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Pierluigi Magagnini - One of the best experts on this subject based on the ideXlab platform.

  • thermal properties and microhardness of hdpe clay nanocomposites compatibilized by different functionalized polyethylenes
    Polymer Testing, 2009
    Co-Authors: L Minkova, Y Peneva, E Tashev, Sara Filippi, Mariano Pracella, Pierluigi Magagnini
    Abstract:

    Abstract The calorimetric characteristics, the flammability, the thermal stability and the microhardness of polyethylene high density/clay nanocomposites (HDPE/clay) have been studied by differential scanning calorimetry, thermogravimetry, determination of limiting oxygen index and microhardness tests. The nanocomposites have been compatibilized by ethylene–acrylic acid copolymer (EAA), acrylic acid grafted HDPE (HDAA) and maleic anhydride grafted HDPE (HDMA). The clay was montmorillonite Cloisite 15A. The influence of the presence and the type of the Compatibilizers on the properties of the nanocomposites has been evaluated. The results have shown that the thermal stability, the reduction of the flammability and the microhardness of HDPE/clay nanocomposites, compatibilized by HDAA and HDMA are higher than those for nanocomposite compatibilized by EAA. Moreover, the presence and the type of compatibilizer have negligible effect on the characteristics of the HDPE phase transitions. These results have been interpreted by the better clay dispersion and higher level of clay exfoliation in the presence of Compatibilizers HDAA and HDMA, than those in the presence of EAA compatibilizer.

  • reactive compatibilization of pa6 ldpe blends with an ethylene acrylic acid copolymer and a low molar mass bis oxazoline
    Polymer, 2003
    Co-Authors: Roberto Scaffaro, Sara Filippi, Francesco Paolo La Mantia, Loredana Canfora, Giovanni Polacco, Pierluigi Magagnini
    Abstract:

    Abstract A sample of polyamide-6 (PA) was blended with low density polyethylene (LDPE) in the 80/20 wt/wt ratio, either without and with 2 phr of an ethylene–acrylic acid copolymer (EAA), Which was known to behave as a compatibilizer precursor, and the effect of the addition of small amounts (0.2 or 0.35 phr) of a fourth component, 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO), was investigated. The reactions of PBO with EAA, PA and their blends were studied by recording as a function of time the torque applied to the blending apparatuses and by studying the solubility behavior of the products in formic acid. The PALDPE blends were prepared in a co-rotating twin screw extruder and were characterized by Molau tests, differential scanning calorimetry, scanning electron microscopy, rheology, and determination of the ultimate mechanical properties, including impact tests. The results indicate that the effectiveness of EAA as a compatibilizer precursor is considerably enhanced when PBO is added into the blends. It is thought that the reactions of PBO with the free carboxyl groups of EAA and with the amine or carboxyl end groups of PA run, at least in part, toward the formation of PA- g -EAA copolymers acting as the true Compatibilizers for these blends.

  • reactive compatibilization of pa6 ldpe blends with an ethylene acrylic acid copolymer and a low molar mass bis oxazoline
    Polymer, 2003
    Co-Authors: Roberto Scaffaro, Sara Filippi, Francesco Paolo La Mantia, Loredana Canfora, Giovanni Polacco, Pierluigi Magagnini
    Abstract:

    Abstract A sample of polyamide-6 (PA) was blended with low density polyethylene (LDPE) in the 80/20 wt/wt ratio, either without and with 2 phr of an ethylene–acrylic acid copolymer (EAA), Which was known to behave as a compatibilizer precursor, and the effect of the addition of small amounts (0.2 or 0.35 phr) of a fourth component, 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO), was investigated. The reactions of PBO with EAA, PA and their blends were studied by recording as a function of time the torque applied to the blending apparatuses and by studying the solubility behavior of the products in formic acid. The PALDPE blends were prepared in a co-rotating twin screw extruder and were characterized by Molau tests, differential scanning calorimetry, scanning electron microscopy, rheology, and determination of the ultimate mechanical properties, including impact tests. The results indicate that the effectiveness of EAA as a compatibilizer precursor is considerably enhanced when PBO is added into the blends. It is thought that the reactions of PBO with the free carboxyl groups of EAA and with the amine or carboxyl end groups of PA run, at least in part, toward the formation of PA- g -EAA copolymers acting as the true Compatibilizers for these blends.

Christopher W Macosko - One of the best experts on this subject based on the ideXlab platform.

  • intercalated linear low density polyethylene lldpe clay nanocomposites prepared with oxidized polyethylene as a new type compatibilizer structural mechanical and barrier properties
    European Polymer Journal, 2007
    Co-Authors: Ali Durmus, Maybelle Woo, Ahmet Kasgoz, Christopher W Macosko, Michael Tsapatsis
    Abstract:

    In this study, the use of low molecular weight oxidized polyethylenes (OxPE) with different molecular weight and acid number as a new type of compatibilizer in low density polyethylene (LLDPE)/org-clay nanocomposite preparation was examined. Nanocomposites having 5 phr (part per hundred) org-clay were prepared by melt processing. The effect of compatibilizer polarity and clay dispersion on the thermal, mechanical and barrier properties of the nanocomposites was investigated. It was observed that oxidized polyethylenes created a strong interfacial interaction between the clay layers and polymer phase based on the analysis of the linear viscoelastic behavior of the samples by small amplitude oscillatory rheometry. We showed that physical performance of the nanocomposites is not only affected by clay dispersion but also both melt viscosity and polarity of the oxidized polyethylene Compatibilizers. It was found that oxygen permeability values of the nanocomposite samples prepared with the oxidized polyethylenes were lower than that of a sample prepared with conventional compatibilizer, maleic anhydride grafted polyethylene (PE-g-MA).

  • linear low density polyethylene lldpe clay nanocomposites part i structural characterization and quantifying clay dispersion by melt rheology
    Polymer, 2007
    Co-Authors: Ali Durmus, Ahmet Kasgoz, Christopher W Macosko
    Abstract:

    In this study, linear low density polyethylene (LLDPE)/clay nanocomposites with various clay content were prepared by melt processing using two different Compatibilizers, maleic anhydride grafted polyethylene (PE-g-MA) and oxidized polyethylene (OxPE). Effects of structure and physical properties of the Compatibilizers on the clay dispersion and clay amount on the microstructure and physical properties of the nanocomposites were investigated. The OxPE was shown to significantly create interfacial interactions between the polymer phase and clay layers. Rheological behavior of the samples was examined by a dynamic oscillatory rheometry in linear viscoelastic region. Percolation threshold (fp) and corresponding aspect ratio (Af) values were determined by analyzing the improvement in storage modulus at low frequency region depending on the clay loading. Lower percolation and higher aspect ratio values were obtained for the sample series prepared with the PE-g-MA than that prepared with the OxPE. Moreover, fractal size of the clay network above the percolation point was determined by the scaling law for physical gelation of colloidal flocks to quantify clay dispersion depending on the compatibilizer structure. It was found that the PE-g-MA yielded better clay dispersion and more exfoliated structure compared to the OxPE. Microstructural characterization of the samples was also characterized by XRD and TEM. 2007 Elsevier Ltd. All rights reserved.

Ali Durmus - One of the best experts on this subject based on the ideXlab platform.

  • intercalated linear low density polyethylene lldpe clay nanocomposites prepared with oxidized polyethylene as a new type compatibilizer structural mechanical and barrier properties
    European Polymer Journal, 2007
    Co-Authors: Ali Durmus, Maybelle Woo, Ahmet Kasgoz, Christopher W Macosko, Michael Tsapatsis
    Abstract:

    In this study, the use of low molecular weight oxidized polyethylenes (OxPE) with different molecular weight and acid number as a new type of compatibilizer in low density polyethylene (LLDPE)/org-clay nanocomposite preparation was examined. Nanocomposites having 5 phr (part per hundred) org-clay were prepared by melt processing. The effect of compatibilizer polarity and clay dispersion on the thermal, mechanical and barrier properties of the nanocomposites was investigated. It was observed that oxidized polyethylenes created a strong interfacial interaction between the clay layers and polymer phase based on the analysis of the linear viscoelastic behavior of the samples by small amplitude oscillatory rheometry. We showed that physical performance of the nanocomposites is not only affected by clay dispersion but also both melt viscosity and polarity of the oxidized polyethylene Compatibilizers. It was found that oxygen permeability values of the nanocomposite samples prepared with the oxidized polyethylenes were lower than that of a sample prepared with conventional compatibilizer, maleic anhydride grafted polyethylene (PE-g-MA).

  • linear low density polyethylene lldpe clay nanocomposites part i structural characterization and quantifying clay dispersion by melt rheology
    Polymer, 2007
    Co-Authors: Ali Durmus, Ahmet Kasgoz, Christopher W Macosko
    Abstract:

    In this study, linear low density polyethylene (LLDPE)/clay nanocomposites with various clay content were prepared by melt processing using two different Compatibilizers, maleic anhydride grafted polyethylene (PE-g-MA) and oxidized polyethylene (OxPE). Effects of structure and physical properties of the Compatibilizers on the clay dispersion and clay amount on the microstructure and physical properties of the nanocomposites were investigated. The OxPE was shown to significantly create interfacial interactions between the polymer phase and clay layers. Rheological behavior of the samples was examined by a dynamic oscillatory rheometry in linear viscoelastic region. Percolation threshold (fp) and corresponding aspect ratio (Af) values were determined by analyzing the improvement in storage modulus at low frequency region depending on the clay loading. Lower percolation and higher aspect ratio values were obtained for the sample series prepared with the PE-g-MA than that prepared with the OxPE. Moreover, fractal size of the clay network above the percolation point was determined by the scaling law for physical gelation of colloidal flocks to quantify clay dispersion depending on the compatibilizer structure. It was found that the PE-g-MA yielded better clay dispersion and more exfoliated structure compared to the OxPE. Microstructural characterization of the samples was also characterized by XRD and TEM. 2007 Elsevier Ltd. All rights reserved.

Sara Filippi - One of the best experts on this subject based on the ideXlab platform.

  • thermal properties and microhardness of hdpe clay nanocomposites compatibilized by different functionalized polyethylenes
    Polymer Testing, 2009
    Co-Authors: L Minkova, Y Peneva, E Tashev, Sara Filippi, Mariano Pracella, Pierluigi Magagnini
    Abstract:

    Abstract The calorimetric characteristics, the flammability, the thermal stability and the microhardness of polyethylene high density/clay nanocomposites (HDPE/clay) have been studied by differential scanning calorimetry, thermogravimetry, determination of limiting oxygen index and microhardness tests. The nanocomposites have been compatibilized by ethylene–acrylic acid copolymer (EAA), acrylic acid grafted HDPE (HDAA) and maleic anhydride grafted HDPE (HDMA). The clay was montmorillonite Cloisite 15A. The influence of the presence and the type of the Compatibilizers on the properties of the nanocomposites has been evaluated. The results have shown that the thermal stability, the reduction of the flammability and the microhardness of HDPE/clay nanocomposites, compatibilized by HDAA and HDMA are higher than those for nanocomposite compatibilized by EAA. Moreover, the presence and the type of compatibilizer have negligible effect on the characteristics of the HDPE phase transitions. These results have been interpreted by the better clay dispersion and higher level of clay exfoliation in the presence of Compatibilizers HDAA and HDMA, than those in the presence of EAA compatibilizer.

  • reactive compatibilization of pa6 ldpe blends with an ethylene acrylic acid copolymer and a low molar mass bis oxazoline
    Polymer, 2003
    Co-Authors: Roberto Scaffaro, Sara Filippi, Francesco Paolo La Mantia, Loredana Canfora, Giovanni Polacco, Pierluigi Magagnini
    Abstract:

    Abstract A sample of polyamide-6 (PA) was blended with low density polyethylene (LDPE) in the 80/20 wt/wt ratio, either without and with 2 phr of an ethylene–acrylic acid copolymer (EAA), Which was known to behave as a compatibilizer precursor, and the effect of the addition of small amounts (0.2 or 0.35 phr) of a fourth component, 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO), was investigated. The reactions of PBO with EAA, PA and their blends were studied by recording as a function of time the torque applied to the blending apparatuses and by studying the solubility behavior of the products in formic acid. The PALDPE blends were prepared in a co-rotating twin screw extruder and were characterized by Molau tests, differential scanning calorimetry, scanning electron microscopy, rheology, and determination of the ultimate mechanical properties, including impact tests. The results indicate that the effectiveness of EAA as a compatibilizer precursor is considerably enhanced when PBO is added into the blends. It is thought that the reactions of PBO with the free carboxyl groups of EAA and with the amine or carboxyl end groups of PA run, at least in part, toward the formation of PA- g -EAA copolymers acting as the true Compatibilizers for these blends.

  • reactive compatibilization of pa6 ldpe blends with an ethylene acrylic acid copolymer and a low molar mass bis oxazoline
    Polymer, 2003
    Co-Authors: Roberto Scaffaro, Sara Filippi, Francesco Paolo La Mantia, Loredana Canfora, Giovanni Polacco, Pierluigi Magagnini
    Abstract:

    Abstract A sample of polyamide-6 (PA) was blended with low density polyethylene (LDPE) in the 80/20 wt/wt ratio, either without and with 2 phr of an ethylene–acrylic acid copolymer (EAA), Which was known to behave as a compatibilizer precursor, and the effect of the addition of small amounts (0.2 or 0.35 phr) of a fourth component, 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO), was investigated. The reactions of PBO with EAA, PA and their blends were studied by recording as a function of time the torque applied to the blending apparatuses and by studying the solubility behavior of the products in formic acid. The PALDPE blends were prepared in a co-rotating twin screw extruder and were characterized by Molau tests, differential scanning calorimetry, scanning electron microscopy, rheology, and determination of the ultimate mechanical properties, including impact tests. The results indicate that the effectiveness of EAA as a compatibilizer precursor is considerably enhanced when PBO is added into the blends. It is thought that the reactions of PBO with the free carboxyl groups of EAA and with the amine or carboxyl end groups of PA run, at least in part, toward the formation of PA- g -EAA copolymers acting as the true Compatibilizers for these blends.

Ahmet Kasgoz - One of the best experts on this subject based on the ideXlab platform.

  • intercalated linear low density polyethylene lldpe clay nanocomposites prepared with oxidized polyethylene as a new type compatibilizer structural mechanical and barrier properties
    European Polymer Journal, 2007
    Co-Authors: Ali Durmus, Maybelle Woo, Ahmet Kasgoz, Christopher W Macosko, Michael Tsapatsis
    Abstract:

    In this study, the use of low molecular weight oxidized polyethylenes (OxPE) with different molecular weight and acid number as a new type of compatibilizer in low density polyethylene (LLDPE)/org-clay nanocomposite preparation was examined. Nanocomposites having 5 phr (part per hundred) org-clay were prepared by melt processing. The effect of compatibilizer polarity and clay dispersion on the thermal, mechanical and barrier properties of the nanocomposites was investigated. It was observed that oxidized polyethylenes created a strong interfacial interaction between the clay layers and polymer phase based on the analysis of the linear viscoelastic behavior of the samples by small amplitude oscillatory rheometry. We showed that physical performance of the nanocomposites is not only affected by clay dispersion but also both melt viscosity and polarity of the oxidized polyethylene Compatibilizers. It was found that oxygen permeability values of the nanocomposite samples prepared with the oxidized polyethylenes were lower than that of a sample prepared with conventional compatibilizer, maleic anhydride grafted polyethylene (PE-g-MA).

  • linear low density polyethylene lldpe clay nanocomposites part i structural characterization and quantifying clay dispersion by melt rheology
    Polymer, 2007
    Co-Authors: Ali Durmus, Ahmet Kasgoz, Christopher W Macosko
    Abstract:

    In this study, linear low density polyethylene (LLDPE)/clay nanocomposites with various clay content were prepared by melt processing using two different Compatibilizers, maleic anhydride grafted polyethylene (PE-g-MA) and oxidized polyethylene (OxPE). Effects of structure and physical properties of the Compatibilizers on the clay dispersion and clay amount on the microstructure and physical properties of the nanocomposites were investigated. The OxPE was shown to significantly create interfacial interactions between the polymer phase and clay layers. Rheological behavior of the samples was examined by a dynamic oscillatory rheometry in linear viscoelastic region. Percolation threshold (fp) and corresponding aspect ratio (Af) values were determined by analyzing the improvement in storage modulus at low frequency region depending on the clay loading. Lower percolation and higher aspect ratio values were obtained for the sample series prepared with the PE-g-MA than that prepared with the OxPE. Moreover, fractal size of the clay network above the percolation point was determined by the scaling law for physical gelation of colloidal flocks to quantify clay dispersion depending on the compatibilizer structure. It was found that the PE-g-MA yielded better clay dispersion and more exfoliated structure compared to the OxPE. Microstructural characterization of the samples was also characterized by XRD and TEM. 2007 Elsevier Ltd. All rights reserved.