A simple and environmentally friendly method for surface modification of ZrO2 nanoparticles by biosafe citric acid as well as ascorbic acid (vitamin C) and its application for the preparation of poly(vinyl chloride) nanocomposite films

In this investigation, poly(vinyl chloride) (PVC) as one of the most important thermoplastic polymer was combined with different concentrations (4, 8, and 12 wt%) of ZrO₂ nanoparticles (NPs) with the purpose of preparing novel nanocomposites (NCs). To prevent aggregation and obtain homogeneous dispersion of the NPs in the polymer matrix, surface modification of ZrO₂ was performed by biosafe, biodegradable as well as biocompatible modifiers such as citric acid and ascorbic acid (vitamin C) due to their ability to form chelates with metal oxides. The effect of modified ZrO₂ on the properties of the PVC was studied by different techniques. The field emission scanning electron microscopy and transmission electron microscopy results indicated that the modified NPs were dispersed homogeneously in the polymer matrix. UV–Vis spectroscopy was used to study optical behaviors of the obtained NCs. Thermogravimetric analysis indicated that the thermal stability of the polymer was enhanced after incorporation with NPs. Finally, mechanical test was revealed that the NC films were more flexible when compared with the neat polymer. POLYM. COMPOS., 38:1756–1765, 2017. © 2015 Society of Plastics Engineers     

A nonradiative energy transfer fluorescence spectroscopy study of poly(vinyl chloride)/poly(methyl methacrylate) blends

The miscibility of poly(vinyl chloride)/atactic poly(methyl methacrylate (PVC/a-PMMA) blends was investigated by nonradiative energy transfer fluorescence spectroscopy using naphthalene-labeled PVC (PVC-N) with anthracene-labeled PMMA (PMMA-A), or anthracene-labeled PVC (PVC-A) with carbazole-labeled PMMA (PMMA-C). The two sets of results indicate an increase in energy transfer efficiency, corresponding to an increase in blend miscibility, as the PVC concentration increases and, more importantly, demonstrate that the same information about blend miscibility can be obtained using different donor-acceptor chromophore pairs and by changing the polymer to which the donor or the acceptor is attached. The effect of the tacticity of PMMA on its miscibility with PVC was also investigated using PMMA-C and PVC-A labeled polymers. The results confirm that PVC/a-PMMA blends are more miscible than PVC/i-PMMA blends over a large range of compositions.     

Dynamic mechanical behavior of poly(vinyl chloride)/poly(methyl methacrylate) polymer blend

A poly(vinyl chloride) (PVC)/poly(methyl methacrylate) (PMMA) (80/20 w/w) polymer blend was studied by mechanical spectroscopy. Two relaxations can be distinguished: in the glassy state, a very large secondary relaxation in the range of 100 K to 325 K which results from the combination of secondary relaxations of PVC and PMMA; and only one main relaxation at 364 K associated to the glass rubber transition. The relaxation spectrum in the range of the β relaxation has been described by a relaxation time distribution function based upon a Gaussian function and a series-parallel model. The α relaxation was studied by means of a theoretical approach for the nonelastic deformation of polymers. We found that the miscibility of this blend appears to be a function of the observation scale: the PVC/PMMA blend is heterogeneous at the scale of molecular movements involved for the β relaxation process but homogeneous at the scale of the chain segments responsible for the α relaxation dynamics. © 1996 John Wiley & Sons, Inc.     

Effect of organoclay on the properties of maleic‐anhydride grafted polypropylene and poly(methyl methacrylate) blend

Poly(methyl methacrylate)/polypropylene (PMMA/PP) and PMMA/maleic‐anhydride grafted PP (MAPP) blends and their blend nanocomposites containing 2 wt% organoclay (Cloisite 15A, denoted C15A), prepared by a melt mixer were studied. Both X‐ray diffraction (XRD) and transmission electron microscopy (TEM) revealed exfoliated polymer blend nanocomposites. Scanning electron microscopy (SEM) studies indicated a droplet dispersion morphology for all the blends while addition of C15A into PMMA/MAPP blend resulted to a co‐continuous morphology. In fact, rheological data and thermal properties indicated that the PMMA/MAPP/C15A nanocomposite showed a better homogeneous dispersion of silicate layers than PMMA/PP/C15A nanocomposite. A Cole–Cole plot and relaxation modulus indicated a solid‐like character for PMMA/MAPP and PMMA/MAPP/C15A, while a liquid‐like behavior was noticed for PMMA/PP and PMMA/PP/C15A. The effect of an organoclay on the dynamic mechanical properties of samples was investigated using dynamic mechanical analysis (DMA) which showed a significant enhancement on the storage modulus of the PMMA/MAPP/C15A as compared to PMMA/PP/C15A . POLYM. COMPOS., 38:431–440, 2017. © 2015 Society of Plastics Engineers     

Preparation and Electron Beam Irradiation of PVC/ENR/CNTs Nanocomposites

Poly (vinyl chloride), PVC/epoxidized natural rubber blend, ENR/carbon nanotubes, CNTs nanocomposites were prepared using melt intercalation and solution blending methods. In both preparation methods PVC: ENR: CNTs ratios were fixed at 50:50:2, while the 50/50 PVC/ENR blend without the addition of CNTs was used as control. The PVC/ENR/CNTs nanocomposites were exposed to electron beam (EB) irradiation at doses ranging from 0–200 kGy. The effects of two different preparation methods on the tensile properties, gel fraction and morphology of the PVC/ENR/CNTs nanocomposites were studied. Prior to EB irradiation, the addition of 2 phr of CNTs caused a drop in the tensile strength (Ts) of the 50/50 PVC/ENR blend, implying poor distribution of CNTs in the PVC/ENR blend matrix. However upon EB irradiation, the nanocomposites prepared by the melt blending method exhibited higher values of Ts as compared to the neat PVC/ENR blend due to occurrence of radiation-induced cross-linking in the PVC/ENR blend matrix. Transmission electron microscopy (TEM) images proved that a better dispersion of CNTs in PVC/ENR blend matrix can be achieved by melt intercalation compared to solution blending and the dispersion of CNTs was improved by irradiation. Scanning electron microscopy (SEM) results showed a distinct failure surface with formation of rough structure for the irradiated nanocomposites, which explains the higher values of tensile properties compared to the non-irradiated nanocomposites.     

Influence of molecular weight of poly (methyl methacrylate) on its miscibility with poly (vinyl chloride) in the solution

In this work, the molecular weight effect on miscibility between poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA) in cyclohexanone(CH) solutions at 30 °C was examined by the viscometric method. Three samples of PMMA were prepared by emulsion polymerization, which molecular weights were changed by tert-dodecyl-mercaptan (TDDM) content. The parameter Δb is used to predict polymer-polymer miscibility of PVC/PMMA/cyclohexanone blend. Δb values indicated that the highest molecular weight of PMMA is immiscible with PVC resin. The molecular weight of PMMA decrease with the increase of the contention of TDDM, and the contribution of miscibility PVC/PMMA blend in CH is better.     

Crystallization behavior and hydrophilicity of poly(vinylidene fluoride)/poly(methyl methacrylate)/poly(vinyl pyrrolidone) ternary blends

Ternary blends composed of matrix polymer poly(vinylidene fluoride) (PVDF) with different proportions of poly(methyl methacrylate) (PMMA)/poly(vinyl pyrrolidone) (PVP) blends were prepared by melt mixing. The miscibility, crystallization behavior, mechanical properties and hydrophilicity of the ternary blends have been investigated. The high compatibility of PVDF/PMMA/PVP ternary blends is induced by strong interactions between the carbonyl groups of the PMMA/PVP blend and the CF₂ or CH₂ group of PVDF. According to the Fourier transform infrared and wide‐angle X‐ray difffraction analyses, the introduction of PMMA does not change the crystalline state (i.e. α phase) of PVDF. By contrast, the addition of PVP in the blends favors the transformation of the crystalline state of PVDF from non‐polar α to polar β phase. Moreover, the crystallinity of the PVDF/PMMA/PVP ternary blends also decreases compared with neat PVDF. Through mechanical analysis, the elongation at break of the blends significantly increases to more than six times that of neat PVDF. This confirms that the addition of the PMMA/PVP blend enhances the toughness of PVDF. Besides, the hydrophilicity of PVDF is remarkably improved by blending with PMMA/PVP; in particular when the content of PVP reaches 30 wt%, the water contact angle displays its lowest value which decreased from 91.4° to 51.0°. Copyright © 2011 Society of Chemical Industry     

Property improvement of plasticized poly(vinyl chloride) by nano‐TiO2 and poly(methyl methacrylate)–encapsulated nano‐TiO2

To improve the physical properties of plasticized poly(vinyl chloride) (p‐PVC), the p‐PVC nanocomposites filled with four loading levels (3, 5, 7, and 9 parts per hundred of PVC resin) of either nanosized titanium dioxide (nTiO₂) or poly(methyl methacrylate)–encapsulated nTiO₂ (PMMA‐nTiO₂) were prepared by melt mixing on a two‐roll mill, followed by compression molding. The PMMA‐nTiO₂ used in this study was synthesized via in situ differential microemulsion polymerization. The resulting PMMA‐nTiO₂ exhibited core‐shell morphology (nTiO₂ core and PMMA shell) with an average diameter of 42.6 nm. The effects of nTiO₂ and PMMA‐nTiO₂ on the tensile properties, hardness, morphology, and thermal stability of the as‐prepared p‐PVC nanocomposites were then investigated and compared. The inclusion of either nTiO₂ or PMMA‐nTiO₂ nanoparticles increased the tensile strength, Young's modulus, hardness, and thermal stability of the nanocomposites in a dose‐dependent manner and reduced the elongation at break. However, the elongation at break was still higher than that for the neat p‐PVC. Moreover, the PMMA‐nTiO₂ nanocomposites had a higher enhancement of the tensile strength, Young's modulus, hardness, and thermal stability than the nTiO₂ nanocomposites at a similar loading level. Hence, the PMMA grafted on the nTiO₂ surface played an important role in toughening and increasing the thermal stability of the nanocomposites owing to the improved miscibility and interfacial adhesion between the encapsulated nanofiller and PVC matrix. J. VINYL ADDIT. TECHNOL., 22:433–440, 2016. © 2015 Society of Plastics Engineers     

Effect of organoclay in an immiscible poly(ethylene terephtalate) waste/poly(methyl methacrylate) blend

Blends of organically modified montmorillonite (OMMT) with poly(ethylene terephtalate) (PET) waste and poly(methyl methacrylate) (PMMA) were prepared by melt mixing. The morphology of PET/PMMA nanocomposites with different OMMT contents was characterized by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The nonisothermal crystallization temperatures of nanocomposites were also examined by DSC. TEM observations and XRD patterns revealed that silicate layers were intercalated and well dispersed in the blend. Nanocomposites displayed better mechanical properties when compared with the unfilled blend. DMA analyses also showed efficient mixing of the two immiscible polymers and changes in glass transition temperature with the presence of OMMT. DSC analysis showed an enhancement in crystallization rate of nanocomposites and a decrease in cristallinity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Investigation of the crystalline structure of PVDF in PVDF/PMMA/graphene polymer blend nanocomposites

In this work, we report the preparation of poly(vinylidene fluoride)/poly methylmethacrylate (PVDF/PMMA)/graphene polymer blend nanocomposites via synthesis of PMMA/graphene as a masterbatch through in situ polymerization. The PMMA/graphene masterbatch compounded with PVDF by solution mixing in different ratios. The compounding was followed by solution casting to form polymer blend nanocomposites. Solution cast films were subjected to thermal treatments at three different temperatures. The crystalline structure of thermally treated samples was studied with X‐ray diffraction spectroscopy and Differential Scanning Calorimetric (DSC) analysis. Results indicated PMMA chains persuade the β crystalline form in PVDF but cannot stabilize them in elevated temperature; however, graphene sheets due to restricting effect on TT conformation chains are able to stabilize them. DSC data revealed the graphene sheets can increase the crystallinity of PVDF and also act as nucleating agents. Transmission Electron Microscopy demonstrated coexistence of the different stacking orders of graphene sheets in both masterbatch and polymer blend nanocomposite. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

Rheology and morphology study of immiscible linear low‐density polyethylene/poly(lactic acid) blends filled with nanosilica particles

The objectives of this study are to investigate the effect of silica nanoparticles on the morphology and rheological behavior of immiscible linear low‐density polyethylene/poly(lactic acid) (LLDPE/PLA) blends. Melt blending method is applied to prepare the blends and their nanocomposites. Scanning electron microscope and parallel plate rheometer were used to investigate morphology and rheological behavior of the blend nanocomposites. Scanning electron microscope results demonstrated a significant change in morphology behavior by incorporation of silica nanoparticles. A significant reduction in the PLA droplet for LLDPE/PLA (75/25) with 8 wt % silica was observed. The rheological studies illustrated that for all samples storage modulus and complex viscosity of blend nanocomposites are higher than neat blends. Finally, melt rigidity of blend nanocomposites was estimated by measurement of rheological properties using a rotational rheometer through small amplitude oscillatory shear experiments. As a result, through the shear data, a high value quantity as a criteria for melt rigidity is obtained for the LLDPE/PLA (75/25) with 8 wt % silica in comparing to the other samples. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45526.     

New method of determining miscibility in binary polymer blends through hydrodynamic interaction: The free volume approach

A new method has been developed to determine the probability of miscibility in binary polymer blends through hydrodynamic interaction. This is achieved by the measurement of the free volume content in blends of carefully selected systems—styrene acrylonitrile (SAN)/poly(methyl methacrylate) (PMMA), PMMA/poly(vinyl chloride) (PVC), and PVC/polystyrene (PS)—with positron annihilation lifetime spectroscopy. The free volume content can predict the miscible/immiscible nature of the blends but provides no information on the extent of miscibility for different compositions of the blends. We have generalized a model used to understand the viscometric behavior of polymer/solvent systems to polymer/polymer systems through the free volume approach. This model provides two important parameters: a geometric factor (γ) and a hydrodynamic interaction parameter (α). γ depends on the molecular architecture, whereas α accounts for the excess friction at the interface between the constituents of the blend, and we propose that α can serve as a precursor to miscibility in a system and indicate which composition produces a high probability of miscibility. The efficacy of this proposition has been checked with measured free volume data for the three blend systems. The SAN/PMMA system produces a maximum α value of ?209 at 20% PMMA; PVC/PMMA produces a maximum α value of ?57 at 10% PMMA. Interestingly, for the PS/PVC system, α is close to zero throughout the entire concentration range. Therefore, we infer that α is perhaps an appropriate parameter for determining the composition‐dependent probability of miscibility in binary blend systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and properties of poly(methyl methacrylate)/carbon nanotube composites covalently integrated through in situ radical polymerization

Poly(methyl methacrylate) (PMMA)/single‐walled carbon nanotube (SWNT) composites were synthesized by the grafting of PMMA onto the sidewalls of SWNTs via in situ radical polymerization. The free‐radical initiators were covalently attached to the SWNTs by a well‐known esterification method and confirmed by means of thermogravimetric analysis and Fourier transform infrared spectroscopy. Scanning electron microscopy and transmission electron microscopy were used to image the PMMA–SWNT composites; these images showed the presence of polymer layers on the surfaces of debundled, individual nanotubes. The PMMA–SWNT composites exhibited better solubility in chloroform than the solution‐blended composite materials. On the other hand, compared to the neat PMMA, the PMMA–SWNT nanocomposites displayed a glass‐transition temperature up to 6.0°C higher and a maximum thermal decomposition temperature up to 56.6°C higher. The unique properties of the nanocomposites resulted from the strong interactions between the SWNTs and the PMMA chains. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Thermal degradation and flammability of nanocomposites composed of silica cross-linked to poly(methyl methacrylate)

The effect of polymer cross-linkages on thermal degradation of silica/poly (methyl methacrylate) (PMMA) nanocomposites is investigated using a single novel nanoparticle. Nanosilica surface treated with KH570, an organic surface treatment capable of free-radical polymerisation, was used to cross-link PMMA via an in situ method. Scanning electron microscopy was used to characterise nanosilica before use, while X-ray diffraction confirmed silica was well dispersed in PMMA. Thermogravimetric analysis (TGA) results showed that thermal degradation of silica cross-linked nanocomposites was significantly stabilised compared to PMMA, with a 30% reduction in the peak mass loss rate. Kinetic studies revealed the degradation of nanocomposites in this work abide by first-order kinetics, with an increase in the degradation activation energy of approximately 100?kJ?mol^?1. This is nearly double the improvement compared to conventional PMMA-silica nanocomposites in literature, showing dramatic enhancements to thermal stability. Analysis of high-temperature residuals from TGA tests suggest that cross-linked silica have increased char yields when compared with both PMMA and traditional silica nanocomposites. Cone Calorimetry results showed the materials in this work have reduced heat release rates compared to PMMA and traditional silica-PMMA nanocomposites.     

Effects of thermoplastic poly(ether-ester) elastomer and bentonite nanoclay on properties of poly(lactic acid)

This work presented the influence of thermoplastic poly(ether-ester) elastomer (TPEE) and bentonite (BTN) on improving the mechanical and thermal properties of poly(lactic acid) (PLA). PLA was initially melt mixed with TPEE at six different loadings (5–30 wt%) on a twin screw extruder and then injection molded. The mechanical tests revealed an increasing impact strength and elongation at break with increasing TPEE loading, but a diminishing Young's modulus and tensile strength with respect to pure PLA. The blend at 30 wt% TPEE provided the optimum improvement in toughness, exhibiting an increase in the impact strength and elongation at break by 3.21- and 10.62-fold over those of the pure PLA, respectively. Scanning electron microscopy analysis illustrated a ductile fractured surface of the blends with the small dispersed TPEE domains in PLA matrix, indicating their immiscibility. The 70/30 (wt/wt) PLA/TPEE blend was subsequently filled with three loadings of BTN (1, 3, and 5 parts by weight per hundred of blend resin [phr]), where the impact strength, Young's modulus, tensile strength and thermal stability of all the blends were improved, while the elongation at break was deteriorated. Among the three nanocomposites, that with 1 phr BTN formed exfoliated structure and so exhibited the highest impact strength, elongation at break, and tensile strength compared to the other intercalated nanocomposites. Moreover, the addition of BTN was found to increase the thermal stability of the neat PLA/TPEE blend due to the barrier properties and high thermal stability of BTN.     

The effect of the addition of poly(styrene‐co‐glycidyl methacrylate) copolymer on the properties of polylactide/poly(methyl methacrylate) blend

The effect of the addition of poly(styrene‐co‐glycidyl methacrylate) P(S‐co‐GMA) copolymer on the properties of melt blended polylactide/poly(methyl methacrylate) (PLA/PMMA) 80/20 (wt %) composition was studied. In the literature high ductility levels were achieved by melt blending PLA with different additives. However, the gained ductility was counter balanced with drastic drops in strength and modulus values. The novelty of this work was the preparation of PLA‐based blends with polylactide content higher than 75 wt % which showed an impact resistance value improvement of about 60% compared with the neat PLA and maintained similar tensile strength and modulus values as well as glass transition temperature to neat PLA. The addition of only 3 pph of copolymer to PLA/PMMA blend improved the impact resistance almost 100%. The chemical reaction between PLA/PMMA blend and P(S‐co‐GMA) copolymer were analyzed by FTIR, rotational rheometry, and GPC/SEC. Phase structure and morphology were studied by Differential Scanning Calorimetry and Scanning Electronic Microscopy. Tensile and impact properties as well as thermal stability were also studied. Results showed that as the amount of copolymer in the blend was increased then higher was average molecular weight and polydispersity index. After the addition of P(S‐co‐GMA) copolymer to the PLA/PMMA blend the impact resistance, elongation at break and thermal stability were improved while tensile strength and elastic modulus remained almost unaltered. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43935.     

Study of the solvent effect on miscibility between poly(vinyl chloride) and poly(methyl methacrylate) in the solution state – viscometric measurements

In this work, the solvent effect on the miscibility between poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA) in ternary polymer solutions was examined by the viscometric method. In these systems, we could understand that the used solvents, tetrahydrofuran (THF) or N,N‐dimethylformamide (DMF), mainly affect the interaction between PVC and PMMA, while prompting various miscible properties. In PVC/PMMA/THF solution, THF is a near θ‐solvent and a poor solvent for PVC and PMMA, respectively. The mixing of the tighter PMMA coils and more extended PVC coils in THF may cause the sea–island heterogeneous structure below the weight fraction of PMMA in the polymer mixture w_PMMA = 0.7, resulting in immiscible PVC/PMMA mixtures. At w_PMMA ≥ 0.7, the PVC/PMMA mixtures are relatively miscible, giving homogeneous polymer solutions. It means that the miscibility between PVC and PMMA depends on the composition of polymer mixture. However, due to the similar affinity of DMF to PVC and PMMA, PVC/PMMA/DMF solutions exhibit high miscibility between PVC and PMMA at about w_PMMA = 0.5. © 2000 Society of Chemical Industry     

Effect of blend composition and organoclay loading on the nanocomposite structure and properties of miscible poly(methyl methacrylate)/poly(styrene‐co‐acrylonitrile) blends

Organically‐modified montmorillonite clay nanocomposites of poly(styrene‐co‐acrylonitrile) (SAN), poly(methyl methacrylate) (PMMA) and SAN/PMMA miscible blend are investigated. Structure characteristics at the nanoscale and microscale and thermal and tensile properties are studied as a function of polymer blend composition and filler loading fraction. Blend miscibility and T_g are unaffected by up to 10% by wt. organoclay. Thermal degradation stability increases with SAN content and exhibits an optimum value of clay loading. Stiffness shows significant improvement. Tensile strength and elongation‐at‐break suffer as a result of nanocomposite formation. Modulus shows a maximum enhancement of 57% (5 ± 0.06 GPa at 10 wt% filler, 20/80 SAN/PMMA) and varies linearly with clay fraction for all compositions of matrix phase. Predictions of Halpin–Tsai composite model are in excellent agreement with the experimental behavior over full range of polymer blend composition. Fundamental aspects of a polymer blend–clay nanocomposite are clarified, such as lack of additional synergy between clay platelets and matrix, and tensile ductility reduction, compared with polymer–clay system. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

A study of poly vinyl chloride / poly(butylene adipate-co-terephthalate) blends

Polymer blends were prepared by melt blending technique using poly vinyl chloride (PVC) and poly(butylene adipate-co-terephthalate) (PBAT). Different ratios of the blends were studied to investigate their mechanical, thermal and morphological properties. The FTIR spectrum indicated a slight increase of frequencies at C = O peak from 1714 to 1718 cm^-1 indicating a chemical interaction between C = O of PBAT and α-hydrogen of PVC. The tensile properties of PVC/PBAT blends highest at weight ratio of 50/50. The dynamic mechanical analysis (DMA) result proves that PVC and PBAT formed a miscible system with one glass transition temperature (T_g). The incorporation of PBAT results in a gradual decrease of the viscosity (loss modulus) and an increase of elasticity (storage modulus). The thermal properties of blend show the decomposition temperature of PVC in the blend decrease with the addition of PBAT. Scanning electron micrograph shows good interfacial adhesion on the tensile fractured surface of PVC/PBAT blend, which played important roles in enhancing the mechanical properties (strength and modulus).     

Blending poly(methyl methacrylate) and poly(styrene‐co‐acrylonitrile) as composite polymer electrolyte

A blend of poly(methyl methacrylate) (PMMA) and poly(styrene‐co‐acrylonitrile) (PSAN) has been evaluated as a composite polymer electrolyte by means of differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, ac impedance measurements, and linear sweep voltammetry (LSV). The blends show an interaction with the Li⁺ ions when complexed with lithium perchlorate (LiClO₄), which results in an increase in the glass‐transition temperature (T_g) of the blends. The purpose of using PSAN as another component of the blend is to improve the poor mechanical properties of PMMA‐based plasticized electrolytes. The mechanical property is further improved by introducing fumed silica as inert filler, and hence the liquid electrolyte uptake and ionic conductivity of the composite systems are increased. Room‐temperature conductivity of the order of 10^?4 S/cm has been achieved for one of the composite electrolytes made from a 1/1 blend of PSAN and PMMA containing 120% liquid electrolyte [1M LiClO₄/propylene carbonate (PC)] and 10% fumed silica. These systems also showed good compatibility with Li electrodes and sufficient electrochemical stability for safe operation in Li batteries. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1319–1328, 2001