Acid Ionic Liquids as a New Hardener in Urea-Glyoxal Adhesive Resins - Université de Lorraine
Journal Articles Polymers Year : 2016

Acid Ionic Liquids as a New Hardener in Urea-Glyoxal Adhesive Resins

Abstract

The effect of acidic ionic liquid (IL) as a new catalyst on the properties of wood-based panels bonded with urea-glyoxal (UG) resins was investigated. Different levels of N-methyl-2-pyrrolidone hydrogen sulfate ([HNMP] HSO4 (0, 1, 2, 3 wt %)) were added to prepared UG resin. The resin was then used for preparing laboratory particleboard panels. Then, the properties of the prepared panels were evaluated. The structure of the prepared UG resin was studied by C-13 NMR, and thermal curing behavior of the resin before and after the addition of IL was measured by DSC. Additionally, the main oligomers formed in the UG reaction were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectroscopy. The results indicated that IL can be used as an efficient catalyst for UG resin. The physicochemical tests indicated that the addition of [HNMP] HSO4 from 0 to 3 wt % decreased the pH value of the glue-mix, and the pH decreased on curing to the same level as urea-formaldehyde resins. The gel accelerated with increasing catalyst content and with the decreasing of the pH in the UG resin. The panels prepared with IL had higher mechanical strength and dimensional stability compared to those made from UG resins containing NH4Cl. Scanning electron microscope (SEM) micrographs showed that the panels prepared with ionic liquid presented low porous. DSC analysis showed that the addition of IL to the UG resin decrease the energy of activation of the curing reaction to render possible cross-linking. The MALDI TOF results indicated a preponderant linearity of the oligomers formed, implying a high energy of activation of curing for UG resins.
Fichier principal
Vignette du fichier
polymers-08-00057.pdf (8.44 Mo) Télécharger le fichier
Origin Publisher files allowed on an open archive
Loading...

Dates and versions

hal-01599588 , version 1 (02-10-2017)

Identifiers

Cite

Hamed Younesi-Kordkheili, Antonio Pizzi. Acid Ionic Liquids as a New Hardener in Urea-Glyoxal Adhesive Resins. Polymers, 2016, 8 (3), pp.527 - 532. ⟨10.3390/polym8030057⟩. ⟨hal-01599588⟩
51 View
174 Download

Altmetric

Share

More