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Carmine Capacchione - One of the best experts on this subject based on the ideXlab platform.

  • stereoselective polymerization of biosourced terpenes β myrcene and β ocimene and their Copolymerization with styrene promoted by titanium catalysts
    Polymer, 2017
    Co-Authors: Marco Naddeo, Antonio Buonerba, Ermanno Luciano, Alfonso Grassi, Antonio Proto, Carmine Capacchione
    Abstract:

    Abstract The stereoselective polymerization of β-myrcene and β-ocimene and their Binary Copolymerization with styrene promoted by titanium complexes dichloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butyl-phenyl)}titanium (1), dichloro{1,4-dithiabutanediyl-2,2′-bis[4,6-bis(2-phenyl-2-propyl)phenoxy]}titanium (2) and Ti(η5-C5H5)-(η2-MBMP)Cl (3) (MBMP = 2,2'methylenebis(6-tert-butyl-4-methylphenoxo)) activated by methylaluminoxane (MAO) is reported. Complex 1 produces a prevalently trans-1,4-polymyrcene (92%), the more sterically encumbered pre-catalyst 2 gives a major amount of 3,4-units (40%). Conversely the pre-catalyst 3 produces cis-1,4-polymyrcene with good selectivity (92%). The catalyst 1 promotes the Copolymerization of β-myrcene with styrene giving the corresponding copolymers in a wide range of composition (χs = 0.14–0.90). In the case of β-ocimene the catalysts 1 and 2 produce a polymer with 1,4-trans structure (70%) at 70 °C while at lower temperature (0 °C) an isotactic poly-1,2-ocimene (>99%) is obtained. The catalyst 3 produces a less stereoregular polymer with prevalently cis-1,4-microstructure (55%). The catalyst 2 also promotes the Copolymerization of β-ocimene with styrene in a wide range of composition (χs = 0.23–0.87).

  • Binary Copolymerization of 4 methyl 1 3 pentadiene with styrene butadiene and isoprene catalysed by a titanium osso type catalyst
    Polymer International, 2017
    Co-Authors: Marianna Loria, Antonio Proto, Carmine Capacchione
    Abstract:

    Binary Copolymerization of 4-methyl-1,3-pentadiene (4MPD) with styrene, butadiene and isoprene promoted by the titanium complex dichloro{1,4-dithiabutanediyl-2,2′-bis[4,6-bis(2-phenyl-2-propyl)phenoxy]}titanium activated by methylaluminoxane is reported. All the copolymers are obtained in a wide range of composition and the molecular weight distributions obtained from gel permeation chromatographic analysis of the copolymers are coherent with the materials being copolymeric in nature. The copolymer microstructure was fully elucidated by means of 1H NMR and 13C NMR spectroscopy. Differential scanning calorimetry shows an increase of glass transition temperature (Tg) with the amount of 4MPD in the copolymers with butadiene and isoprene, while in the copolymers with styrene Tg is increased on increasing the amount of styrene. © 2016 Society of Chemical Industry

  • Binary Copolymerization of p methylstyrene with butadiene and isoprene catalyzed by titanium compounds showing different stereoselectivity
    Macromolecules, 2013
    Co-Authors: Antonio Buonerba, Alfonso Grassi, Antonio Proto, Maria Fienga, Stefano Milione, Cinzia Cuomo, Carmine Capacchione
    Abstract:

    The synthesis of p-methylstyrene–butadiene and p-methylstyrene–isoprene Binary copolymers promoted by the titanium complexes Ti(η5-C5H5)-(κ2-MBMP)Cl (1) (MBMP = 2,2′-methylenebis(6-tert-butyl-4-methylphenoxo)) and chloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butylphenoxy)}titanium (2) activated by methylaluminoxane (MAO) is reported. Syndiotactic poly(p-methylstyrene)-co-cis-1,4-poly(butadiene) and syndiotactic poly(p-methylstyrene)-co-cis-1,4-polyisoprene were obtained using catalyst 1, whereas isotactic poly(p-methylstyrene)-co-trans-1,4-poly(butadiene) and isotactic poly(p-methylstyrene)-co-trans-1,4-polyisoprene were obtained using the catalyst 2. 13C NMR analysis of the copolymer microstructure allowed to assess the monomer block lengths and distribution in the polymer chain, revealing a blocky distribution of the two monomers along the polymer chain in the presence of the catalyst 1 and a random distribution with the catalyst 2 for both Binary copolymers.

Victor E Meyer - One of the best experts on this subject based on the ideXlab platform.

  • computer calculations of Binary and ternary Copolymerization behavior
    Journal of Polymer Science Part C: Polymer Symposia, 2007
    Co-Authors: Richard K S Chan, Victor E Meyer
    Abstract:

    Computer programs in use in our laboratory for the calculation of Binary and ternary Copolymerization behavior are reviewed. In the case of Binary Copolymerization an analytical equation is available, allowing rapid and precise calculations of various parameters of interest. In the case of ternary and higher component systems numerical methods of integration are required. The application of the Runge-Kutta method to ternary Copolymerization systems is outlined. Examples and some of the difficulties encountered with both systems are presented.

Antonio Proto - One of the best experts on this subject based on the ideXlab platform.

  • stereoselective polymerization of biosourced terpenes β myrcene and β ocimene and their Copolymerization with styrene promoted by titanium catalysts
    Polymer, 2017
    Co-Authors: Marco Naddeo, Antonio Buonerba, Ermanno Luciano, Alfonso Grassi, Antonio Proto, Carmine Capacchione
    Abstract:

    Abstract The stereoselective polymerization of β-myrcene and β-ocimene and their Binary Copolymerization with styrene promoted by titanium complexes dichloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butyl-phenyl)}titanium (1), dichloro{1,4-dithiabutanediyl-2,2′-bis[4,6-bis(2-phenyl-2-propyl)phenoxy]}titanium (2) and Ti(η5-C5H5)-(η2-MBMP)Cl (3) (MBMP = 2,2'methylenebis(6-tert-butyl-4-methylphenoxo)) activated by methylaluminoxane (MAO) is reported. Complex 1 produces a prevalently trans-1,4-polymyrcene (92%), the more sterically encumbered pre-catalyst 2 gives a major amount of 3,4-units (40%). Conversely the pre-catalyst 3 produces cis-1,4-polymyrcene with good selectivity (92%). The catalyst 1 promotes the Copolymerization of β-myrcene with styrene giving the corresponding copolymers in a wide range of composition (χs = 0.14–0.90). In the case of β-ocimene the catalysts 1 and 2 produce a polymer with 1,4-trans structure (70%) at 70 °C while at lower temperature (0 °C) an isotactic poly-1,2-ocimene (>99%) is obtained. The catalyst 3 produces a less stereoregular polymer with prevalently cis-1,4-microstructure (55%). The catalyst 2 also promotes the Copolymerization of β-ocimene with styrene in a wide range of composition (χs = 0.23–0.87).

  • Binary Copolymerization of 4 methyl 1 3 pentadiene with styrene butadiene and isoprene catalysed by a titanium osso type catalyst
    Polymer International, 2017
    Co-Authors: Marianna Loria, Antonio Proto, Carmine Capacchione
    Abstract:

    Binary Copolymerization of 4-methyl-1,3-pentadiene (4MPD) with styrene, butadiene and isoprene promoted by the titanium complex dichloro{1,4-dithiabutanediyl-2,2′-bis[4,6-bis(2-phenyl-2-propyl)phenoxy]}titanium activated by methylaluminoxane is reported. All the copolymers are obtained in a wide range of composition and the molecular weight distributions obtained from gel permeation chromatographic analysis of the copolymers are coherent with the materials being copolymeric in nature. The copolymer microstructure was fully elucidated by means of 1H NMR and 13C NMR spectroscopy. Differential scanning calorimetry shows an increase of glass transition temperature (Tg) with the amount of 4MPD in the copolymers with butadiene and isoprene, while in the copolymers with styrene Tg is increased on increasing the amount of styrene. © 2016 Society of Chemical Industry

  • Binary Copolymerization of p methylstyrene with butadiene and isoprene catalyzed by titanium compounds showing different stereoselectivity
    Macromolecules, 2013
    Co-Authors: Antonio Buonerba, Alfonso Grassi, Antonio Proto, Maria Fienga, Stefano Milione, Cinzia Cuomo, Carmine Capacchione
    Abstract:

    The synthesis of p-methylstyrene–butadiene and p-methylstyrene–isoprene Binary copolymers promoted by the titanium complexes Ti(η5-C5H5)-(κ2-MBMP)Cl (1) (MBMP = 2,2′-methylenebis(6-tert-butyl-4-methylphenoxo)) and chloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butylphenoxy)}titanium (2) activated by methylaluminoxane (MAO) is reported. Syndiotactic poly(p-methylstyrene)-co-cis-1,4-poly(butadiene) and syndiotactic poly(p-methylstyrene)-co-cis-1,4-polyisoprene were obtained using catalyst 1, whereas isotactic poly(p-methylstyrene)-co-trans-1,4-poly(butadiene) and isotactic poly(p-methylstyrene)-co-trans-1,4-polyisoprene were obtained using the catalyst 2. 13C NMR analysis of the copolymer microstructure allowed to assess the monomer block lengths and distribution in the polymer chain, revealing a blocky distribution of the two monomers along the polymer chain in the presence of the catalyst 1 and a random distribution with the catalyst 2 for both Binary copolymers.

A E Hamielec - One of the best experts on this subject based on the ideXlab platform.

  • modelling free radical Copolymerization kinetics evaluation of the pseudo kinetic rate constant method 1 molecular weight calculations for linear copolymers
    Die Makromolekulare Chemie Theory and Simulations, 1993
    Co-Authors: Tuyu Xie, A E Hamielec
    Abstract:

    The moment equations for Binary Copolymerization in the context of the terminal model have been solved numerically for a batch reactor operating over a wide range of conditions. Calculated number- and weight-average molecular weights were compared with those found using pseudo-kinetic rate constants with the method of moments and with the instantaneous property method for homopolymerization. With the pseudo-kinetic rate constant method under polymerization conditions where number-average molecular weights (Mn) are below about 103 the error in calculating Mn exceeds 5%. The error increases rapidly with decrease in molecular weight for Mn < 103. Mn measured experimentally for polymer chains (homo- and copolymers) have error limits of greater than ±5% at the 95% confidence level. Therefore, for all practical purposes, the pseudo-kinetic rate constant method is valid for Mn greater than 103. Errors in calculating weight-average molecular weights (Mw) or higher averages are always smaller than those for Mn when applying the pseudo-kinetic rate constant method. The assumptions involved in molecular weight modelling using the pseudo-kinetic rate constant approach are thus proven to be valid, and therefore it is recommended that the pseudo-kinetic rate constant method be employed with the instantaneous property method to calculate the full molecular weight distribution and averages for linear chains synthesized by multicomponent chain growth polymerization.

  • modelling free radical Copolymerization kinetics evaluation of the pseudo kinetic rate constant method 2 molecular weight calculations for copolymers with long chain branching
    Die Makromolekulare Chemie Theory and Simulations, 1993
    Co-Authors: Tuyu Y. Xie, A E Hamielec
    Abstract:

    The full moment equations and equations using pseudo-kinetic rate constants for Binary Copolymerization with chain transfer to polymer in the context of the terminal model have been developed and solved numerically for a batch reactor operating over a wide range of conditions. Calculated number- and weight-average molecular weights (Mn and Mw) were compared with those found using the pseudo-kinetic rate constant method (PKRCM). The results show that the weight-average molecular weights calculated using PKRCM are in agreement with those found using the method of full moments for Binary Copolymerization when polymeric radical fractions φ1˙ and φ2˙ of type 1 and 2 (radical centers are on monomer types 1 and 2 for a Binary Copolymerization) are calculated accounting for chain transfer to small molecules and polymer reactions in addition to propagation reactions. Errors in calculating Mw using PKRCM are not always negligible when polymer radical fractions are calculated neglecting chain transfer to small molecules and polymer. In this case, the relative error in Mw by PKRCM increases with increase in monomer conversion, extent of copolymer compositional drift and chain transfer to polymer rates. The errors in calculating Mw, however, vanish over the entire monomer conversion range for all polymerization conditions when chain transfer reactions are properly taken into account. It is theoretically proven that the pseudo-kinetic rate constant for chain transfer to polymer is valid for Copolymerizations. One can therefore conclude that the pseudo-kinetic rate constant method is a valid method for molecular weight modelling for Binary and multicomponent polymerizations.

Antonio Buonerba - One of the best experts on this subject based on the ideXlab platform.

  • stereoselective polymerization of biosourced terpenes β myrcene and β ocimene and their Copolymerization with styrene promoted by titanium catalysts
    Polymer, 2017
    Co-Authors: Marco Naddeo, Antonio Buonerba, Ermanno Luciano, Alfonso Grassi, Antonio Proto, Carmine Capacchione
    Abstract:

    Abstract The stereoselective polymerization of β-myrcene and β-ocimene and their Binary Copolymerization with styrene promoted by titanium complexes dichloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butyl-phenyl)}titanium (1), dichloro{1,4-dithiabutanediyl-2,2′-bis[4,6-bis(2-phenyl-2-propyl)phenoxy]}titanium (2) and Ti(η5-C5H5)-(η2-MBMP)Cl (3) (MBMP = 2,2'methylenebis(6-tert-butyl-4-methylphenoxo)) activated by methylaluminoxane (MAO) is reported. Complex 1 produces a prevalently trans-1,4-polymyrcene (92%), the more sterically encumbered pre-catalyst 2 gives a major amount of 3,4-units (40%). Conversely the pre-catalyst 3 produces cis-1,4-polymyrcene with good selectivity (92%). The catalyst 1 promotes the Copolymerization of β-myrcene with styrene giving the corresponding copolymers in a wide range of composition (χs = 0.14–0.90). In the case of β-ocimene the catalysts 1 and 2 produce a polymer with 1,4-trans structure (70%) at 70 °C while at lower temperature (0 °C) an isotactic poly-1,2-ocimene (>99%) is obtained. The catalyst 3 produces a less stereoregular polymer with prevalently cis-1,4-microstructure (55%). The catalyst 2 also promotes the Copolymerization of β-ocimene with styrene in a wide range of composition (χs = 0.23–0.87).

  • Binary Copolymerization of p methylstyrene with butadiene and isoprene catalyzed by titanium compounds showing different stereoselectivity
    Macromolecules, 2013
    Co-Authors: Antonio Buonerba, Alfonso Grassi, Antonio Proto, Maria Fienga, Stefano Milione, Cinzia Cuomo, Carmine Capacchione
    Abstract:

    The synthesis of p-methylstyrene–butadiene and p-methylstyrene–isoprene Binary copolymers promoted by the titanium complexes Ti(η5-C5H5)-(κ2-MBMP)Cl (1) (MBMP = 2,2′-methylenebis(6-tert-butyl-4-methylphenoxo)) and chloro{1,4-dithiabutanediyl-2,2′-bis(4,6-di-tert-butylphenoxy)}titanium (2) activated by methylaluminoxane (MAO) is reported. Syndiotactic poly(p-methylstyrene)-co-cis-1,4-poly(butadiene) and syndiotactic poly(p-methylstyrene)-co-cis-1,4-polyisoprene were obtained using catalyst 1, whereas isotactic poly(p-methylstyrene)-co-trans-1,4-poly(butadiene) and isotactic poly(p-methylstyrene)-co-trans-1,4-polyisoprene were obtained using the catalyst 2. 13C NMR analysis of the copolymer microstructure allowed to assess the monomer block lengths and distribution in the polymer chain, revealing a blocky distribution of the two monomers along the polymer chain in the presence of the catalyst 1 and a random distribution with the catalyst 2 for both Binary copolymers.