Poly(ethylene‐co‐vinyl acetate)/calcium phosphate nanocomposites: Thermo mechanical and gas permeability measurements

Poly(ethylene‐co‐vinyl acetate) (EVA)/Calcium phosphate nanocomposites were prepared by melt mixing in a Brabender plasticoder. Nanoparticles of calcium phosphate were synthesized by the polymer‐mediated synthesis and characterized by X‐ray diffractometry and transmission electron microscopy. Mechanical properties such as tensile strength, tensile modulus, tear strength, etc., were measured with respect to the filler loading. Thermal stability of the composites under nitrogen atmosphere was also measured. The composites showed better thermal stability due to the nanoreinforcement. Oxygen gas permeability of the composites showed considerable decrease due to tortuous path created by the nanofillers. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers     

Fabrication,characterization, and properties of poly(ethylene‐co‐vinyl acetate)/magnetite nanocomposites

Poly(ethylene‐co‐vinyl acetate) (EVA)/magnetite (Fe₃O₄) nanocomposite was prepared with different loading of Fe₃O₄ nanoparticles. The mixing and compounding were carried out on a two‐roll mixing mill and the sheets were prepared in a compression‐molding machine. The effect of loading of nanoparticles in EVA was investigated thoroughly by different characterization technique such as transmission electron microscopy (TEM), X‐ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), limiting oxygen index (LOI), and technological properties. TEM analysis showed the uniform dispersion of filler in the polymer matrix and the dispersion of filler decreased with increase in filler content. XRD of the nanocomposite revealed the more ordered structure of the polymer chain. An appreciable increase in glass transition temperature was observed owing to the restricted mobility of Fe₃O₄‐filled EVA nanocomposite. TGA and flame resistance studies indicated that the composites attain better thermal and flame resistance than EVA owing to the interaction of filler and polymer segments. Mechanical properties such as tensile strength, tear resistance, and modulus were increased for composites up to 7 phr of filler, which is presumably owing to aggregation of Fe₃O₄ nanoparticle at higher loading. The presence of Fe₃O₄ nanoparticles in the polymer matrix reduced the elongation at break and impact strength while improved hardness of the composite than unfilled EVA. The change in technological properties had been correlated with the variation of polymer–filler interaction estimated from the swelling behavior. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40116.     

Cellulose nanofibres and cellulose nanowhiskers based natural rubber composites: Diffusion,sorption, and permeation of aromatic organic solvents

This article investigates the transport behavior of three aromatic organic solvents, viz. benzene, toluene, and p‐xylene in natural rubber nanocomposite membranes containing cellulose nanofibres (CNFs) and cellulose nanowhiskers (CNWs) isolated from bamboo pulp. The solvent molecules act as molecular probes to study the diffusion, sorption, and permeation through the nanocomposites, and provide information on the nanocomposite structure and matrix–filler interactions. Both the nanocelluloses were found to decrease the uptake of aromatic solvents in nanocomposite membranes, but the effect was more significant in the case on nanofibers compared to nanowhiskers. Furthermore, the uptake decreased with increased penetrant size; being the highest for benzene and the lowest for p‐xylene. Transport parameters such as diffusion coefficient, sorption coefficient, and permeation coefficient have been calculated. Comparison of the experimental values of equilibrium solvent uptake with the predicted values indicated that both the nanocelluloses have restricted the molecular mobility at the interphase and thereby decreased the transport of solvents through the materials; being more significant for nanofibers. The results showed that both the used cellulosic nanomaterials act as functional additives capable of manipulating and tailoring the transport of organic solvents through elastomeric membranes, even at concentrations as low as 2.5 wt %. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Preparation and characterization of chitosan/α‐zirconium phosphate nanocomposite films

Nano‐fillers play an important role in the final structure and properties of nanocomposites. The objective of the work presented here was to prepare nanocomposite films of chitosan/α‐zirconium phosphate using a casting process, with α‐zirconium phosphate (α‐ZrP) as nano‐filler and chitosan as matrix. The effects of α‐ZrP on the structure and properties of the nanocomposites were investigated. X‐ray diffraction patterns showed that α‐ZrP crystals were intercalated by n‐butylamine. The results from scanning electron microscopy and transmission electron microscopy indicated that α‐ZrP could be uniformly dispersed in the chitosan matrix when α‐ZrP loading in the composites was less than 2 wt%. A strong interaction between α‐ZrP and chitosan formed during the film‐forming process. Tensile testing showed that the tensile strength and elongation at break of nanocomposite films achieved maximum values of 61.6 MPa and 58.1%, respectively, when α‐ZrP loading was 2 wt%. The parameter B calculated from tensile yield stress according to the Pukanszky model was used to estimate the interfacial interaction between the chitosan matrix and α‐ZrP. Films with a loading of 2 wt% α‐ZrP had the highest B value (3.2), indicating the strongest interfacial interaction. The moisture uptake of the nanocomposites was reduced with addition of α‐ZrP. It can be concluded that α‐ZrP as nano‐filler in a chitosan matrix can enhance the mechanical properties of nanocomposites due to the strong interactions between α‐ZrP and chitosan. Copyright © 2010 Society of Chemical Industry     

Water and water vapor sorption studies in polypropylene–zeolite composites

Water and water vapor sorption to porous polypropylene–zeolite composites prepared by hot pressing have been studied as a function of zeolite loading. This work presents the first report on the effect of the zeolite as a filler on the water‐sorption properties of PP composites. Water swelling experiments were conducted at 25°C using pure PP and PP–zeolite films samples having different zeolite loadings (6–40 wt %). Because PP is a hydrophobic polymer, it does not sorp any water, but the composites having 10, 20, 30, and 40% zeolites have sorbed 0.63, 1.00, 1.72 and 3.74% water, respectively. The zeolite itself at the same conditions sorbed 24.5% water. As the filler loading in the composites increased, equilibrium uptake values increased also. On the other hand, water vapor sorption and kinetics has been studied using a Cahn 2000 gravimetric sorption system. Within in the range of 0.35–0.95% water vapor was adsorbed by the composites containing 10–40 wt % zeolites. Experimental effective water vapor diffusivities of the composite films was about one order of magnitude higher (10‐fold) than the experimental water diffusion coefficient in composites. The transport of water in composites was slower than that in the liquid water due to the longer diffusion pathway and adsorption on the surface of the composites. Although the liquid water may fill all the voids in the composite, water vapor is adsorbed on the surface of the zeolite only. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3069–3075, 2003     

High‐performance nanocomposites based on arcylonitrile‐butadiene rubber with fillers of different particle size: Mechanical and morphological studies

Acrylonitrile‐butadiene rubber (NBR) nanocomposites with layered silicate (LS), calcium phosphate (CP), and titanium dioxide (TO) of different particle size were prepared in an open two‐roll mixing mill at different filler loading in presence of sulphur as vulcanizing agent. The layered silicate (LS) filled system showed outstanding enhancement in mechanical properties in comparison with nanocalcium phosphate (CP) and titanium dioxide (TO). The variations in properties can be attributed to the extent of intercalation/exfoliation, which was highly influenced by the filler size. The layered silicate filled system at 20 phr showed nearly 349% increase in tensile strength compared to pure NBR whereas an increase of 110% and 84% were shown by CP and TO filled systems respectively. The modulus enhancements were in the order of 200%, 63% and 22%, respectively compared to the unfilled system. The increase in tear resistance was in the order of 230%, 115%, and 41% respectively for the filled systems in comparison with unfilled NBR. The significant enhancements in mechanical properties were supported by the morphological analysis. POLYM. COMPOS., 31:1515–1524, 2010. © 2009 Society of Plastics Engineers     

Poly(ethylene-co-vinyl acetate)/calcium phosphate nanocomposites: contact angle, diffusion and gas permeability studies

Poly(ethylene-co-vinyl acetate) (EVA) based nanocomposites were prepared by melt mixing in an internal mixer with nanoparticles of calcium phosphate. Contact angle measurements of the composites with water and methylene iodide were measured. Parameters such as total solid surface free energy, work of adhesion, interfacial free energy and spreading coefficient were calculated. The interaction parameter between the polymer and the liquid has been calculated using Girifalco-Good’s equation. Water diffusion studies of the composites were done at two different temperatures, 27 °C and 50 °C to know the solvent uptake behaviour. Water diffusion showed remarkable reduction with respect to the filler content. Gas permeability studies with oxygen and nitrogen also showed improvement in barrier properties for the composites.     

Effect of clay exfoliation and organic modification on morphological,dynamic mechanical,and thermal behavior of melt‐compounded polyamide‐6 nanocomposites

Polyamide‐6/clay nanocomposites were prepared employing melt bending or compounding technique followed by injection molding using different organically modified clays. X‐ray diffraction and transmission electron microscopy were used to determine the molecular dispersion of the modified clays within the matrix polymer. Mechanical tests revealed an increase in tensile and flexural properties of the matrix polymer with the increase in clay loading from 0 to 5%. C30B/polyamide‐6 nanocomposites exhibited optimum mechanical performance at 5% clay loading. Storage modulus of polyamide‐6 also increased in the nanocomposites, indicating an increase in the stiffness of the matrix polymer with the addition of nanoclays. Furthermore, water absorption studies confirmed comparatively lesser tendency of water uptake in these nanocomposites. HDT of the virgin matrix increased substantially with the addition of organically modified clays. DSC measurements revealed both γ and α transitions in the matrix polymer as well as in the nanocomposites. The crystallization temperature (T_c) exhibited an increase in case of C30B/polyamide‐6 nanocomposites. Thermal stability of virgin polyamide‐6 and the nanocomposites has been investigated employing thermogravimetric analysis. POLYM. COMPOS., 28:153–162, 2007. © 2007 Society of Plastics Engineers     

Structural,thermal, and gas transport properties of HDPE/LLDPE blend‐based nanocomposites using a mixture of HDPE‐g‐MA and LLDPE‐g‐MA as compatibilizer

Nanocomposites based on high density polyethylene (HDPE)/linear low density polyethylene (LLDPE) blend were prepared by melt compounding in a twin‐screw extruder using organoclay (montmorillonite) as nano‐filler and a 50/50 wt% mixture of maleic anhydride functionalized high density polyethylene (HDPE‐g‐MA) and linear low density polyethylene (LLDPE‐g‐MA) as the compatibilizing system. The addition of a maleated polyethylene‐based compatibilizing system was required to improve the organoclay dispersion in the HDPE/LLDPE blend‐based nanocomposite. In this work, the relationships between thermal properties, gas transport properties, and morphology were correlated. The compatibilized nanocomposite exhibited an intercalated morphology with a small number of individual platelets dispersed in the HDPE/LLDPE matrix, leading to an significant decrease in the oxygen permeation coefficient of the nanocomposites. A decrease in the carbon dioxide permeability and oxygen permeability with increase of nanoclay was observed for the compatibilized nanocomposites. The carbon dioxide permeability of the compatibilized nanocomposites was lower than the carbon dioxide permeability of the uncompatibilized nanocomposites even with the low intrinsic barrier properties of the compatibilizer. These effects were attributed to a good dispersion of the inorganic filler, good wettability of the filler by the polymer matrix, and strong interactions at the interface that increased the tortuous path for diffusion. Theoretical permeability models were used to estimate the final aspect ratio of nanoclay in the nanocomposite and showed good agreement with the aspect ratio obtained directly from TEM images. POLYM. ENG. SCI., 56:765–775, 2016. © 2016 Society of Plastics Engineers     

Mechanical,thermal, and transport properties of nitrile rubber–nanocalcium carbonate composites

The article describes the properties of acrylonitrile butadiene copolymer (NBR)–nanocalcium carbonate (NCC) nanocomposites prepared by a two‐step method. The amount of NCC was varied from 2 phr to 10 phr. Cure characteristics, mechanical properties, dynamic mechanical properties, thermal behavior, and transport properties of NBR–NCC composites were evaluated. For preparing NBR nanocomposites, a master batch of NBR and NCC was initially made using internal mixer. Neat NBR and the NBR–NCC masterbatch was compounded with other compounding ingredients on a two roll mill. NCC activated cure reaction upto 5 phr. The tensile strength increased with the nanofiller content, whereas NBR–NCC containing 7.5 phr exhibited the highest modulus. The storage modulus (E′) increased up to 5 phr NCC loading; the reinforcing effect of NCC was seen in the increase of modulus which was more significant at temperatures above T_g. The effect of nanofiller content and temperature on transport properties was evaluated. The solvent uptake decreased with NCC content. The mechanism of diffusion of solvent through the nanocomposites was found to be Fickian. Transport parameters like diffusion, sorption, and permeation constants were determined and found to decrease with nanofiller content, the minimum value being at 7.5 phr. Thermodynamic constants such as enthalpy and activation energy were also evaluated. The dependence of various properties on NCC was supported by morphological analysis using transmission electron microscopy. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Preparation and properties of nano‐CaCO3/acrylonitrile‐butadiene‐styrene composites

CaCO₃/acrylonitrile‐butadiene‐styrene (ABS) and CaCO₃/ethylene‐vinyl acetate copolymer (EVA)/ABS nanocomposites were prepared by melting‐blend with a single‐screw extruder. Mechanical properties of the nanocomposites and the dispersion state of CaCO₃ particles in ABS matrix were investigated. The results showed that in CaCO₃/EVA/ABS nanocomposites, CaCO₃ nanoparticles could increase flexural modulus of the composites and maintain or increase their impact strength for a certain nano‐CaCO₃ loading range. The tensile strength of the nanocomposites, however, was appreciably decreased by adding CaCO₃ nanoparticles. The microstructure of neat ABS, CaCO₃/ABS nanocomposites, and CaCO₃/EVA/ABS nanocomposites was observed by scanning electron microscopy. It can be found that CaCO₃ nanoparticles were well‐dispersed in ABS matrix at nanoscale. The morphology of the fracture surfaces of the nanocomposites revealed that when CaCO₃/EVA/ABS nanocomposites were exposed to external force, nano‐CaCO₃ particles initiated and terminated crazing (silver streak), which can absorb more impact energy than neat ABS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Multiwalled carbon nanotube/montmorillonite hybrid filled ethylene‐co‐vinyl acetate nanocomposites with enhanced mechanical properties,thermal stability,and dielectric response

Homogeneous multiwalled carbon nanotube/montmorillonite hybrid filler (HMM) dispersion was prepared by co‐ultrasonication and was subsequently used to prepare ethylene‐co‐vinyl acetate (EVA) nanocomposites by solution blending method. XRD and TEM analysis of HMM confirm significant interaction between the montmorillonite (MMT) layers and multiwalled carbon nanotubes (MWCNT) in line with previous reports. Analysis of the nanocomposites shows the constituent fillers to be homogeneously dispersed in EVA matrix. Mechanical properties of neat EVA are remarkably improved with HMM content up to 3 wt% followed by reversion. Maximum improvement observed in tensile strength, elongation at break, and toughness are 424%, 109%, and 1122%, respectively. Results show maximum thermal stability at 4 wt% and best dielectric response at 1 wt% HMM content. Exceptional mechanical and dielectric properties of EVA nanocomposites attained may be attributed to homogeneous dispersion of fillers and improved polymer–filler interaction. Comparison shows excellent synergy between MWCNT and MMT towards mechanical reinforcement of EVA. POLYM. ENG. SCI., 58:1155–1165, 2018. © 2017 Society of Plastics Engineers     

Exertion of Inhibiting Effect by Aluminosilicate Layers on Swelling of Solution Blended EVA/Clay Nanocomposite

Summary: Ethylene vinyl acetate (EVA) copolymer/dodecyl ammonium ion intercalated montmorillonite (12Me‐MMT) nanocomposites were swelled in xylene under atmospheric condition. Swelling index of these nanocomposites decreased with filler loading indicating that the solvent uptake of these nanocomposites was inversely related to the filler contents. The volume fractions of nanocomposites showed an increasing trend with filler concentration because of unswelling effect exerted by aluminosilicate layers. The cross‐link density was determined using the Flory‐Rehner equation and it was observed that the cross‐link density of these nanocomposites also showed an increasing trend with increasing filler loading. Free energy change (ΔG_mix) and the change in entropy (ΔS_mix) on swelling of EVA/12Me‐MMT nanocomposites in xylene were calculated and these values reaffirmed that the interaction between polymer chains and silicate layers was very strong which induced remarkable inhibiting ability on EVA matrix when swelled in xylene.

TEM photograph of EVA/12Me‐MMT nanocomposite containing 8 wt.‐% 12Me‐MMT.     

Interaction of silica and carbon black fillers with natural rubber/poly(ethylene‐co‐vinyl acetate) matrix by swelling studies

The interaction of a black filler and a white filler, which are extensively used in the rubber industry, with natural rubber/poly (ethylene‐co‐vinyl acetate) (NR/EVA) blends vulcanized by DCP has been examined by equilibrium swelling technique. Blends loaded with intermediate super abrasion furnace black (ISAF) and those with silica (SiO₂), of same loading, have been used. The silica incorporated blends sorbed a higher amount of aromatic solvents, compared with the ISAF filled blends, when NR was the continuous phase. However, the silica filled systems showed lower sorption characteristics when EVA became the continuous phase. This has been explained in terms of the differences in the interaction between the filler particles and the blend components. The swelling coefficient, diffusion coefficient, and molar mass between crosslinks have been computed to complement the experimental observations. POLYM. COMPOS., 28:705–712, 2007. © 2007 Society of Plastics Engineers     

Preparation and characterization of monovalent ion‐selective poly(vinyl chloride)‐blend‐poly(styrene‐co‐butadiene) heterogeneous anion‐exchange membranes

New types of composite anion‐exchange membranes were prepared by blending of suspension‐produced poly(vinyl chloride) (S‐PVC) and poly(styrene‐co‐butadiene), otherwise known as styrene–butadiene rubber (SBR), as binder, along with anion‐exchange resin powder to provide functional groups and activated carbon as inorganic filler additive. Also, an ultrasonic method was used to obtain better homogeneity. In solutions with mono‐ and divalent anions, the effect of activated carbon and sonication on the morphology, electrochemical properties and selectivity of these membranes was elucidated. For all solutions, ion‐exchange capacity, membrane potential, permselectivity, transport number, ionic permeability, flux and current efficiency of the prepared membranes initially increased on increasing the activated carbon concentration to 2 wt% in the casting solution and then began to decrease. Moreover, the electrical resistance and energy consumption of the membranes initially decreased on increasing the activated carbon loading to 2 wt% and then increased. S‐PVC‐blend‐SBR membranes with additive showed a decrease in water content and a slight decrease in oxidative stability. Also, these membranes showed good monovalent ion selectivity. Structural images of the prepared membranes obtained using scanning optical microscopy showed that sonication increased polymer‐particle interactions and promoted the compatibility of particles with binder. Copyright © 2010 Society of Chemical Industry     

Fabrication and characterization of HCl‐treated clinoptilolite filled ethylene vinyl acetate composite films

As received and HCl treated Clinoptilolite (C)‐ethylene vinyl acetate (EVA) composites were prepared via the melt‐mixing technique, and extruded through a single‐screw extruder to obtain composite strips with an average thickness of 0.5 mm. The films were then characterized for their morphological, structural, thermal, and mechanical properties. Optical micrographs show that at higher C loading, the particles form large agglomerates, resulting in the formation of voids on the surface of the films. With increasing zeolite loading, the films become brittle, resulting in reduced Young's modulus. Acid treatment of the C tends to affect the crystal structure of the zeolite, resulting in poor tensile properties of the HCl‐treated zeolite‐filled EVA films. Addition of the zeolite also increased the crystallinity of the structure, acting as a nucleating agent in the EVA crystallization. Modeling of the tensile yield data with Pukanszky model indicate that there is poor interfacial adhesion between the polymer matrix and the filler particles. Thermal characterization studies showed that addition of the zeolites retarded the onset degradation temperature of EVA. However, degradation temperatures including T_max and the final decomposed temperature were increased, suggesting improved thermal stability due to reduced inter‐chain mobility in the composite materials as a result of increased zeolite loading. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Natural rubber/poly(ethylene‐co‐vinyl acetate)‐blend‐based nanocomposites

Natural rubber (NR)/poly(ethylene‐co‐vinyl acetate) (EVA) blend–clay nanocomposites were prepared and characterized. The blend nanocomposites were prepared through the melt mixing of NR/EVA in a ratio of 40/60 with various amounts of organoclay with an internal mixer followed by compression molding. X‐ray diffraction patterns revealed that the nanocomposites formed were intercalated. The formation of the intercalated nanocomposites was also indicated by transmission electron microscopy. Scanning electron microscopy, used to study the fractured surface morphology, showed that the distribution of the organoclay in the polymer matrix was homogeneous. The tensile modulus of the nanocomposites increased with an increase in the organoclay content. However, an increase in the organoclay content up to 5 phr did not affect the tensile strength, but the organoclay reduced this property when it was increased further. This study also indicated that a low silicate content dispersed in the blend matrix was capable of increasing the storage modulus of the material. The addition of the organoclay also increased the decomposition temperature of the NR/EVA blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 353–362, 2006     

Use of pyrolyzed oil shale as filler in poly(ethylene‐co‐vinyl acetate) with different vinyl acetate contents

Pyrolyzed oil shale (POS) obtained from the pyrolysis of bituminous rock was used as filler in poly(ethylene‐co‐vinyl acetate) (EVA). The effects of the VA content of EVA and the particle size of POS on the mechanical properties were investigated. The composites were prepared in a rotor mixer at 180°C with a concentration of POS of up to 30 wt %. The stress–strain plots of the compression‐molded composites are similar to the EVA (18% VA content) behavior for low concentrations (1–5 wt %) of POS with a particle size lower than 270 mesh. It was observed that decreasing the POS particle size and increasing the VA content of EVA produced better compatibility between the polymer and filler. The mechanical properties, differential scanning calorimetry, and dynamic mechanical analysis also demonstrated the compatibility between EVA and POS under the increase of the VA content in the EVA. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1544–1555, 2002; DOI 10.1002/app.10494     

Effects of different preparation methods on the properties of poly[ethylene‐co‐(vinyl acetate)]/(Standard Malaysian natural rubber)/organoclay nanocomposites

Poly[ethylene‐co‐(vinyl acetate)] (EVA)/(Standard Malaysian natural rubber) (SMR L)/organoclay nanocomposites were prepared by using melt intercalation and solution blending methods. In both preparation methods, the EVA: (SMR L) ratio was prefixed at 50:50, while the organoclay loading was varied from 0 to 10 phr. The effects of two different processing routes and organoclay loading on the morphology, tensile, properties thermal properties, and flammability of the nanocomposites were studied. X‐ray diffraction results and transmission electron microscopy images proved that solution blending promotes better dispersion of organoclay than melt intercalation. Thus, the nanocomposites prepared by the solution‐blending method exhibited higher values of tensile strength, stress at 100% elongation (M100), and thermal stability. The M100 value and thermal stability improved proportionally with the increase of organoclay content, owing to the demobilizing effect and the barrier properties of the organoclay. The optimum tensile strength value was achieved at a 2‐phr organoclay loading. Further increases in loading decreased the strength of the nanocomposites. Tensile fracture surfaces of the nanocomposites prepared by both methods showed different fracture behavior, as evidenced by scanning electron microscopy images. Flammability decreased when the organoclay loading increased for the nanocomposites prepared by both methods. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers     

Synthesis of poly(arylene disulfide)–vermiculite nanocomposites via in situ ring‐opening polymerization of macrocyclic oligomers

Exfoliated poly(4, 4′‐oxybis(benzene)disulfide)/vermiculite (POBDS/VMT) nanocomposites were successfully synthesized via in situ melt intercalation of cyclo(4, 4′‐oxybis(benzene)disulfide) oligomers (COBDS) into octadecylammonium‐exchanged VMT (organo‐VMT). The POBDS/VMT nanocomposites were melt fabricated in a two‐step process. First, the COBDS/VMT nanocomposite precursor was fabricated by melt delaminating organo‐VMT with COBDS at a temperature slightly higher than its melting point. Subsequently, exfoliated POBDS‐VMT nanocomposites can be prepared in situ via instant melt ring‐opening polymerization of the COBDS‐VMT nanocomposite precursor. The nanoscale dispersion of VMT layers within POBDS polymer was confirmed by X‐ray diffraction, scanning electron microscopy and transmission electron microscopy. High molecular weight POBDS polymer was formed in a few minutes at the same time as the nanocomposite formation. The results of dynamic mechanical analysis showed that the storage modulus and glass transition temperature of the nanocomposites are much higher than those of the POBDS matrix, even with a very small amount of VMT addition. This methodology provides a potential approach to synthesize high‐performance polymer/clay nanocomposites. Copyright © 2004 Society of Chemical Industry