This work addresses the short-term thermal stability of suspension poly(vinyl chloride) (PVC) films formulated with phosphonium ionic liquids, PhILs (trihexyl(tetradecyl)phosphonium dicyanamide, [ P 1 4 , 6 , 6 , 6 ] [ d c a ] ; t r i h e x y l ( t e t r a d e c y l ) p h o s p h o n i u m b i s -(trifluoromethylsulfonyl)imide, [P 14,6,6,6 ][Tf 2 N]; tetrabutyl phosphonium chloride, [P 4,4,4,4 ][Cl]) and their mixtures with a conventional plasticizer (diisononyl phthalate, DINP). Kinetic parameters for the dehydrochlorination step were determined using a well-accepted isoconversional (multiheating-rate) approach. Results show that PVC films formulated with PhILs, and their mixtures with DINP, present lower thermal stability than those formulated only with DINP, and in spite of PhILs' higher intrinsic thermal stability. Nevertheless, PVC films formulated with [P 14,6,6,6 ][Tf 2 N] present the highest long-term thermal stability. Calculated kinetic parameters provide quite good predictions of the thermally stimulated decomposition of most of the targeted formulations. These results are expected to assist on the identification of potential applications of PhILs in the life cycle assessment of PVC-based materials, either as plasticizers/thermal stabilizers or as catalysts for PVC waste recycling processes.

Wood-based products usually have serious limitations concerning contact with water, both because wood is a hygroscopic material and because the commonly used binder has low moisture resistance. This paper studies the effect of panel moisture content (MC) on the physico-mechanical properties of medium density fiberboards (MDF). Several commercial MDF boards produced in Europe were stored at room temperature and relative humidity (RH) for 9 weeks (approx. range 15–20 °C and 50–85% RH). Every week, a strip of each MDF board was cut out, divided into 5 × 5 cm test pieces and its internal bond strength (IB) was measured. A strong influence of MDF moisture content on internal bond strength was observed and therefore IB test pieces were stored in a climatic chamber (either at 20 °C, 55% RH and at 20 °C, 70% RH). A decreasing linear relation was established between IB and MC. It was found that this effect is reversible: after drying, internal bond strength rises again (following a slight hysteresis). This work reinforces the importance of conditioned storage before board properties analysis, as described in European Standard EN 319.

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