Dynamic Mechanical Analysis Studies Research Articles

Effect of Dispersion Conditions on the Thermal and Mechanical Properties of Carbon Nanofiber–Polyester Nanocomposites

In this study, sonication dispersion technique was employed to infuse 0.1–0.4 wt.% carbon nanofibers (CNFs) into polyester matrix to enhance thermomechanical properties of resulting nanocomposites. The effect of dispersion conditions has been investigated with regard to the CNF content and the sonication time. X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) micrographs revealed excellent dispersion of 0.2 wt.% CNF infused in polyester, resulting in enhanced mechanical responses. Polyester with 0.2 wt.% CNF samples resulted in 88% and 16% increase in flexural strength and modulus, respectively, over the neat one. Quasi-static compression tests showed similar increasing trend with addition of CNF. Fracture morphology study of tested samples revealed relatively rougher surface in CNF-loaded polyester compared to the neat due to better interaction between the fiber and the matrix. Dynamic mechanical analysis (DMA) study exhibited about 35% increase in the storage modulus and about 5 °C increase in the glass transition temperature (Tg). A better thermal stability in the CNF-loaded polyester was observed from the thermogravimetric analysis (TGA) studies. Best results were obtained for the 0.2 wt.% CNF loading with 90 mins of sonication and 50% sonication amplitude. It is recommended that this level of sonication facilitates suitable dispersion of the CNF into polyester matrices without destroying the CNF's structure.

Effect of electroceramic particles on damping behaviour of aluminium hybrid composites produced by ultrasonic cavitation and mechanical stirring

Abstract In this study, electroceramics PBN and PLZT along with SiC were included in Al–3.96 wt.% Mg (A514.0) master alloy. Ultrasonic cavitation (UST) and mechanical stirring (MS) were employed to improve wettability and dispersion during casting. Two composite systems were produced: PBN system (5 wt.% PBN + 1 wt.% SiC and 15 wt.% PBN + 1 wt.% SiC) and the PLZT system (follows the same designation). The influence of fabrication method on the microstructures, particle distribution and wettability as well as electroceramic impact on dynamo-mechanical properties of prepared composites were investigated. Optical microscope (OM) and scanning electron microscope (SEM) results indicate that the processing technique was effective as it promoted wettability and homogeneous dispersion of particles throughout the Al matrix. Dynamic mechanical analysis (DMA) study of the composites demonstrated that the addition of the functional particles to the Al alloy matrix improved damping capacity ( Tan δ ) at 200 °C. The composites exhibited an increase in Tan δ of 24.3 ± 0.3% and 91.4 ± 0.2% for 5 and 15 wt.% PBN + 1 wt.% SiC and an increase of 19.7 ± 0.5% and 42.5 ± 0.3% for 5 and 15 wt.% PLZT + 1 wt.% SiC, respectively, when compared to the aluminium alloy matrix.

Mechanical properties and creep behavior of rotationally moldable linear low density polyethylene-fumed silica nanocomposites

Rotationally moldable linear low density polyethylene (LLDPE) is one of the most popular materials used for rotational molding. Yet, incorporation of additives is necessary to improve the mechanical, visco-elastic, thermal as well as melt flow properties of LLDPE. In this article, the influence of fumed silica (FS) nanoparticles on the mechanical properties viz. tensile, flexural, and impact strengths of rotationally moldable LLDPE is investigated. The microstructural studies using SEM were conducted to study the dispersion of FS in LLDPE and correlated with the mechanical properties of the nanocomposites. Dynamic mechanical analysis (DMA) were also carried out to find the time–temperature dependent mechanical properties viz. storage modulus (E'), loss modulus (E”), and tan delta between 1 and 8 wt% of FS. DMA studies were extended to perform accelerated stepped isothermal creep studies to find out the influence of FS in creep strains. POLYM. COMPOS., 38:421–430, 2017. © 2015 Society of Plastics Engineers

Finite element analysis of the residual thermal stresses on functionally gradated dental restorations

The aim of this work was to study, using the finite element method (FEM), the distribution of thermal residual stresses arising in metal–ceramic dental restorations after cooling from the processing temperature. Three different interface configurations were studied: with conventional sharp transition; one with a 50% metal–50% ceramic interlayer; and one with a compositionally functionally gradated material (FGM) interlayer. The FE analysis was performed based on experimental data obtained from Dynamic Mechanical Analysis (DMA) and Dilatometry (DIL) studies of the monolithic materials and metal/ceramic composites.Results have shown significant benefits of using the 50% metal–50% ceramic interlayer and the FGM interlayer over the conventional sharp transition interface configuration in reduction of the thermal residual stress and improvement of stress profiles. Maximum stresses magnitudes were reduced by 10% for the crowns with 50% metal–50% ceramic interlayer and by 20% with FGM interlayer. The reduction in stress magnitude and smoothness of the stress distribution profile due to the gradated architectures might explain the improved behavior of these novel dental restorative systems relative to the conventional one, demonstrated by in-vitro studies already reported in literature.

Hybrid Nanocomposites – A Review

Since the last ten years, research happenings in the field of nanomaterials have been increased dramatically. Materials scientists and researchers have realized that the mechanical properties of materials can be altered at the fundamental level, i.e. at the atomic-scale. Carbon nanotubes have been well recognized as nanostructural materials that can be used to modify mechanical, thermal and electrical properties of polymer-based composite materials, because of their excellent properties and perfect atom arrangement. In geneal, scientific research related to the nanotubes and their co-related polymer based composites can be distinguished into four particular scopes: (i) production of high purity and well-regulated nanotubes, in terms of their size, length and chiral arrangement; (ii) enhancement of interfacial bonding strength between the nanotubes and their surrounding matrix; (iii) control of the dispersion properties and alignment of the nanotubes in nanotube/polymer composites and (iv) applications of the nanotube in real life. Research shows that addition of resin with nanoclays permits to retain stiffness without losing toughness, and also improving barrier and thermal properties. Dynamic Mechanical Analysis (DMA) studies revealed that filling the carbon nanotube into epoxy can produce a 90% enhancement in storage modulus and a 22°C increase in Tg. Addition of nanoclay and epoxy with nanotubes forms a hybrid nanocomposite.

Studies on novel tri-phthalonitrile phenyl polyhedral oligomeric silsesquioxane and the phthalonitrile–epoxy blends

A novel tri-phthalonitrile phenyl polyhedral oligomeric silsesquioxane (TPnPh-POSS) was synthesized from trisilanol phenyl POSS and 4-nitrophthalonitrile. The structure of the TPnPh-POSS monomer was characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The phthalonitrile monomer was thermally polymerized with various concentrations (3, 4, and 5 wt%) of 4,4′-diaminodiphenyl sulfone (DDS) as the curing agent. The curing behavior of the monomer was investigated by differential scanning calorimetry. The influence of the content of the curing additive on the polymer properties was studied. Blends of TPnPh-POSS and diglycidyl ether of bisphenol A (epoxy resin) were successfully prepared. The thermal and mechanical properties of these blends with DDS as curing agent were evaluated and compared with the neat epoxy resin. The thermal stability of the cured polymers and epoxy/TPnPh-POSS blends was studied by thermogravimetric analysis. Dynamic mechanical analysis and dielectric studies indicate the influence of TPnPh-POSS content on the relaxation behavior of the prepared blends. The blends exhibit high glass transition temperatures, high storage modulus, and increased thermal stability compared with the commercially available neat epoxy resin. Noncrystalline nature of the cured polymer (with 5 wt% of DDS) was confirmed by X-ray diffraction analysis. The cured polymer shows high flame retardancy, which improved with increase in the amount of the curing additive.

Greatly enhanced thermo‐oxidative stability of polybenzoxazine thermoset by incorporation of m‐carborane

ABSTRACTNovel polybenzoxazine precursor containing m‐carborane unit in the main‐chain has been firstly synthesized through click reaction of diazidomethyl m‐carborane (DAMC) and diacetylene bisbenzoxazine (DABB). Meanwhlie, the traditional polybenzoxazine precursor was also prepared through click reaction of diazidomethyl p‐benzene (DAPB) and DABB as a control. 1H NMR was used to confirm the structures of the monomers and the resulting polymers. FT‐IR and differential scanning calorimetry (DSC) were used to study the curing behavior of carborane‐containing benzoxazine polymer (CCBP). Dynamic mechanical analysis (DMA) study demonstrated that the cured CCBP had high storage moduli and high Tg. Thermogravimetric analysis (TGA) and ablation test showed that the cured CCBP had outstanding thermo‐oxidative stability. During thermal ablation of cured CCBP, organic material was degraded, and a passivation layer with oxidized m‐carboranes was formed, which prevented the underlying polymer from further degradation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 973–980

Molecular Dynamics Simulations and Hygrothermal Aging of Polyurea–POSS Nanocomposites

The long-term performance of any novel material in its working environment is an intriguing area of research. The combined effect of the moisture content (relative humidity) and temperature of the environment degrades the mechanical properties of polymer composites. In the first part of this manuscript, polyurea–polyhedral oligomeric silsesquioxane (POSS) nanocomposites are subjected to continuous hygrothermal cycling. The effects of prolonged hygrothermal aging on the mechanical performance of the composites are evaluated in terms of the change in tensile strength and elongation at failure. Aged composites are subjected to FTIR spectroscopy to study the chemical changes resulting from the hydrolysis of polyurea. In the second part, attempts are made to study the effect of the addition of POSS nanoreinforcement on the mechanical properties of the resulting composite materials using molecular dynamics (MD) simulations. Results obtained here show poor agreement between MD simulation results and results obtained using dynamic mechanical analysis studies. However, qualitatively, both simulation and experimental results exhibit similar effects due to addition of POSS nanoparticles on the mechanical properties of polyurea–POSS nanocomposites.

Internal stresses in the electrostriction phenomenon viewed through dynamic mechanical analysis studies conducted under electric field

A model for studying the mechanical internal stresses into dielectric materials is developed in the present work. The model takes into account the formalism of inclusions in continuous media. The dielectric material is assumed to be partitioned in different cubes which form a sizeable bulk material in such a way that a given cube can be of the dipolar phase and its neighbor can be of the same phase or the matrix. The behavior of the internal stresses promoted by the electrostriction phenomenon can be monitored by studying the behavior of both the misfit coefficient related to the strain misfit and the transfer of elastic energy process. The equations obtained through the here presented model are calculable using magnitudes from mechanical tests, in particular dynamic mechanical analysis, which is very sensitive to changes in the microstructure. Dynamic mechanical analysis as a function of the electric field is reported, perhaps for the first time in literature, for the study of dielectric materials, giving rise to a useful tool for studying the behavior of internal stresses in dielectric materials.

Hybrid Poly(aryl ether sulfone amide)s for Advanced Thermoplastic Composites

An organocatalytic approach to the depolymerization of poly(ethylene terephthalate) (PET) with selected nucleophiles generates high‐value terephthalate‐based monomers. These monomers are subjected to nucleophilic aromatic substitution (SNAr) polymerizations in order to circumvent many of the traditional drawbacks of unmodified materials such as poly(aryl ether sulfone)s (PESs). The synthesis and molecular characterization of novel poly(aryl ether sulfone‐amide)s (PAESAs) containing 10–30 wt% amide functionality are described. PAESAs containing 30 wt% amide are fabricated via extrusion and solvent casting for mechanical characterization. The mechanical behavior of the extruded PAESA is studied through dynamic mechanical analysis (DMA) and tension tests. The DMA studies are performed at a frequency of 1 Hz, in the temperature range of 22–275 °C, indicating a storage modulus of 2.77 ± 0.58 MPa at 30 °C. The glass transition temperature (Tg) of the material, as the temperature corresponding to tanδ peak, is measured to be 217.1 ± 1.7 °C, consistent with DSC measurements. The tension tests on extruded samples reveal a ductile fracture, evidenced with neck formation and propagation on the macroscale, and a rough fracture surface on the microscale. The yield strength of the sample is found to be 52.8 ± 9.2 MPa, with a ductility ranging from 6% to 11%. In contrast to extruded samples, the solvent‐cast PAESA samples fail in a brittle fashion, with relatively smooth fracture surface and no sign of necking. image

Toughening epoxy resin with blocked isocyanate containing soft chain

ABSTRACTA series of imidazole (MI) blocked 2,4‐toluene diisocyanate (TDI) with polyethylene glycol (PEG‐400) as soft segment (PEG‐MI‐b‐TDI) were synthesized for toughening and curing the bisphenol A type epoxy resin (E‐44). Fourier transform infrared (FTIR) spectrum indicates that the NCO groups of the isocyanate molecule are blocked with MI. For curing epoxy systems, elimination of epoxy group and the formation of urethane bonds were studied by FTIR spectroscopy. The results of mechanical property were shown that the tensile shear and impact strengths of neat MI and MI‐b‐TDI cured E‐44 are lower than those of PEG‐MI‐b‐TDI cured E‐44. Based on the scanning electron microscope studies, microstructure evolutions of the E‐44 cured by different curing agents were imaged. The mechanical, thermal, and dynamic mechanical properties were measured by universal testing machine, differential scanning calorimeter and dynamic mechanical analyzer (DMA). The toughness of E‐44 cured by PEG‐MI‐b‐TDI was effectively improved without sacrificing the tensile shear strength. Based on the DMA studies, the long soft chain of PEG brought in a noticeable lowering in the glass transition temperature (Tg). The glass transition temperature is near 165°C for the neat MI cured E‐44, which is higher than the Tgs of the other curing agents cured epoxy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41345.

Dielectric properties of modified graphene oxide filled polyurethane nanocomposites and its correlation with rheology

This study aims at investigating the dynamic mechanical, dielectric and rheological properties of reinforced polyurethane (PU) nanocomposites containing hydrophilic graphene oxide (GO) and/or hydrophobic modified graphene oxide (mGO) sheets. The organic modification of GO was performed with 4,4′-methylenebis (phenyl isocyanate) (MDI) and the samples were prepared by solvent mixing. We found that addition of mGO provides a more significant increase in the dielectric permittivity as compared to the addition of GO. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectroscopy demonstrate the more effective dispersion of thin exfoliated sheets of mGO in the PU matrix as compared to unmodified GO. This qualitative morphology observation is correlated with the quantitative results inferred from the dynamic mechanical analysis, rheology and dielectric studies. The viscoelastic Payne effect is noticed for all nanocomposites and the filler–filler and polymer–filler interactions are studied by applying the Kraus and Maier and Goritz models. The non-linear viscoelastic behavior of the PU nanocomposites is in good agreement with the Maier and Goritz model, which includes the effects of the adsorption/desorption of PU chains on the filler surface. The observed results underline the possibilities of PU composites with organically modified GO sheets in capacitor applications.

Investigation of accelerated aging behaviour of high performance industrial coatings by dynamic mechanical analysis

• Dynamic mechanical analysis (DMA) was used to study four different industrial topcoats. • T g varies widely depending on cure chemistry, composition and crosslink density. • Creep recovery is a critical factor for improved durability in topcoats. • Crosslink density and T g change considerably after artificial weathering. • DMA study gives valuable indications about the long-term performance properties. Dynamic mechanical analysis (DMA) represents one of the most important methods for understanding mechanical behaviour of surface coatings providing a valuable link between chemistry, morphology, and performance properties. In this work, dynamic mechanical properties of several high performance industrial coatings were studied extensively. Four commercially available topcoats namely alkyd modified polyurethane (PU), economy aliphatic PU, high performance aliphatic PU and epoxy modified polysiloxane were selected based on their cure chemistries, volume solids, and overall performance. DMA was used to determine elastic modulus, glass transition temperature ( T g ), crosslink density and creep behaviour of these coatings. DMA data were substantiated with mechanical and performance properties. Among the coatings, epoxy modified polysiloxane showed the highest T g of 65.6 °C as well as crosslink density value of 2.24 × 10 −3 mol/cc which was attributed to its superior mechanical and performance properties. In addition, topcoats were also subjected to artificial aging process in accelerated cyclic corrosion cabinet and QUV-weatherometer, respectively. The consequent changes in their physico-mechanical properties post exposure were also evaluated using DMA and correlated with other performance properties. After aging, the T g increased substantially for all the coatings irrespective of their exposure type. For example, T g of economy aliphatic PU increases from 38.4 °C to 52.9 °C and 51 °C after cyclic corrosion and UV-B weathering, respectively. However, crosslink densities either increased or decreased depending on the type of exposure and cure chemistries. These changes were corroborated using the Fourier transform infrared spectroscopy findings. The outcome of this study is expected to generate new insights into the behaviour of these coatings under dynamic mechanical stress and its relation with long term performance properties.

DMA and DSC studies of accelerated aged parchment and vegetable-tanned leather samples

The aim and the novelty of this work was the use of both dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC), in water and in dry state, for the investigation of the effects of temperature and relative humidity on degradation of recently manufactured parchments and vegetable-tanned leathers. The materials were subjected to accelerated ageing under action of heat and moisture for progressively increasing time lengths. The studies have proved that accelerated ageing causes a progressive decrease of the temperature of denaturation in water excess, but has no or minor effect on that in dry state. Also, under same ageing conditions parchments undergo a greater degree of deterioration than leathers, as evidenced by a more dramatic change in the DSC peaks (in water) and in the shrinkage curves (DMA). The results can be interpreted as a partial gelatinization occurring in the thermal conditions used for accelerated ageing. The paper presents the advantage of using both techniques, namely that DSC results can assist in interpretation of the DMA curves and that the good correlation of denaturation temperatures obtained by DSC and DMA ascertain these values. Such studies can be useful for understanding the processes that take place on natural ageing of historical parchments and leathers, as well as for establishing proper conditions of their storage.

Dynamically vulcanized high impact polystyrene/high vinyl polybutadiene rubber composites compatibilized by styrene–butadiene–styrene block copolymer

Thermoplastic vulcanizates (TPVs) based on high impact polystyrene (HIPS)/high vinyl polybutadiene rubber (HVPBR) composites were prepared by dynamic vulcanization, and then compatibilized by styrene–butadiene–styrene (SBS) block copolymer. The effects of SBS compatibilizer on mechanical properties, Mullins effect, morphological and dynamic mechanical properties of the TPVs were investigated systematically. Experimental results indicated that SBS had an excellent compatibilization effect on the dynamically vulcanized HIPS/HVPBR composites. Compared with those of HIPS/HVPBR composite, the tensile strength, elongation at break and tearing strength of HIPS/HVPBR composite with 12 phr SBS incorporation were improved by about 163%, 312% and 67%, respectively. Mullins effect results showed that the compatibilized HIPS/HVPBR TPVs had relatively lower residual deformation and internal friction loss than those of HIPS/HVPBR composites, indicating the improvement of elastic reversibility. Morphology studies showed that the interface interaction of the TPVs was enhanced and the particle sizes of the dispersed phase were decreased with the incorporation of SBS compatibilizer. Dynamic mechanical analysis studies showed that the Tg s of HIPS and HVPBR phases were slightly shifted toward low temperature with the incorporation of SBS, which indicates the significant improvement of the compatibility.

Influence of monomeric and polymeric structure on the physical properties of thermoplastic polyesters derived from hydroxy fatty acids

The physical properties of three vegetable oil derived medium and long chain poly(ω‐hydroxy fatty ester)s (P(Me‐ω‐OHFA)s), namely poly(ω‐hydroxynonanoate) [P(Me‐ω‐OHC9)], poly(ω‐hydroxytridecanoate) [P(Me‐ω‐OHC13)] and poly(ω‐hydroxyoctadecanoate) [P(Me‐ω‐OHC18)] (n = 8, 12 and 17, respectively), of the [−(CH2)n−COO–]x polyester homologous series are presented. The effect of Mn (Mn 10–40 kg mol−1) and n on the crystal structure and thermal and mechanical properties of the P(Me‐ω‐OHFA)s were investigated by wide‐angle X‐ray diffraction (WAXD), TGA, DSC, dynamic mechanical analysis (DMA) and tensile analysis and are discussed in the context of the [−(CH2)n−COO–]x polyester homologous series, contrasted with linear polyethylene (PE). For all P(Me‐ω‐OHFA)s the WAXD data indicated an orthorhombic crystal phase reminiscent of linear PE with crystallinity (Xc = 50%−80%) depending strongly on Mn. The glass transition temperature and Young's modulus for P(Me‐ω‐OHFA)s increased with Xc. The DSC, DMA and TGA studies for P(Me‐ω‐OHFA)s (n = 8, 12 and 17) indicated strong correlations between the melting, glass transition and thermal degradation behavior and n. The established predictive structure relationships can be used for the custom engineering of polyester materials suitable for specialty and commodity applications. © 2014 Society of Chemical Industry

Hyperbranched polymers containing oxazoline monomers and succinic anhydride: Applications in fast drying, low solvent coating formulations

Melt-polycondensation of succinic acid anhydride with oxazoline-based diol monomers gave hyperbranched polymers with carboxylicacids terminal groups. 1 H NMR and quantitative 13 C NMR spectroscopy coupled with DEPT-135 13 C NMR experiment showed high degrees of branching (over 60%). Esterification of the acid end groups by addition of citronellol at 160 °C produced novel white spirit soluble resins which were characterized by Fourier transform-infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Blends of the new hyperbranched materials with commercial alkyd resins resulted in a dramatic, concentration dependent drop in viscosity. Solvent-borne coatings were formulated containing the hyperbranched polymers. Dynamic mechanical analysis studies revealed that the air drying rates of the new coating systems were enhanced compared with identical formulations containing only commercial alkyd resins.

Influence of applying microwave radiation on the LDPE/MWCNTs nanocomposite

Low density polyethylene (LDPE) and multiwall carbon nanotube (MWCNT) nanocomposites of varying MWCNT contents were prepared by melt blending and compression molding. The sample sheets were exposed to microwave irradiation and the effect on chemical, mechanical, and thermal properties as well as the sheets' morphology were determined and compared with that of nonirradiated samples with similar compositions. The percentage crystallinity of the LDPE/MWCNT nanocomposites declined after irradiation due to the degradation of polymeric chains. However, the melting temperature was hardly changed. The chemical degradation due to irradiation was also verified from the increase in the carbonyl index as determined from the Fourier transformed‐infrared spectroscopy study and the decline in the storage modulus of the dynamic mechanical analysis study. The microcalorimetry study revealed that the MWCNT nanofillers were effectively acting as a heat absorption shield by reducing the heat release rate of polymer during combustion. The Raman spectra and scanning electron microscopy photographs demonstrated improved interaction of MWCNT with the LDPE matrix after microwave irradiation. POLYM. COMPOS., 35:2036–2042, 2014. © 2014 Society of Plastics Engineers

Dynamic-mechanical analysis of MWNTs-filled PC/ABS blends

In a systematic manner, the roles of MWNTs as filler and styrene acrylonitrile copolymer-graft-maleic anhydride (SAN-MA) as compatibilizer, individually and together, on dynamic-mechanical behavior of polycarbonate (PC)-rich/acrylonitrile butadiene styrene terpolymer (ABS) blend were studied. The investigations were performed using small-scale mixing in a one-step procedure with a fixed MWNTs content of 0.75 wt% and a blend composition of PC/ABS = 70/30 w/w. PC/SAN blends and nanocomposites as simpler model system for PC/ABS were also studied to reveal the role of the rubbery polybutadiene (PB) fraction. It is found that the tendency of MWNTs to localize within the PC component in compatibilized PC/ABS was lower than in compatibilized PC/SAN blends. Dynamic mechanical analysis (DMA) revealed the dual role of SAN-MA as blend compatibilizer and also promoter of MWNTs migration towards PC, where SAN-MA to MWNTs weight ratio varied between 1 and 4. At the compatibilizer/MWNTs weight ratio of 1, MWNTs localized in PC component of the blends whereas increasing the compatibilizer/MWNTs ratio to 4 led to migration of MWNTs toward SAN or ABS component. In DMA studies, loss modulus normalization of the nanocomposites revealed the coexistence of mobilized and immobilized regions within the nanocomposite structure, as a result of MWNTs and compatibilizer loading. POLYM. ENG. SCI., 54:2696–2706, 2014. © 2014 Society of Plastics Engineers

Ionic elastomers based on carboxylated nitrile rubber (XNBR) and magnesium aluminum layered double hydroxide (hydrotalcite)

The presence of carboxyl groups in carboxylated nitrile butadiene rubber (XNBR) allows it to be cured with dif- ferent agents. This study considers the effect of crosslinking of XNBR by magnesium aluminum layered double hydroxide (MgAl-LDH), known also as hydrotalcite (HT), on rheometric, mechano-dynamical and barrier properties. Results of XNBR/HT composites containing various HT loadings without conventional curatives are compared with XNBR com- pound crosslinked with commonly used zinc oxide. Hydrotalcite acts as an effective crosslinking agent for XNBR, as is particularly evident from rheometric and Fourier transform infrared spectroscopy (FTIR) studies. The existence of ionic crosslinks was also detected by dynamic mechanical analysis (DMA) of the resulting composites. DMA studies revealed that the XNBR/HT composites exhibited two transitions - one occurring at low temperature is associated to the Tg of elas- tomer and the second at high temperature corresponds to the ionic transition temperature Ti. Simultaneous application of HT as a curing agent and a filler may deliver not only environmentally friendly, zinc oxide-free rubber product but also ionic elastomer composite with excellent mechanical, barrier and transparent properties.