Thermo-oxidative aging of epoxy coating systems

Zahra, Yahya; Fayolle, Bruno; Kuntz, M.; Verdú, J.

doi:10.1016/j.porgcoat.2013.10.011

Cited by 40 publications

(27 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where A l is the absorbance, l the thickness of the film (expressed in cm), c the concentration (in mol l À1 ) and ε l the molar absorptivity at the considered wavenumber (in l mol À1 cm À1 ). Concentrations of oxidation products were thus assessed using molar absorptivity values equal to 500 l mol À1 cm À1 for carbonyls at 1765 cm À1 in PKHJ (estimated from phenyl acetate e see Appendix 1), 680 l mol À1 cm À1 for carboxylic acids at 1730 cm À1 in TGMDA-DDS [23] and 470 l mol À1 cm À1 for amides at 1675 cm À1 [10] (NB: the nature of the products will be justified later). Some comparisons were performed with the oxidation of TGMDA and DGEBA monomers.…”

Section: Characterizationmentioning

confidence: 99%

Thermal oxidation of aromatic epoxy-diamine networks

Delozanne

Desgardin

Cuvillier

et al. 2019

Polymer Degradation and Stability

View full text Add to dashboard Cite

The thermal oxidation of DGEBA-DDS (bisphenol A diglycidyl ether þ 4,4 0-diaminodiphenyl sulfone) and TGMDA-DDS (4,4 0-methylenebis(N,N-diglycidylaniline) þ 4,4 0-diaminodiphenyl sulfone) was performed at 80, 120, and 200 C and was monitored by FTIR. Oxidation was shown to generate amides and carbonyls. Comparisons were done with model systems displaying some common reactive groups, which highlighted the predominating role of methylene in a position of ether in DGEBA-DDS and methylene in a position of nitrogen hold by TGMDA in TGMDA-DDS. The participation of CH 2 in a position of DDS hardener group seems to depend on the temperature and decrease when lowering it. The oxidation of such complex systems must hence be described by a co-oxidation model where each kind of reactive sites is described by its own set of kinetic constants.

show abstract

Section: Characterizationmentioning

confidence: 99%

Thermal oxidation of aromatic epoxy-diamine networks

Delozanne

Desgardin

Cuvillier

et al. 2019

Polymer Degradation and Stability

View full text Add to dashboard Cite

show abstract

“…However, those phenomena were mainly evidenced in rigid epoxy/diamine systems where 2hydroxypropyl ether is possibly the only reactive site. The case of flexible epoxies (T g < 100 C) [18,19] was more scarcely studied so that we were interested in investigating:…”

Section: Introductionmentioning

confidence: 99%

Thermal-oxidation of epoxy/amine followed by glass transition temperature changes

Ernault

Richaud

Fayolle

2017

Polymer Degradation and Stability

View full text Add to dashboard Cite

Thermal oxidation of three epoxy resins differing by the nature of prepolymer (bisphenol A diglycidyl ether and 1,4-butanediol diglycidyl ether) and hardener (isophorone diamine and 4,7,10-Trioxa-1,13tridecanediamine) was studied by monitoring changes in glass transition temperature using DSC. Results were discussed using the DiMarzio's approach in which parameters are estimated from an additive group contribution. This theory allowed a fair assessment of T g values for unaged networks. During oxidation, epoxy networks were shown to undergo chain scissions occurring in great part in hydroxypropyl ether and isophorone groups. However, the exploitation of T g changes showed the coexistence and even the predominance of crosslinking in materials having linear aliphatic segments. The DiMarzio's approach was used to discuss the possibility of intramolecular cyclization or intermolecular crosslinks which were shown to predominate. Crosslinks were tentatively justified from a mechanistic point of view and quantified depending on experimental conditions.

show abstract

“…The formation of carbonyl group arises from the oxidization of the secondary alcohol groups in epoxy thermoset, 39 whereas that of amide group originates from oxidation of the a-amino carbon belonging to the chain segments. 40 As the temperature exceeds 500 8C, the typical absorption peaks at 1609, 1509, and 1460 cm 21 due to C@C stretching vibration in aromatic ring vanish, whereas a new broader peak at 1594 cm 21 shows up, manifesting the formation of polyaromatic structures. 41,42 In the case of EP/DAP10 and EP/AP10, it can be found that in the range of 25 to 500 8C, the spectra are similar to those of neat EP.…”

mentioning

confidence: 98%

Flame‐retardant properties and mechanisms of epoxy thermosets modified with two phosphorus‐containing phenolic amines

Wang

et al. 2016

J of Applied Polymer Sci

View full text Add to dashboard Cite

Two phosphorus-containing phenolic amines, a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based derivative (DAP) by covalently bonding DOPO and imine (SB) obtained from the condensation of p-phenylenediamine with salicylaldehyde, and its analog (AP) via the addition reaction between diethyl phosphite and SB, were used to prepare flame-retardant epoxy resins. The burning behaviors and dynamic mechanical properties of epoxy thermosets were studied by limited oxygen index (LOI) measurement, UL-94 test, and dynamic mechanical analysis. The flame-retardant mechanisms of modified thermosets were investigated by thermogravimetric analysis, Py-GC/MS, Fourier transform infrared, SEM, elemental analysis, and laser Raman spectroscopy. The results revealed that epoxy thermoset modified with DAP displayed the blowing-out effect during UL-94 test. With the incorporation of 10 wt % DAP, the modified thermoset showed an LOI value of 36.1% and V-0 rating in UL-94 test. The flame-retardant mechanism was ascribed to the quenching and diluting effect in the gas phase and the formation of phosphorus-rich char layers in the condensed phase. However, the thermoset modified with 10 wt % AP only showed an LOI value of 25.7% and no rating in UL-94 test, which was possibly ascribed to the mismatching of charring process with gas emission process during combustion. V C 2016Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43953.

show abstract

Thermo-oxidative aging of epoxy coating systems

Cited by 40 publications

References 27 publications

Thermal oxidation of aromatic epoxy-diamine networks

Thermal oxidation of aromatic epoxy-diamine networks

Thermal-oxidation of epoxy/amine followed by glass transition temperature changes

Flame‐retardant properties and mechanisms of epoxy thermosets modified with two phosphorus‐containing phenolic amines

Contact Info

Product

Resources

About