Reaction Kinetics of Polyurethane Formation Using a Commercial Oligomeric Diisocyanate Resin Studied by Calorimetric and Rheological Methods

Papadopoulos, Eleni; Ginic‐Markovic, Milena; Clarke, Stephen

doi:10.1002/macp.200800345

Cited by 21 publications

(15 citation statements)

References 49 publications

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“…Fernandez d'Arlas et al applied DSC and Fourier transform spectroscopy for determining reaction rate of polycarbonate‐ co ‐esterdiol and diisocyanate . Papadopoulos et al reported reaction rates as well as factors for a diisocyanate polyurethane by calorimetric and rheological methods …”

Section: Introductionmentioning

confidence: 99%

Reaction modeling of urethane polyols using fraction primary secondary and hindered‐secondary hydroxyl content

Ghoreishi

Zhao

Suppes

2014

J of Applied Polymer Sci

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The effect of primary, secondary, and hindered‐secondary hydroxyl groups on reactions and temperature profiles of polyurethane gels was investigated and modeled using a computer simulation that simultaneously solves over a dozen differential equations. Using urethane gel reaction temperature profiles of the reference compounds 1‐pentanol, 2‐pentanol, and Voranol 360 reactivity parameters were determined for reference primary, secondary, and hindered‐secondary hydroxyl moieties. The reaction parameters, including Arrhenius constants and heats of reaction, were consistent with previous values reported in literature. The approach of using fractions primary, secondary, and hindered‐secondary hydroxyl content to characterize reactivity sets the basis for a powerful approach to simulating/predicting urethane reaction performance with limited data on new polyols and catalysts. This code can be used for all polyols, as the kinetic parameters are based on the fraction primary, secondary, and hindered‐secondary alcohol moieties, not the type of the polyol. Kinetic parameters are also specific to catalysts where at least one parameter specific to each catalyst is necessary to simulate the impact of that catalyst. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40388.

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Section: Introductionmentioning

confidence: 99%

Reaction modeling of urethane polyols using fraction primary secondary and hindered‐secondary hydroxyl content

Ghoreishi

Zhao

Suppes

2014

J of Applied Polymer Sci

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“…The two stages seen in Figure 6 arise from the difference in reactivity of the primary and secondary hydroxyl groups in the glycerol as was established using DSC. Furthermore, at each of these two stages of viscosity build up, a change in the rate is noticed, which is apparent due to the difference in reactivity of the terminal isocyanate groups to the internal isocyanate groups of the varying weight oligomers in PMDI 22. Sekkar et al48 observed a similar rate change due to the difference in reactivity of isocyanate functional groups using toluene diisocyanate.…”

Section: Resultsmentioning

confidence: 90%

“…The advanced integral isoconversional method developed by Vyazovkin20 states that at constant conversion the rate of reaction is only a function of temperature and allows the activation energy to be determined without choosing a reaction model. Isoconversional analysis has previously been used to describe the crosslinking reaction for a limited number of complex polyurethane systems 2, 21, 22. Differential scanning calorimetry (DSC) has been widely used to study thermoset reactions in both isothermal and nonisothermal modes 4, 23–27.…”

Section: Introductionmentioning

confidence: 99%

A thermal and rheological investigation during the complex cure of a two‐component thermoset polyurethane

Papadopoulos

Ginic‐Markovic

Clarke

2009

J of Applied Polymer Sci

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ABSTRACT:The complex cure kinetics of the reaction between oligomeric diphenylmethane diisocyanate (PMDI) and glycerol was characterized through thermal and rheological techniques. Isoconversional analysis of Differential scanning calorimetry (DSC) data resulted in the activation energy varying with conversion. Isothermal analysis gave activation energies ranging from 5 kJ/mol to 33.7 kJ/ mol, whereas nonisothermal data gave values for the activation energy ranging from 49.5 to 55 kJ/mol. Incomplete cure was evident in isothermal DSC, becoming diffusion controlled in the final stages of cure. DMA analysis on the cured material gave a glass transition temperature of 104 AE 3 C, which was evidence for vitrification of the curing system. The primary and secondary hydroxyl group reactivity was dependant on the isothermal cure temperature. Rheological studies of viscosity increase and tan d changes with time revealed a complex cure process, with primary and secondary hydroxyl reactivity also showing dependence on isothermal cure temperatures, reflecting similar results obtained from isothermal DSC studies. The independence of tan d on frequency was used to determine the point where the polymer formed an infinite network and was no longer able to flow, providing an overall activation energy attained at the gel point of 77.4 AE 4.4 kJ/mol.

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“…The first step of the dual-curing process was conducted at 60°C and the second one at 120°C. The characteristic absorbance peak of the isocyanate at 2280 cm −1 (vibration of N C O groups) was used to monitor the conversion of the isocyanate group during thiol-isocyanate reaction [23]. The disappearance of the absorbance peak at 915 cm −1 was used to monitor the reaction of epoxy groups [24].…”

Section: Characterization Techniquesmentioning

confidence: 99%

Tailor-made thermosets obtained by sequential dual-curing combining isocyanate-thiol and epoxy-thiol click reactions

Gamardella

Sabatini

Ramis

et al. 2019

Polymer

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In this work, a new family of thermosets based on thiol-isocyanate-epoxy networks has been prepared via sequential dual-curing methodology where both reactions are activated by temperature. The sequential dual behaviour of the new system proposed here is based on the faster reaction kinetic of the first curing stage, i.e. the isocyanate-thiol coupling, which proceeds at a relatively low temperature, compared to the second stage, i.e. the epoxy-thiol reaction, between the remaining thiol functionalities and the epoxy groups that takes place at a higher temperature. Furthermore, the effect of using different aliphatic isocyanates was investigated. Both reactions have a click character and the intermediate/final materials show a wide range of properties depending on the relative contribution of both curing stages thanks to the selected ratio between the isocyanate and epoxy groups. The new thermosets obtained were characterized from the thermal and dynamic mechanical point of view, resulting excellent candidates as smart materials due to their narrow transitions, which favours fast and controlled changes in their macromolecular features.

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Reaction Kinetics of Polyurethane Formation Using a Commercial Oligomeric Diisocyanate Resin Studied by Calorimetric and Rheological Methods

Cited by 21 publications

References 49 publications

Reaction modeling of urethane polyols using fraction primary secondary and hindered‐secondary hydroxyl content

Reaction modeling of urethane polyols using fraction primary secondary and hindered‐secondary hydroxyl content

A thermal and rheological investigation during the complex cure of a two‐component thermoset polyurethane

Tailor-made thermosets obtained by sequential dual-curing combining isocyanate-thiol and epoxy-thiol click reactions

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