Lewis Acid – Complexed Tetramethylene Biradicals Can Initiate the Thermal Copolymerization of Indene with Acrylonitrile

Choi, Woon-Seop; Han, Xue; Hall, H. K.

doi:10.1007/s00289-005-0380-7

Cited by 2 publications

(2 citation statements)

References 19 publications

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“…This dimerization is followed by a hydrogen atom abstraction by another S molecule to form two initiating monoradicals. Detection of an accompanying cycloadduct,7 and some mechanistic behavior when acid catalysts8 are present, supports the Mayo mechanism for S. In an earlier mechanism proposed by Flory for S spontaneous polymerization,9 the two monomer molecules generate a tetramethylene diradical intermediate by bond formation between two β‐carbons. This diradical may actually ring‐close to form either a Mayo dimer, which can then transfer hydrogen and initiate free radical polymerization, or the 1,2‐diphenylcyclobutane derivative, a species that is inactive to polymerization 9.…”

Section: Introductionsupporting

confidence: 52%

Mechanism and Kinetics of the Spontaneous Thermal Copolymerization of Styrene/Maleic Anhydride. Experimental and Simulation Studies in the Presence of 4‐oxo‐TEMPO

Mota‐Morales

Quintero-Ortega

Saldívar‐Guerra

et al. 2010

Macro Reaction Engineering

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The mechanism and kinetics of the spontaneous copolymerization of styrene (S) and maleic anhydride (MA) in the presence of 4‐oxo‐TEMPO nitroxide (N) were studied. Experiments were performed at 125 °C varying the S/MA and the N/S ratios and the evolution of conversion was measured by dilatometry up to 20% conversion. Clean induction periods or severe retardation in the initial stage of the reaction were observed. From a proposed kinetic mechanism a mathematical model was built, which was used for fitting the relevant kinetic constants for the self‐initiation steps, and the ratio ${{\bar {k}_{\rm p} } \mathord{\left/ {\vphantom {{\bar {k}_{\rm p} } {\bar {k}_{\rm t}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} }}} \right. \kern-\nulldelimiterspace} {\bar {k}_{\rm t}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} }}$. The model performs well in certain concentration regimes, but it remains a challenge to completely understand this complex system in other concentration regimes.

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Section: Introductionsupporting

confidence: 52%

Mechanism and Kinetics of the Spontaneous Thermal Copolymerization of Styrene/Maleic Anhydride. Experimental and Simulation Studies in the Presence of 4‐oxo‐TEMPO

Mota‐Morales

Quintero-Ortega

Saldívar‐Guerra

et al. 2010

Macro Reaction Engineering

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“…In totally analogous fashion, on reacting 2,3‐dimethylbutadiene with acrylonitrile in the presence of zinc chloride as the Lewis acid, free radical copolymerization competed with concerted cycloadditions; higher rates were observed with than without Lewis acid 74. These reactions were also investigated using 1‐methylbutadiene, 1,1‐dimethylbutadiene, and indene as the dienes, acrylonitrile and methyl acrylate as the electrophilic olefin, and lithium perchlorate or zinc chloride as the Lewis acid (refs 75,7677…”

Section: Introductionmentioning

confidence: 99%