Kinetic and thermodynamic studies of the formation of a polyurethane based on 1,6-hexamethylene diisocyanate and poly(carbonate-co-ester)diol

d’Arlas, Borja Fernández; Rueda, Lorena; Stefani, Pablo Marcelo; Caba, Koro de la; Mondragón, Iñaki; Eceiza, Arantxa

doi:10.1016/j.tca.2007.03.021

Cited by 90 publications

(60 citation statements)

References 56 publications

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“…In [18], Fernandez d'Arlas et al applies so-called isoconversional methods to describe the curing process of a HDI-based polyurethane under isothermal conditions. The differential method by Friedman [19] and the approaches of Flynn-Wall-Ozawa [20] and Kissinger-Akahira-Sunose [21] are used and compared to the model-based autocatalytic approach by Kamal-Sourour [22].…”

Section: Introductionmentioning

confidence: 99%

“…The differential method by Friedman [19] and the approaches of Flynn-Wall-Ozawa [20] and Kissinger-Akahira-Sunose [21] are used and compared to the model-based autocatalytic approach by Kamal-Sourour [22]. In the context of this work, the investigations of Fernandez d'Arlas et al [18] are extended by the description of non-isothermal curing processes using a method described in [23] by Vyazovkin and applied to an MDI-based polyurethane.…”

Section: Introductionmentioning

confidence: 99%

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Kinetic Prediction of Fast Curing Polyurethane Resins by Model-Free Isoconversional Methods

Stanko

Stommel

2018

Polymers

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Abstract:In this work, the characterisation of reaction kinetics of a methylene diphenyl diisocyanate (MDI)-based fast curing polyurethane resin (PUR) and the mathematical description of its curing process are presented. For the modelling of the reaction process isoconversional methods, which are also called model-free approaches, are used instead of model-based approaches. One of the main challenges is the characterisation of a reactive system with a short pot life, which already starts to crosslink below room temperature. The main focus is the evaluation of the applicability of isoconversional methods for predicting the reaction kinetics of fast curing polyurethane resins. In order to realise this, a repeatable methodology for the determination of time-and temperature-dependent reaction curves using differential scanning calorimetry (DSC) is defined. The cure models defined by this method serve as the basis for process simulations of PUR processing technologies such as resin transfer moulding (RTM) or reactive injection moulding (RIM) and reactive extrusion (REX). The characterisation of the reaction kinetics using DSC measurements is carried out under isothermal and non-isothermal conditions. Within this work isoconversional methods have been applied successfully to experimentally determined DSC data sets. It is shown that the reaction kinetics of fast curing polyurethane resins can be predicted using this methods. Furthermore, it is demonstrated that the time-dependent change of conversion of the considered polyurethane under isothermal curing conditions can also be predicted using isoconversional methods based on non-isothermal DSC measurements. This results in a significant reduction in the experimental effort required to characterise and model the curing process of polyurethanes.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Kinetic Prediction of Fast Curing Polyurethane Resins by Model-Free Isoconversional Methods

Stanko

Stommel

2018

Polymers

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“…The coordination-insertion mechanism of the ROP reaction was characterized from the 1 H-NMR spectra of PCL samples with low molecular weights and therefore high end-group concentrations. To obtain the activation energy of the ROP reaction, isoconversional analysis [27,28] based on the Friedman, KissingerAkahira-Sunose and Ozawa-Flynn-Wall methods was applied to non-isothermal DSC data. From the results obtained, Scheme 1 Coordination-insertion mechanism of ε-CL polymerization …”

Section: Introductionmentioning

confidence: 99%

Isoconversional kinetic analysis of ring-opening polymerization of ε-caprolactone: Steric influence of titanium(IV) alkoxides as initiators

et al. 2012

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Four titanium(IV) alkoxides, namely: Ti(IV) npropoxide (1), Ti(IV) n-butoxide (2), Ti(IV) tert-butoxide (3), and Ti(IV) 2-ethylhexoxide (4), have been used as initiators in the bulk ring-opening polymerization (ROP) of ε-caprolactone (ε-CL). The influence of the alkoxide group on the course of the ROP of ε-CL was investigated by means of 1 H-NMR and differential scanning calorimetry (DSC). The 1 H-NMR spectra confirmed that the ROP reaction of ε-CL proceeded via the widely accepted coordinationinsertion mechanism for each of the four initiators. Isoconversional methods have been used to evaluate non-isothermal DSC data via the equations of Friedman, Kissinger-AkahiraSunose (KAS) and Ozawa-Flynn-Wall (OFW). The kinetic studies showed that the polymerization rate for the four initiators (1-4) was in the order of 1>2≈4>3. The lowest activation energies (40-47, 42-44, and 49-52 kJ/mol for the Friedman, KAS and OFW methods respectively) were found in the polymerizations using Ti(IV) n-propoxide (1), while the highest activation energies (84-107, 77-87, and 80-91 kJ/mol for the Friedman, KAS and OFW methods respectively) were obtained using Ti(IV) tert-butoxide (3). Differences in the rates of polymerization and the activation energies amongst the four initiators appeared to be governed mainly by the different degrees of steric hindrance in the initiator structure. These results represent important findings regarding the steric influence of the alkoxide groups on the kinetics of the ROP of ε-CL initiated by titanium(IV) alkoxides.

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“…This work is complemented by two previous papers in which the kinetics of reaction (16) and phase separation and properties as a function of hard segment chemistry (17) were analyzed for these segmented novel polyurethanes. Fourier transformed infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and atomic force microscopy (AFM) techniques are used for the analysis and comparison of these two sets of materials nano/micro-structure.…”

Section: Introductionmentioning

confidence: 99%

Inverting Polyurethanes Synthesis: Effects on Nano/Micro-Structure and Mechanical Properties

et al. 2010

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Two sets of new thermoplastic elastomeric polyurethanes were prepared by different routes. One route was the common two shoot polymerization, in which a short diol is added at the last step in order to link prepolymer chains. The new rout that is described here consisted in preparing firstly the hard segments upon 1,6-hexamethylene diisocyanate (HDI) and 1,4-butanediol (BD), used in the previous case as chain extender, and adding finally the polydiol in the second step, in a chain extender fashion, in order to form the grown polyurethane. The differences between these two sets of materials were considerable due to the more ordered and crystalline hard segments formed and the subsequent nano-domain distribution that aroused when inverting the common synthesis. Inter-domain distances and domains sizes are measured and also compared with those of the literature. The structure/properties relationships of synthesized polyurethanes with different hard segment content were analyzed by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), atomic force microscopy (AFM), and performing tensile and Shore D hardness tests.

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Kinetic and thermodynamic studies of the formation of a polyurethane based on 1,6-hexamethylene diisocyanate and poly(carbonate-co-ester)diol

Cited by 90 publications

References 56 publications

Kinetic Prediction of Fast Curing Polyurethane Resins by Model-Free Isoconversional Methods

Kinetic Prediction of Fast Curing Polyurethane Resins by Model-Free Isoconversional Methods

Isoconversional kinetic analysis of ring-opening polymerization of ε-caprolactone: Steric influence of titanium(IV) alkoxides as initiators

Inverting Polyurethanes Synthesis: Effects on Nano/Micro-Structure and Mechanical Properties

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