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John W. Wheeler - One of the best experts on this subject based on the ideXlab platform.

  • Polyamides incorporating phosphine oxide groups. III. Polymerisation of bis [4- (2-aminoethyl) aminophenyl] - phenylphosphine oxide with dicarboxylic acids
    Journal of Polymer Science Part A: Polymer Chemistry, 1997
    Co-Authors: Yuehua Zhang, John C. Tebby, John W. Wheeler
    Abstract:

    The new Polymerisation Monomer bis[4-(2-aminoethyl)aminophenyl]-phenylphosphine oxide (p-BAPPO) was prepared in good yield by the nucleophilic substitution reaction between bis(4-fluorophenyl)phenylphosphine oxide and a large excess of 1,2-diaminoethane. Five novel polyamides, incorporating phosphine oxide groups within the polymer backbone were synthesised by the condensation reaction of p-BAPPO with a series of aromatic and aliphatic dicarboxylic acids. The thermal properties of these polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. Glass transition temperatures in the 180-215°C range were recorded. Although we observed their thermooxidative stabilities (5% weight loss > 345°C) to be lower by 40-70°C than those previously found for wholly aromatic polyamides with phosphine oxide groups within the parent chain, char yields upon prolonged heating at 650°C were still excellent (26-38%). Also, good solubility in aprotic polar solvents was observed for all polyamides synthesised. The new polyamides clearly represent significant progress in the quest for processible fire retardant materials.

Yuehua Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Polyamides incorporating phosphine oxide groups. III. Polymerisation of bis [4- (2-aminoethyl) aminophenyl] - phenylphosphine oxide with dicarboxylic acids
    Journal of Polymer Science Part A: Polymer Chemistry, 1997
    Co-Authors: Yuehua Zhang, John C. Tebby, John W. Wheeler
    Abstract:

    The new Polymerisation Monomer bis[4-(2-aminoethyl)aminophenyl]-phenylphosphine oxide (p-BAPPO) was prepared in good yield by the nucleophilic substitution reaction between bis(4-fluorophenyl)phenylphosphine oxide and a large excess of 1,2-diaminoethane. Five novel polyamides, incorporating phosphine oxide groups within the polymer backbone were synthesised by the condensation reaction of p-BAPPO with a series of aromatic and aliphatic dicarboxylic acids. The thermal properties of these polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. Glass transition temperatures in the 180-215°C range were recorded. Although we observed their thermooxidative stabilities (5% weight loss > 345°C) to be lower by 40-70°C than those previously found for wholly aromatic polyamides with phosphine oxide groups within the parent chain, char yields upon prolonged heating at 650°C were still excellent (26-38%). Also, good solubility in aprotic polar solvents was observed for all polyamides synthesised. The new polyamides clearly represent significant progress in the quest for processible fire retardant materials.

John C. Tebby - One of the best experts on this subject based on the ideXlab platform.

  • Polyamides incorporating phosphine oxide groups. III. Polymerisation of bis [4- (2-aminoethyl) aminophenyl] - phenylphosphine oxide with dicarboxylic acids
    Journal of Polymer Science Part A: Polymer Chemistry, 1997
    Co-Authors: Yuehua Zhang, John C. Tebby, John W. Wheeler
    Abstract:

    The new Polymerisation Monomer bis[4-(2-aminoethyl)aminophenyl]-phenylphosphine oxide (p-BAPPO) was prepared in good yield by the nucleophilic substitution reaction between bis(4-fluorophenyl)phenylphosphine oxide and a large excess of 1,2-diaminoethane. Five novel polyamides, incorporating phosphine oxide groups within the polymer backbone were synthesised by the condensation reaction of p-BAPPO with a series of aromatic and aliphatic dicarboxylic acids. The thermal properties of these polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. Glass transition temperatures in the 180-215°C range were recorded. Although we observed their thermooxidative stabilities (5% weight loss > 345°C) to be lower by 40-70°C than those previously found for wholly aromatic polyamides with phosphine oxide groups within the parent chain, char yields upon prolonged heating at 650°C were still excellent (26-38%). Also, good solubility in aprotic polar solvents was observed for all polyamides synthesised. The new polyamides clearly represent significant progress in the quest for processible fire retardant materials.

Andrea Carletto - One of the best experts on this subject based on the ideXlab platform.

  • In situ mass spectrometry of polymerising pulsed plasmas
    2019
    Co-Authors: Andrea Carletto
    Abstract:

    Pulsed plasma Polymerisation provides an efficient method for the functionalisation of solid surfaces. In comparison to continuous wave plasma conditions, it causes limited Monomer fragmentation and leads to high levels of structural retention. Diagnostic studies on such systems have become increasingly common establishing plasma diagnostic techniques as a powerful tool to garner a deeper understanding of the chemistry on which these pulsed plasma deposition processes rely on. In this work, in situ time-resolved mass spectrometry was employed, operating in both ion and radical species detection mode, to explore the complex nature of the chemical reactions occurring in the plasma phase. The intent of this project is gain insight into reaction pathways of pulsed plasmas, and draw comparisons between conventional step-growth Polymerisation (Monomer-Monomer addition) and pulsed plasma Polymerisation routes. Common Monomer precursors were investigated under pulsed plasma conditions, namely; 1-decene, allyl glycidyl ether (AGE), hexafluoropropylene oxide (HFPO), glycidyl methacrylate (GMA), maleic anhydride (MAH) and butyl acrylate (BA). The experimental results confirm that step-growth Polymerisation occurs in the plasma phase, via two distinct plasma environments as identified by time-resolved mass spectrometry. Importantly, pulsing electric discharges is demonstrated to limit the Monomer fragmentation so that the chemical features of the original Monomer precursor remain intact leading to structurally well-defined plasma polymers. Such findings corroborate the results obtained from the characterisation of resulting plasma polymer films that can be found in the literature.

Anjali Awasthi - One of the best experts on this subject based on the ideXlab platform.

  • Modelling of Butyl Acrylate Emulsion Polymerisation: A Detailed Lumped Parameter Approach
    Indian Chemical Engineer, 2014
    Co-Authors: Ashwini Sood, Ranjana Bharti, Anjali Awasthi
    Abstract:

    AbstractAn extensive lumped model was developed for butyl acrylate emulsion Polymerisation. Monomer volume fraction in the particle was calculated using a thermodynamic equation and the average number of radicals per particle was calculated according to a relationship given for the pseudo-bulk kinetics. The model also incorporated both the micellar and the homogeneous nucleation phenomena and incorporated individual oligomer balances for radicals arising from initiator decomposition and further propagation in the aqueous phase. The model also explored the effects on Polymerisation kinetics of including radical exited from the particles in the aqueous phase radical balance. The effects of considering entry in the micelles and the particles of only radicals of a certain chain length were also studied. The model was validated against the experimental data taken from the literature.