Cyclic ethylene phosphates with (CH2)nCOOR and CH2CONMe2 substituents: synthesis and mechanistic insights of diverse reactivity in aryloxy-Mg complex-catalyzed (co)polymerization

Nifant’ev, Ilya E.; Shlyakhtin, Andrey V.; Bagrov, Vladimir V.; Tavtorkin, Alexander N.; Ilyin, Sergey O.; Gavrilov, Dmitry; Ivchenko, Pavel V.

doi:10.1039/d1py01277k

Cited by 2 publications

(1 citation statement)

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“…The controlled synthesis of polymers with long-chain branching has become a common practice in the plastics industry since it increases the flow activation energy and melt elasticity of polymers, which is substantial in their processing. − The other popular approach consists in mixing linear and long-chain branched polymers (especially polyolefins) for producing polymer pipes, films, and other extrusion products. − When mixing linear and long-chain branched polymers, miscible blends are formed. , However, it can be expected that an increase in the branching degree with a transition to hyperbranched macromolecules may yield an immiscible blend with their linear macromolecular analogues . Such immiscible blends may be of interest to the industry since their melts represent microemulsions with low interfacial tension and such heterogeneous morphology passes to extruded products, improving their impact and damping characteristics , and giving new optical properties.…”

Section: Introductionmentioning

confidence: 99%

Rheology and Miscibility of Linear/Hyperbranched Polydimethylsiloxane Blends and an Abnormal Decrease in Their Viscosity

Ilyin,

Kulichikhin

2023

Macromolecules

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Linear polymers with the same monomer units and different molecular weights form miscible blends considered to be single polymers, but the situation changes if one is hyperbranched. Hyperbranched macromolecules can significantly change the rheology of a linear polymer due to a different flow mechanism and can even lead to the formation of immiscible or partially miscible blends with unusual mechanical properties due to the emulsion state and low droplet–matrix interfacial tension. Blends of hyperbranched polydimethylsiloxane (silicone MT resin, H-PDMS) with similar linear polymers (L-PDMS) of different molecular weights in a concentration range from 20 to 80% have been studied in this work. Laser interferometry of the diffusion zone between H-PDMS and L-PDMS showed their limited miscibility that is improving with decreasing molecular weight of the linear polymer, leading to a decrease in the upper critical solution temperature. The solubility of H-PDMS in L-PDMS is much higher than that of L-PDMS in H-PDMS (20–50% versus 1–2% at 25 °C, depending on the molecular weight of L-PDMS), and H-PDMS emulsifies in L-PDMS but not vice versa. As a result, the partially miscible blends are emulsions of almost pure H-PDMS in a saturated H-PDMS/L-PDMS solution, even at an H-PDMS concentration as high as 80%. The thermorheological behavior of blends was described using an averaged combination of the Arrhenius and Williams–Landel–Ferry equations, allowing for overcoming the large difference in the glass transition temperatures of hyperbranched and linear macromolecules. The viscosity of blends with a higher-molecular-weight L-PDMS has a positive deviation from the log-additivity rule due to macromolecular entanglements, while a decrease in the molecular weight of L-PDMS causes an abnormal drop in viscosities below those of pure polymers. The anomalous decrease in viscosity appears only in a specific temperature range and is explained by mixing a polymer with a high glass transition temperature and high flow activation energy (H-PDMS) with one having lower values of these characteristics (L-PDMS).

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Section: Introductionmentioning

confidence: 99%

Rheology and Miscibility of Linear/Hyperbranched Polydimethylsiloxane Blends and an Abnormal Decrease in Their Viscosity

Ilyin,

Kulichikhin

2023

Macromolecules

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Synthesis, molecular structure and catalytic performance of heterocycle-fused cyclopentadienyl-amido CGC of Ti (IV) in ethylene (co)polymerization: The formation and precision rheometry of long-chain branched polyethylenes

Nifant’ev

Vinogradov

et al. 2022

European Polymer Journal

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Cyclic ethylene phosphates with (CH₂)_nCOOR and CH₂CONMe₂ substituents: synthesis and mechanistic insights of diverse reactivity in aryloxy-Mg complex-catalyzed (co)polymerization

Abstract: Herein we present a comparative study of the reactivity of ethylene phosphates with –O(CH2)nCOOMe (n = 1–3, 5), –CH2COOtBu, –OCHMeCOOMe, and –OCH2CONMe2 substituents in BHT-Mg catalyzed ROP.

Cited by 2 publications

References 101 publications

Rheology and Miscibility of Linear/Hyperbranched Polydimethylsiloxane Blends and an Abnormal Decrease in Their Viscosity

Rheology and Miscibility of Linear/Hyperbranched Polydimethylsiloxane Blends and an Abnormal Decrease in Their Viscosity

Synthesis, molecular structure and catalytic performance of heterocycle-fused cyclopentadienyl-amido CGC of Ti (IV) in ethylene (co)polymerization: The formation and precision rheometry of long-chain branched polyethylenes

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