Cardanol (3-pentadecenyl-phenol), a well-known non-edible natural oil obtained as a by-product of the Cashew Industry, represents a valid alternative to petro-based derivatives, thanks to its peculiar chemical structure. When used as polymer building block in the synthesis of epoxy curing agents or polyols and diols for polyurethane applications, cardanol can impart unique benefits, like chemical resistance, hydrolytic stability, thermal resistance and balanced mechanical properties. This work will present one of the most recent applications of cardanol in the field of polyurethane chemistry, highlighting its role as suitable isocyanate protective group. In fact, once used in polyurethane prepolymers, it demonstrates various benefits including favorable and easily tunable deblocking conditions, lower viscosity of resulting NCO-blocked prepolymers and excellent storage stability in comparison to commonly used phenolic compounds (phenol, nonylphenol, in particular). At the same time, incorporation of functional groups on the aromatic ring (e.g. electron withdrawing groups) or the chemical conversion of 3-pentadecenyl-phenol into fully cyclo-aliphatic derivatives (e.g. cyclohexanol, oxime, lactam-types) further extend the application range, allowing the development of innovative cardanol-derived isocyanate protective groups characterized by unique chemical features. When adopted at industrial level, Cardanol and its functionalized derivatives offer polyurethane Formulators versatile, bio-derived tools suitable for a wide range of applications, substrates (plastic, metal,…) and processing conditions.

Novel bio-based blocking agents derived from cashew nut shell liquid for polyurethane applications

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.