Vigilancia Tecnológica

As a thermostable bio?filler for PUR adhesives, acidic or basic lignin was blended with aluminum hydroxide. The thermal resistance of the PUR adhesives was evaluated by measuring adhesion before and after heating. When the acidic or basic lignin content was greater than 15%, foaming is the preferred application of this system.AbstractFor the sustainability of the polyurethane resin (PUR) industry, petroleum?based materials must be replaced with renewable resource and economic aspects must be considered. Lignin is a renewable, thermostable biomass consisted with a phenolic polymer. As a thermostable bio?filler for PUR adhesives, acidic or basic lignin was blended with an amphiprotic inorganic filler, to reduce the resins and product costs due to cheap, unmodified materials. The thermal resistance of the PUR adhesives was evaluated by measuring adhesion before and after heating and with and without a mechanical effect caused by substrate penetration. The results show that after heating at 200°C, the PURs containing 7.5 or 15?wt% of dealkaline lignin or 7.5?wt% of alkaline lignin decomposed more slowly than the lignin?free PUR. The properties of the PURs were also analyzed using Fourier?transform infrared spectroscopy and differential scanning calorimetry. Additionally, the PURs containing over 30?wt% of dealkaline lignin show potential as environmentally friendly water?blown PUR foams.