Potential of Organosolv Lignin Based Materials in Pressure Sensitive Adhesive Applications

Blending lignin with other polymers has long been utilized as a potent approach to explore novel applications for lignin. Yet, combinations of organosolv lignin (OSL) with superplasticizer have been hardly explored as a potential to design novel material properties. In this study, a commercial superplasticizer, a polycarboxylate polyether (PCE) is blended with a beech-based organosolv lignin, and their miscibility and adhesive properties are studied over the entire compositional range. All blend compositions exhibit a single glass transition temperature (T-g) that follows the Kwei model of miscible polymer blends, while a thermal stabilization effect is evidenced in blends containing up to 50% lignin. Fourier transform infrared spectroscopy (FTIR) investigations reveal specific interactions between functional groups in PCE and lignin OH groups as molecular basis for miscibility. The rheological properties, tackiness, and adhesive peel strength suggest that these blends have potential as a base formulation for pressure sensitive adhesive applications, albeit needing some fine-tuning.