Study of isocyanate group opening initiated by potassium polyoxyethylene glycolate

Davletbaeva, I. M.; Шкодич, В Ф; Ekimova, E. O.; Gumerov, A. M.

doi:10.1134/s0965545x07080056

Cited by 6 publications

(4 citation statements)

References 7 publications

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“…[60] Potassium polyoxyethylene glycolates (PEGÀ K, 37) catalyzed linear polymerization of phenyl isocyanate via an anionic pathway at 30 °C in carbon tetrachloride while formation of isocyanurate from back-biting of isocyanate polymer was only observed with a very low rate constant. [61] Alkali metal cyanates (MOCN, M=Li, Na, K, 38) reacted with organic isocyanates and provided the metal isocyanuric acid salts in dipolar aprotic solvents, during which the isocyanurate was formed as a side product. [62] Alkyl isocyanates formed more isocyanurate (> 50 %) than aryl isocyanates (< 50 %), and the formation of isocyanurate increased with higher isocyanate concentration as well as addition of electrolyte.…”

Section: Lewis Basic Catalystsmentioning

confidence: 99%

“…Certain acyl aminimides with hydroxyl groups ( 36 ) are active cyclotrimerization catalysts; primary hydroxy groups are more active than secondary hydroxy groups [60] . Potassium polyoxyethylene glycolates (PEG−K, 37 ) catalyzed linear polymerization of phenyl isocyanate via an anionic pathway at 30 °C in carbon tetrachloride while formation of isocyanurate from back‐biting of isocyanate polymer was only observed with a very low rate constant [61] . Alkali metal cyanates (MOCN, M=Li, Na, K, 38 ) reacted with organic isocyanates and provided the metal isocyanuric acid salts in dipolar aprotic solvents, during which the isocyanurate was formed as a side product [62] .…”

Section: Catalysts Operating Via Lewis Basic Cyclotrimerization Mecha...mentioning

confidence: 99%

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Catalysts for Isocyanate Cyclotrimerization

et al. 2023

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The formation of isocyanurate via cyclotrimerization of isocyanates is widely reported to provide a variety of polyurethane materials with improved chemical and physical properties such as weatherability, mechanical properties, thermal stability and flame retardancy. The demand for development of effective and selective catalysts for cyclotrimerization of isocyanates has been increasing. This review comprehensively summarizes catalysts for the cyclotrimerization of isocyanates that have been reported in peer‐reviewed publications and provides a valuable guideline for choosing suitable catalysts to match specific requirements. The catalysts are categorized into two main classes: catalysts operating via a Lewis basic cyclotrimerization mechanism and metal‐containing catalysts. Catalyst structures, reaction conditions, reaction time, catalytic effectivity as well as types of isocyanates whose trimerization is catalyzed are described in detail. In addition, featuring the findings and viewpoints from mechanistic studies, this review aims to stimulate the design and development of new, more efficient catalysts, and to guide further study of the trimerization mechanism with different classes of catalysts.

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Section: Lewis Basic Catalystsmentioning

confidence: 99%

Section: Catalysts Operating Via Lewis Basic Cyclotrimerization Mecha...mentioning

confidence: 99%

Catalysts for Isocyanate Cyclotrimerization

et al. 2023

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“…In [12,13] it was established that the open chain analogs of crown ethers, which are block copolymers of ethylene oxide and propylene oxide containing terminal and potassium alcoholate groups, are effective initiators of opening the isocyanate groups along the thermodynamically more stable carbonyl group. It was assumed that the capture of the metal cation by polyester fragment acting as a linear podand promotes the preferential localization of the negative charge on the oxygen atom of the growing chain in anionic polymerization.…”

Section: Fundamentals Of Synthesis Of Mesoporous Polymers Based On Armentioning

confidence: 99%

Optical Sensors Based on Mesoporous Polymers

Davletbaev¹,

Akhmetshina²,

Gumerov³

et al. 2014

Optical Sensors - New Developments and Practical Applications

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“…[14][15][16] It was assumed [15,16] that the capture of a metal cation by a polyether fragment, performing the role of a linear podand, promoted the preferred localization of a negative charge on an oxygen atom of the growing chain during the anionic polymerization ( Figure 1). …”

Section: Introductionmentioning

confidence: 99%

Supramolecular architecture of polymers as the basis of obtaining mesoporous polymers

Davletbaev

Akhmetshina

Gumerov

et al. 2014

Composite Interfaces

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Self-organization and arrangement of supramolecular structures from blockcopolymers are some of the ways used for the development of nanoporous and mesoporous polymers. Herein, reactive olygomers can play the key role in the design of supramolecular arranging of polymers. Optically transparent mesoporuos block-copolymers with adjusted free volume are obtained by the polyaddition of 2,4-toluene diisocyanate (TDI) to anionic macroinitiators. The mechanism of polyaddition of TDI to an anionic macroinitiator in various chemical solvents was studied by infrared spectroscopy. It is established that the reaction of forming polyisocyanate blocks of acetal nature (O-polyisocyanate) and stabilization of end O-polyisocyanate chains are based on the formation of voids in polymer. The formation of voids is conditioned by the geometry of self-organization of block-copolymers containing end potassium-O-polyisocyanates stabilized by crown ether fragments. The formation of urea with the participation of isocyanate groups of ortho-location of TDI is one of the main factors of the stabilization of O-polyisocyanate blocks. The investigation of the polymer sorption properties was carried out by electron spectroscopy. As an adsorbed dye Rhodamine 6G was used. The ability of Rhodamine 6G to sorb depended on the content of the O-polyisocyanate component in the polymer. Mesoporous polymers demonstrated high efficiency as an optically transparent matrix for laser-active media with high radiation stability. Rhodamine 6G in mesoporous polymers retains spectral luminescent properties and generates laser radiation during excitation by the second harmonic of Nd:YAG laser.

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Study of isocyanate group opening initiated by potassium polyoxyethylene glycolate

Cited by 6 publications

References 7 publications

Catalysts for Isocyanate Cyclotrimerization

Catalysts for Isocyanate Cyclotrimerization

Optical Sensors Based on Mesoporous Polymers

Supramolecular architecture of polymers as the basis of obtaining mesoporous polymers

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