Polyurethane Foam Production Using Deep Eutectic Solvent Lignin as a Partial Polyol Substitute
Primary author: Dylan Cronin
Co-author(s): Xiao Zhang
Primary college/unit: Voiland College of Engineering and Architecture
Polyurethane is one of the world’s most important classes of industrial polymers due to its incredible versatility, ease of use in manufacturing, and low cost. This material is frequently used in the form of rigid and semi-rigid foams and represents a $70 bn/year market across the construction, transportation, furniture, and packaging industries. The current industry standard for polyurethane production is entirely dependent on petrochemical feedstocks for the supply of the two major components – polyol and isocyanate. This study investigated the substitution of up to 40 wt% of the polyol component of polyurethane foams with lignin. Preparing the material in this way both reduces the consumption of non-sustainable materials, and also allows for the potential incorporation of characteristics such as enhanced biodegradability and ultraviolet light stability.
This lignin was prepared using a novel, deep eutectic solvent (DES) procedure. This DES procedure is a mild, industrially scalable process, which yields a product of high purity, and more importantly of high structural homogeneity. The compatability of the lignin with traditional polyols was further improved via oxypropylation of the lignin structure, allowing for greater degrees of lignin substitution whilst maintaining an acceptable rigidity.
The goal of this work was to combine the societal need and commercial benefits of effectively utilizing forestry and agricultural wastes to produce bio-based materials and plastics from carbohydrates and lignin. Utilizing biomass wastes such as these not only helps to ensure the availability of a low-value and annually sustainable feedstock, but also provides new revenue streams for associated industries.