Characterization and study of microwave activation effects on the polystyrene tacticity

Figueroa-Campos, Josue L.; Monroy-Barreto, Minerva; Palacios‐Alquisira, Joaquín

doi:10.1080/1023666x.2017.1283570

Cited by 3 publications

(1 citation statement)

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“…The tacticity of a polymer is influenced mainly by the catalyst system used, the solvent, Lewis acids, polymerization temperature, and pressure [10][11][12][13]. Many methods have been tested to adjust certain tacticity modes, such as Ziegler-Natta catalysts [14], stereoselective catalytic polymerization [15], and microwave activation [16]. To investigate the influence of tacticity on the polymer's morphology and relate that to the thermo-physical properties, researchers studied simple structure polymers, such as polypropylene and polystyrene.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Chain Tacticity on the Thermal Energy Parameters of Isotactic and Syndiotactic Polypropylene

Nabhan,

Mohammed,

Al-Moameri

et al. 2024

Tikrit j. eng. sci.

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The thermal energy properties in any material affect the substance’s capacity to store or transfer heat. This study investigated the effect of the polymeric chains’ tacticity on the thermal properties of polypropylene related directly to the thermal power, i.e., the heat capacity and thermal conductivity. The study selected different commercial polypropylene groups with two steric modes: isotactic and syndiotactic. The aim is to determine the parameters: isotacticity index, degree of crystallinity, glass-transition temperature, melting point, heat capacity, and thermal conductivity. The data were collected using gel permeation chromatography (GPC), nuclear magnetic resonance (NMR), and differential scanning calorimetry (DSC). The results showed that methyl groups randomly distributed within the homo-polypropylene changed the overall content of meso diads, i.e., less isotacticity index. The differences between isotactic and syndiotactic polypropylene groups were 20-40% the degree of the crystallinity, 5-10°C the glass-transition temperature, and 10-20°C the melting point. Using suitable mathematical models, these parameters can be related directly to specific heat capacity and thermal conductivity.

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