide was prepared via solution intercalation method. Aramid chains were synthesized by reacting 4,4′‐oxydianiline with isophthaloyl chloride in N,N′‐dimethyl acetamide. Dodecylamine was used as swelling agent to change the hydrophilic nature of montmorillonite into organophilic. Appropriate amounts of organoclay were mixed in the polymer solution using high‐speed mixer for complete dispersion of the clay. Thin films cast from these materials after evaporating the solvent were characterized by XRD, TEM, mechanical, thermal, and water absorption measurements. The structure and morphology of the nanocomposites determined by XRD and TEM revealed the formation of exfoliated and intercalated clay platelets in the aramid matrix. Mechanical data indicated improvement in the tensile strength and modulus of the nanocomposites with clay loading up to 6 wt%. The glass transition temperature increased up to 12 wt% clay content and thermal stability amplified with increasing clay loading. The water absorption reduced gradually as a function of organoclay and approached to zero with 20 wt% organoclay in the aramid. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Use of purified and modified bentonites in linear low‐density polyethylene/organoclay/compatibilizer nanocomposites

Polyethylene‐based ternary nanocomposites were prepared with different clay structures, obtained by the modification of purified Resadiye bentonite as the reinforcement, a random terpolymer of ethylene, butyl acrylate, and maleic anhydride with the trade name Lotader3210 as the compatibilizer, and linear low‐density polyethylene (LLDPE) as the polymer matrix in an intensive batch mixer. The quaternary ammonium/phosphonium salts used for the modification of bentonite were dimethyldioctadecyl ammonium (DMDA) chloride (Cl), tetrakisdecyl ammonium (TKA) bromide (Br), and tributylhexadecyl phosphonium (TBHP) Br. The effects of the physical properties and structure of the organoclay on the clay dispersion were studied at different clay contents (2 and 5 wt %) and at a compatibilizer/organoclay ratio of 2.5. The extent of organoclay dispersion was determined by X‐ray diffraction (XRD) and was verified by transmission electron microscopy (TEM), mechanical testing, and rheological analysis. XRD analysis showed that the nanocomposite with the organoclay DMDA contained intercalated silicate layers, as also verified by TEM. The TEM analysis of the nanocomposites with TBHP exhibited intercalated/partially exfoliated clay dispersion. TKA, with a crowded alkyl environment, sheltered and hindered the intercalation of polymer chains through the silicate layers. In comparison to pure LLDPE, nanocomposites with a 33–41% higher Young's modulus, 16–9% higher tensile strength, and 75–144% higher elongation at break were produced with DMDA and TBHP, respectively (at 5 wt % organoclay). The storage modulus increased by 807–1393%, and the dynamic viscosity increased by 196–339% with respect to pure LLDPE at low frequencies for the samples with DMDA and TBHP (at 5 wt % organoclay). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis of epoxy encapsulated organoclay nanocomposite latex via phase inversion emulsification and its gas barrier property

Waterborne epoxy–clay nanocomposites were prepared by encapsulation of organoclays in epoxy latex particles via phase inversion emulsification. The organoclays were exfoliated in the epoxy backbone before compounding with a hardener and subsequently dispersing in water. The encapsulation of clay platelets into the waterborne epoxy latex particle resulted in an exponential increase in particle size, from 5 to 10 times at a clay loading of only 1–2 wt%, respectively. The XRD patterns and TEM images show that clay platelets were well intercalated and exfoliated in the epoxy matrix. The gas barrier performance of the epoxy–clay nanocomposite strongly depended on the kind of organoclay. The best oxygen barrier efficiency was approximately 14% at 2 wt% clay loading.     

Thermal and Barrier Properties of Organoclay-filled Polysulfone Nanocomposites

Organo-modified fluorohectorite (OFH) clay-filled polysulfone (PSf) nanocomposites were prepared by a solution casting method. The dispersion of OFH clay in PSf nanocomposites was investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Thermal analysis revealed that incorporation of organoclay increased the thermal stability and glass transition temperature (T_g) of nanocomposites. The barrier properties of the nanocomposites studied were found to be significantly improved. It is worth mentioning that the improved thermal stability and barrier performance of these nanocomposites with the addition of organoclay in PSf matrix obviously offers immense potential in industrial and automobile applications.     

Polyamide- and polycarbonate-based nanocomposites prepared from thermally stable imidazolium organoclay

This paper explores the possible advantages of the more thermally stable imidazolium-based organoclay over a more conventional ammonium-based organoclay for facilitating exfoliation and minimizing polymer matrix degradation in melt blended polyamide 6 (PA-6) and polycarbonate (PC) nanocomposites. The thermal stability of the two organoclays was evaluated by TGA analyses. The extent of clay exfoliation was judged by analysis of the morphology and tensile modulus of these nanocomposites formed using a DSM Microcompounder, while the extent of color formation and molecular weight change were used to evaluate polymer matrix degradation. For PA-6 and PC nanocomposites, the use of the imidazolium organoclay only produced slight differences in both exfoliation and molecular weight change, although the imidazolium organoclay is remarkably more thermally stable than the ammonium organoclay.     

Preparation and Properties of Ethylene Vinyl Acetate (EVA)/Organoclay/Compatibilizer Nanocomposites: Effects of Organoclay Loading and Methyl Ethyl Ketone

Ethylene vinyl acetate (EVA)/organoclay/compatibilizer nanocomposites were produced using a melt compounding technique in an internal mixer, Haake Rheometer, at 120°C and 50 rpm rotor speed. Effects of organoclay loading (from 2 to 10 phr—parts per hundred of resin and methyl ethyl ketone (MEK), used as a compatibilizer, on the processing properties, tensile properties, morphology, thermal degradation, and water absorption behavior of EVA/organoclay nanocomposites were studied. Results indicate that the presence of organoclay increase the processing torque, tensile properties, thermal degradation, and resistance to water absorption. The optimum organoclay loading was achieved at 2 phr. This was caused by the dispersion state of individual silicate layers (intercalation/exfoliation) in EVA matrix. The intercalation/exfoliation structure affects the properties of EVA/organoclay nanocomposites as evidenced from the morphology studies such as x-ray diffraction (XRD) and transmission electron microscopy (TEM) evaluation. The addition of MEK has the ability to improve the tensile properties, thermal degradation, and slightly reduces the resistance of water permeation of EVA/organoclay nanocomposites. The enhanced properties were seen as a result of the better matrix and filler interaction. The EVA/organoclay/MEK nanocomposites shows better intercalation/exfoliation of individual silicate layers in the EVA matrix as indicated by TEM. Moreover, the XRD evaluation shows that intercalation/exfoliation of the organoclay was formed in the EVA matrix.     

Preparation and characterization of new melt compounded copolyamide nanocomposites

In this work new copolyamide-layered silicate nanocomposites were prepared by melt compounding using a commercial polyamide 6-based copolymer, with a partially aromatic structure, as thermoplastic matrix. This copolyamide, having a lower melting point and improved mechanical and barrier properties respect to the homopolymer, appears an interesting material for producing nanocomposite packaging films. Hybrids with different organoclay loadings were produced by a twin-screw extruder using different extrusion rates, in order to point out the effects of both processing conditions and hybrid composition on morphology (silicate dispersion and exfoliation, orientation, matrix crystallinity) of nanocomposites. All melt-intercalated samples were submitted to structural (TEM and XRD), thermal and dynamic mechanical measurements. The performed analyses have evidenced that all hybrids exhibit mixed intercalated/exfoliated morphology and that the extent of exfoliation increases with both clay amount and extrusion rate used. Moreover, it was pointed out that the silicate nano-scale dispersion significantly affects the crystalline morphology of copolyamide matrix, stabilizing the γ-crystal phase, and the dynamic mechanical response of the hybrids, whose storage and loss moduli values result sensibly higher than those corresponding to the neat matrix.     

Development of high‐performance epoxy/clay nanocomposites by incorporating novel phosphonium modified montmorillonite

Novel organoclays were synthesized by several kinds of phosphonium cations to improve the dispersibility in matrix resin of composites and accelerate the curing of matrix resin. The possibility of the application for epoxy/clay nanocomposites and the thermal, mechanical, and adhesive properties were investigated. Furthermore, the structures and morphologies of the epoxy/clay nanocomposites were evaluated by transmission electron microscopy. Consequently, the corporation of organoclays with different types of phosphonium cations into the epoxy matrix led to different morphologies of the organoclay particles, and then the distribution changes of silicate layers in the epoxy resin influenced the physical properties of the nanocomposites. When high‐reactive phosphonium cations with epoxy groups were adopted, the clay particles were well exfoliated and dispersed. The epoxy/clay nanocomposite realized the high glass‐transition temperature (T_g) and low coefficient of thermal expansion (CTE) in comparison with those of neat epoxy resin. On the other hand, in the case of low‐reactive phoshonium cations, the dispersion states of clay particles were intercalated but not exfoliated. The intercalated clay did not influence the T_g and CTE of the nanocomposite. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Poly(amide‐imide)/organoclay nanocomposites using glycine as a natural amino acid: study on fire and thermal behavior

In the present study, new functional poly(amide‐imide)/organoclay nanocomposite films were successfully fabricated through the solution intercalation technique. New poly(amide‐imide) (PAI) containing glycine was synthesized via solution polycondensation of 1,1',3,3'‐tetraoxo(5,5'‐biisoindoline‐2,2'‐diyl)diacetic acid with 4,4′‐diaminodiphenylsulfone. The synthesized PAI was characterized by ¹H NMR, Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography, elemental analysis and inherent viscosity. Then, PAI/organoclay nanocomposite films containing 4 and 8 wt% of organoclay were prepared via solution intercalation through blending of organoclay 30B with the PAI solution. The nanostructures and properties of the PAI/organoclay were investigated using FTIR spectroscopy, XRD, transmission electron microscopy (TEM), TGA, DSC and microscale combustion calorimetry. XRD and TEM revealed the good dispersion of organoclay in the polymer matrix. TGA indicated that the addition of organoclay into the PAI matrix increases the thermal decomposition temperatures and char yields of the nanocomposites. Organoclay shows a positive effect in improving the flame retardancy of the PAI, reflecting the decrease in heat release rate, the total heat release and the heat release capacity of the PAI nanocomposites, while the thermal stability of the PAI nanocomposites only increased slightly compared with the neat polymer. © 2013 Society of Chemical Industry     

Epoxy layered-silicate nanocomposites

Polymer layered-silicate nanocomposites have attracted a lot of attention because of impressive enhancements of polymeric properties. In this research, both commercially available and synthesized organolayered silicates, which are compatible with the epoxy resins, were used to make epoxy nanocomposites. The epoxy resin used in this research includes Epon 862/curing agent W (the aerospace epoxy resin), the Epon 828/Epi-Cure curing agent 8290-Y-60 (used as the primer layer for corrosion prevention in aircraft coating), and Epon 828/Jeffamine D400. The morphology of the nanocomposites was characterized using wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The morphology development for the aerospace epoxy-organoclay nanocomposite was monitored through in situ SAXS and analyzed. The solvent absorption of the exfoliated aerospace epoxy-organoclay nanocomposite in acetone was examined, and the diffusion coefficients of solvent in the nanocomposites were reduced. The organoclay/Epon 828/Y-60 and organoclay/Epon 828/D400 nanocomposite were used to make coatings on an Al surface. The anticorrosion properties of the nanocomposite coating were evaluated and discussed.     

Effect of clay content and clay/surfactant on the mechanical, thermal and barrier properties of polystyrene/organoclay nanocomposites

In the present paper, three ammonium salts namely, tetraethylammonium bromide (TEAB), tetrabutylammonium bromide (TBAB), and cetyltrimethylammonium bromide (CTAB) were employed to prepare organoclay by cation exchange process. Polystyrene (PS) /clay nanocomposites were prepared by melt blending using commercial nanoclay and organoclays prepared using above mentioned salts. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis indicated that the modified clays were intercalated and/or exfoliated into the polystyrene matrix to a higher extent than the commercial nanoclay. Further, amongst the modified organoclays, TBAB modified clay showed maximum intercalation of clay layers and also exfoliation to some extent into the polystyrene matrix. TEM micrograph exhibited that TBAB modified clay had the best nanoscale dispersion with clay platelet thickness of ∼6–7 nm only. The mechanical properties of the nanocomposites such as tensile, flexural and izod impact strength were measured and analyzed in relation to their morphology. We observed a significant improvement in the mechanical properties of polystyrene/clay nanocomposites prepared with modified clays as compared to commercial organoclay, which followed the order as; PS/TBAB system > PS/CTAB system > PS/TEAB system. Thermogravimetric analysis (TGA) demonstrated that T₁₀, T₅₀ and Tmax were more in case of polystyrene nanocomposites prepared using modified organoclays than nanoclay [nanolin DK4] and maximum being in the case of PS/CTAB system. The results of Differential Scanning Calorimetry (DSC) confirmed that the glass transition temperature of all the nanocomposites was higher as compared to neat polystyrene. The nanocomposites having 2% of TBAB modified clay showed better oxygen barrier performance as compared to polystyrene.     

A processing-induced clay dispersion and its effect on the structure and properties of polyamide 6

The nanostructures and morphologies of polyamide 6 (PA6)/organoclay nanocomposites prepared by melt compounding have been studied by using X-ray diffraction (XRD) and transmission electron microscopy (TEM). A combination of XRD and TEM indicates that an exfoliated clay morphology dominates at low clay loadings (≤5 wt%) and a mixture of intercalated and exfoliated structures exists at high clay concentrations. It is worth noting, however, that optical microscopy (OM) even shows the presence of large clay agglomerates in samples with higher clay contents. OM images further present an overview of an uneven clay distribution due to the effect of injection molding. The crystalline structure of PA6 is greatly affected by this unevenness in the processing-induced clay dispersion, as evidenced by differential scanning calorimetry (DSC). The thermal dynamic and mechanical properties of PA6 and the nanocomposites have been investigated as a function of clay concentration. The tensile tests show that the degree of dispersion of the nanoclay within the polymer matrix plays a vital role in property improvement. Copyright © 2004 Society of Chemical Industry     

Morphology and mechanical and viscoelastic properties of rubbery epoxy/organoclay montmorillonite nanocomposites

The morphology and mechanical and viscoelastic properties of rubbery epoxy/organoclay montmorillonite (MMT) nanocomposites were investigated with wide‐angle X‐ray scattering (WAXS), transmission electron microscopy (TEM), tensile testing, and dynamic mechanical thermal analysis. An ultrasonicator was used to apply external shearing forces to disperse the silicate clay layers in the epoxy matrix. The first step of the nanocomposite preparation consisted of swelling MMT in a curing agent, that is, an aliphatic diamine based on a polyoxypropylene backbone with a low viscosity for better diffusion into the intragalleries. Then, the epoxy prepolymer was added to the mixture. Better dispersion and intercalation of the nanoclay in the matrix were expected. The organic modification of MMT with octadecylammonium ions led to an increase in the initial d‐spacing (the [d₀₀₁] peak) from 14.4 to 28.5 Å, as determined by WAXS; this indicated the occurrence of an intercalation. The addition of 5 phr MMTC18 (MMT after the modification) to the epoxy matrix resulted in a finer dispersion, as evidenced by the disappearance of the diffraction peak in the WAXS pattern and TEM images. The mechanical and viscoelastic properties were improved for both MMT and MMTC18 nanocomposites, but they were more pronounced for the modified ones. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 103: 3547–3552, 2007     

Polyimide nanocomposites prepared from high-temperature, reduced charge organoclays

Montmorillonite clays modified with the dihydrochloride salt of 1,3-bis(3-aminophenoxy)benzene (APB) were used in the preparation of polyimide/organoclay hybrid films. Organoclays with varying surface charge based upon APB were prepared and examined for their dispersion behavior in the polymer matrix. High molecular weight poly(amide acid) solutions were prepared in the presence of the organoclays. Films were cast and subsequently heated to 300 °C to cause imidization. The resulting nanocomposite films, containing 3 wt% of organoclay, were characterized by transmission electron microscopy and X-ray diffraction. The clay's cation exchange capacity (CEC) played a key role in determining the extent of dispersion in the polyimide matrix. Considerable dispersion was observed in some of the nanocomposite films. The most effective organoclay was found to have a CEC of 0.70 meq/g. Nanocomposite films prepared with 3-8 wt% of this organoclay were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and thin-film tensile testing. High levels of clay dispersion could be achieved even at the higher clay loadings. Results from mechanical testing revealed that while the moduli of the nanocomposites increased with increasing clay loadings, both strength and elongation decreased.     

Surface morphology,thermomechanical and barrier properties of poly(ether sulfone)‐toughened epoxy clay ternary nanocomposites

Poly(ether sulfone) (PES)‐toughened epoxy clay ternary nanocomposites were prepared by melt blending of PES with diglycidyl ether of bisphenol A epoxy resin along with Cloisite 30B followed by curing with 4,4′‐diaminodiphenylsulfone. The effect of organoclay and thermoplastic on the fracture toughness, permeability, viscoelasticity and thermomechanical properties of the epoxy system was investigated. A significant improvement in fracture toughness and modulus with reduced coefficient of thermal expansion (CTE) and gas permeability were observed with the addition of thermoplastic and clay to the epoxy system. Scanning electron microscopy of fracture‐failed specimens revealed crack path deflection and ductile fracture without phase separation. Oxygen gas permeability was reduced by 57% and fracture toughness was increased by 66% with the incorporation of 5 phr clay and 5 phr thermoplastic into the epoxy system. Optical transparency was retained even with high clay content. The addition of thermoplastic and organoclay to the epoxy system had a synergic effect on fracture toughness, modulus, CTE and barrier properties. Planetary ball‐milled samples gave exfoliated morphology with better thermomechanical properties compared to ultrasonicated samples with intercalated morphology. Copyright © 2010 Society of Chemical Industry     

Properties of novel epoxy/clay nanocomposites prepared with a reactive phosphorus-containing organoclay

In this study, a reactive phosphorus-containing organoclay (RPC) was successfully prepared through the cationic exchange reaction of sodium montomorillonite clay with hexyltriphenylphosphonium bromide and surface modification by grafting it with glycidyloxypropyltrimethoxy silane. It is characterized using X-ray diffraction (XRD) and Fourier transform IR (FTIR) measurements. A series of novel epoxy/clay nanocomposites (ERPC) was then prepared with a selected epoxy resin and varying amounts of RPC. The results of XRD and TEM of the nanocomposites showed that the RPC particles were well dispersed in the epoxy matrix with a highly exfoliated structure due to the presence of the reactive epoxide group of RPC. The as-prepared epoxy/RPC nanocomposites (ERPC) were thermally stable up to 388 °C. Thermal stability was increased by increasing the RPC content as indicated by the corresponding activation energies (E_a) and the integral procedural decomposition temperatures (IPDT). Furthermore, the storage modulus in the glass state of the nanocomposites was dramatically increased with the increase in RPC content. In addition, the large increment of limiting oxygen index (LOI) which was 11 units higher than that of the neat epoxy indicates that an extraordinary enhancement of flame retardancy was obtained from the nanocomposite containing 5 wt% of RPC.     

Effect of exfoliation and dispersion on the yield behavior of melt‐compounded polyethylene–montmorillonite nanocomposites

The yield behavior of melt‐mixed nanocomposites containing 5 wt % organically modified montmorillonite in matrices of a linear low‐density polyethylene (LLDPE) or a modified polyethylene was studied as a function of the temperature and strain rate. In the melt‐mixed LLDPE nanocomposite, the montmorillonite showed a slight increase in the clay spacing, which suggested that the clay was at best intercalated. Transmission electron microscopy (TEM) images showed that the dispersion in this nanocomposite was poor. The use of the modified polyethylene promoted exfoliation of the clay tactoids in the nanocomposite, as assessed by X‐ray diffraction and TEM. In both nanocomposites, the yield mechanisms were insensitive to the addition of the organoclay, even though modest increases in the modulus were produced. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3044–3049, 2006     

Mechanical and physical properties of polymer‐based nanocomposites containing different types of clay

Epoxy‐clay nanocomposites based on diglycidyl ether of bisphenol A (DGEBA) epoxy reinforced with 2 wt% of four different types of clay were prepared by high shear mixing (HSM) technique. The resultant nanocomposites were investigated to determine the effects of clay addition and clay types on their mechanical, thermal, and physical properties. The XRD and TEM analyses revealed that good dispersions of nanoclay within the epoxy matrix have been achieved especially for the samples prepared with I.30E clay where a combination of disordered intercalated and exfoliated morphology was observed. The structure of samples synthesized with other types of clay was dominated by intercalated morphologies. The tensile results illustrated that the nanocomposite containing I.30E clay has the best mechanical properties as compared to other nanocomposites. This is mainly due to better dispersion of I.30E nanoclay in the epoxy matrix for this nanocomposite. The increase or decrease in the glass transition temperatures of nanocomposites were found to be dependent on the type of clay used. The effect of clay addition on the barrier properties was examined using water exposure test which demonstrated that the addition of 2% of I.30E and C10A clays resulted in 60% reduction in diffusivity. Noticeable reduction in maximum water uptake was also observed for all nanocomposites. The improvement in these physical properties was attributed to the tortuosity effect, where water molecules have to move around clay layers during diffusion in nanocomposites. POLYM. COMPOS., 36:1998–2007, 2015. © 2014 Society of Plastics Engineer