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Intercalative Polymerization (intercalative + polymerization)

Distribution by Scientific Domains
Polymers and Materials Science100%

Kinds of Intercalative Polymerization

  • situ intercalative polymerization
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    Selected Abstracts

    Polystyrene/Montmorillonite Nanocomposites Prepared by In Situ Intercalative Polymerization: Influence of the Surfactant Type

    MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 17 2004
    Hisham A. Essawy
    Abstract Summary: Na-montmorillonite (MMT) with a cation exchange capacity (CEC) of 90 meq/100 g was converted to MMT-CTAB and MMT-CPC by the intercalation of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), respectively. The intercalation of CPC onto the basal space of the montmorillonite expanded the basal space from 12.19 to 21.47 Å, whereas in the case of CTAB, the spacing was only expanded to 19.35 Å. The MMT-CPC and MMT-CTAB forms were subsequently used as hosts for the preparation of polystyrene nanocomposites via intercalative free-radical polymerization of styrene. Different structures were obtained by varying the preparation conditions; the exfoliated and intercalated nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and differential scanning calorimeter (DSC). The produced nanocomposites exhibited improved thermal stability in comparison with that of pure polystyrene above 400,°C especially in the case of the nanocomposites based on the MMT-CPC, in which intercalation exists. A glass transition temperature (Tg) could not be detected for the prepared nanocomposites using DSC; this was assumed to result from the restricted molecular motion of the polymer chains. XRD pattern of PS nanocomposites prepared by intercalative polymerization. [source]

    Isotactic Poly(propylene)/Monoalkylimidazolium-Modified Montmorillonite Nanocomposites: Preparation by Intercalative Polymerization and Thermal Stability Study

    MACROMOLECULAR RAPID COMMUNICATIONS, Issue 24 2004
    Aihua He
    Abstract Summary: Poly(propylene)/monoalkylimidazolium-modified montmorillonite (PP/IMMT) nanocomposites were prepared by in situ intercalative polymerization of propylene with TiCl4/MgCl2/MMT catalyst. The PP synthesized possessed high isotacticity and molecular weight. Both wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) examinations evidenced the nanocomposite formation with exfoliated MMT homogeneously distributed in the PP matrix. A thermal stability study revealed that the nanocomposites possess good thermal stability. X-ray diffraction patterns of PP/IMMT (MMT,=,2.2 wt.-%) nanocomposite before and after processing. [source]

    Synthesis and characterization of novel poly(o -toluidine) montmorillonite nanocomposites: Effect of surfactant on intercalation

    JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007
    Rahul Singhal
    Abstract The investigation of clay based polymer nanocomposites has opened the door for the development of novel, ecofriendly advanced nano materials that can be safely recycled. Because of their nanometer size dispersion, these nanocomposites often have superior physical and mechanical properties. In this study, novel nanocomposites of poly(o -toluidine) (POT) and organically modified montmorillonite (MMT) were synthesized using camphor sulfonic acid (CSA), cetyl pyridinum chloride (CPCl), and N -cetyl- N,N,N -trimethyl ammonium bromide (CTAB) to study the role of surfactant modification on the intercalation. The in situ intercalative polymerization of POT within the organically modified MMT layers was analyzed by FTIR, UV,visible, XRD, SEM as well as TEM studies. The average particle size of the nanocomposites was found to be in the range 80,100 nm. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source]

    Polystyrene/Montmorillonite Nanocomposites Prepared by In Situ Intercalative Polymerization: Influence of the Surfactant Type

    MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 17 2004
    Hisham A. Essawy
    Abstract Summary: Na-montmorillonite (MMT) with a cation exchange capacity (CEC) of 90 meq/100 g was converted to MMT-CTAB and MMT-CPC by the intercalation of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), respectively. The intercalation of CPC onto the basal space of the montmorillonite expanded the basal space from 12.19 to 21.47 Å, whereas in the case of CTAB, the spacing was only expanded to 19.35 Å. The MMT-CPC and MMT-CTAB forms were subsequently used as hosts for the preparation of polystyrene nanocomposites via intercalative free-radical polymerization of styrene. Different structures were obtained by varying the preparation conditions; the exfoliated and intercalated nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and differential scanning calorimeter (DSC). The produced nanocomposites exhibited improved thermal stability in comparison with that of pure polystyrene above 400,°C especially in the case of the nanocomposites based on the MMT-CPC, in which intercalation exists. A glass transition temperature (Tg) could not be detected for the prepared nanocomposites using DSC; this was assumed to result from the restricted molecular motion of the polymer chains. XRD pattern of PS nanocomposites prepared by intercalative polymerization. [source]

    Isotactic Poly(propylene)/Monoalkylimidazolium-Modified Montmorillonite Nanocomposites: Preparation by Intercalative Polymerization and Thermal Stability Study

    MACROMOLECULAR RAPID COMMUNICATIONS, Issue 24 2004
    Aihua He
    Abstract Summary: Poly(propylene)/monoalkylimidazolium-modified montmorillonite (PP/IMMT) nanocomposites were prepared by in situ intercalative polymerization of propylene with TiCl4/MgCl2/MMT catalyst. The PP synthesized possessed high isotacticity and molecular weight. Both wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) examinations evidenced the nanocomposite formation with exfoliated MMT homogeneously distributed in the PP matrix. A thermal stability study revealed that the nanocomposites possess good thermal stability. X-ray diffraction patterns of PP/IMMT (MMT,=,2.2 wt.-%) nanocomposite before and after processing. [source]

    Preparation and properties of polyurethane/montmorillonite nanocomposites cured under room temperature

    POLYMER COMPOSITES, Issue 5 2006
    Hangbin Jiang
    The polyurethane/C16C18 -MMT (the montmorillonite modified with cetyloctadecyldimethyl ammonium bromide) nanocomposites were synthesized by intercalative polymerization and cured under room temperature. The d -spacing and the dispersion of the C16C18 -MMT in the nanocomposites were measured by X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM). The mechanical and thermal properties of the nanocomposites were measured by Universal Testing System, Electric Anti-fold Instrument, Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). It was found out that introducing C16C18 -montmorillonite (MMT) in the polyurethane (PU) displayed good mechanical properties and thermal stability. Rheology behavior in liquid state showed that the addition of the C16C18 -MMT to PU resulted in low gel time and high viscosity. POLYM. COMPOS. 27:470,474, 2006. © 2006 Society of Plastics Engineers. [source]

    Biodegradable polyester layered silicate nanocomposites based on poly(,-caprolactone)

    POLYMER ENGINEERING & SCIENCE, Issue 9 2002
    Nadège Pantoustier
    Nanocomposites based on biodegradable poly(,-caprolactone) (PCL) and layered silicates (montmorillonite, MMT) were prepared either by melt interaction with PCL or by in situ ring-opening polymerization of ,-caprolactone as promoted by the so-called coordination-insertion mechanism. Both non-modified clays (Na+ -MMT) and silicates modified by various alkylammonium cations were studied. Mechanical and thermal properties were examined by tensile testing and thermogravimetric analysis. Even at a filler content as low as 3 wt% of inorganic layered silicate, the PCL-layered silicate nanocomposites exhibited improved mechanical properties (higher Young's modulus) and increased thermal stability as well as enhanced flame retardant characteristics as a result of a charring effect. It was shown that the formation of PCL-based nanocomposites depended not only on the nature of the ammonium cation and related functionality but also on the selected synthetic route, melt intercalation vs. in situ intercalative polymerization. Interestingly enough, when the intercalative polymerization of ,-caprolactone was carried out in the presence of MMT organo-modified with ammonium cations bearing hydroxyl functions, nanocomposites with much improved mechanical properties were recovered. Those hybrid polyester layered silicate nanocomposites were characterized by a covalent bonding between the polyester chains and the clay organo-surface as a result of the polymerization mechanism, which was actually initiated from the surface hydroxyl functions adequately activated by selected tin (II) or tin (IV) catalysts. [source]

    Preparation and swelling behavior of amphoteric superabsorbent composite with semi-IPN composed of poly(acrylic acid)/Ca-bentonite/poly(dimethyldiallylammonium chloride)

    POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 3 2007
    Liuchun Zheng
    Abstract Amphoteric superabsorbent composite with semi-interpenetrating polymer networks (semi-IPN) composed of poly(acrylic acid) (PAA)/Ca-bentonite/poly(dimethyldiallylammonium chloride) (PDMDAAC) was prepared by a combination of intercalative polymerization and a sequential IPN method and the effects of reaction parameters on the swelling capacity were studied. PDMDAAC was used as a polycation to modify bentonite and form semi-IPN with lightly crosslinked PAA. FTIR and TG were used to characterize the amphoteric superabsorbent composites with semi-IPN. The thermal stability of the product was not degraded as in the case of using small molecular surfactant to modify bentonite. The contents of carboxylic groups and nitrogen had been determined. This indicated that the product with certain content of carboxylic groups and nitrogen is inclined to exhibit excellent swelling capacity. The presence of PDMDAAC improved the swelling capacity. The resulting amphoteric superabsorbent composite showed excellent swelling capacity of 1578,g/g in distilled water and 136,g/g in 0.9,wt% NaCl solution. Copyright © 2007 John Wiley & Sons, Ltd. [source]