Supramolecular self-assembly of tall oil rosin (TOR) abietic acid

Abstract

Byproducts from kraft pulping industries have been used as energy via burning for centuries. Recently the earth climate change and the growing awareness of harmful impact of burning byproducts has increased the demand for the transformation toward sustainability in the pulp and paper industries. Recently, lignin nanoparticles have gained significant attention and brought many innovative ideas. Abietic acid is the main component of tall oil rosin (TOR) that refined from black liquor. It is a tricyclic diterpene carboxylic acid with conjugated double bonds. It is a sustainable material with the potential to replace fossil-based materials in various industries, while safe for both people and environment. This work aims to investigate the potential of transform tall oil rosin into self-assembled nanoparticles. The tall oil rosin from crude tall oil was kindly supplied by partner company, Forcham. In this work, the structural properties of tall oil rosin were first studied, followed by an evaluation of its potential for nanoparticles production. The method was inspired by preparation techniques used for lignin nanoparticles, particularly solvent shifting and acid precipitation. Tall oil rosin was dissolved into an organic solvent or alkaline aqueous solution and then precipitated into nanoscale particles with a homogeneous dispersion. The obtained nanoparticles were characterized for size, zeta potential, morphology. Besides, the optimal condition for synthesizing self-assembled abietic acid nanoparticles were identified. As a result, abietic acid demonstrated itself as an excellent raw material for self-assembled nanoparticles synthesis. However, controlling the size distribution of the particles remains a challenge and will be the key focus for the future research.