Rosin-Containing Alkyd Resin Derivatives

As global petroleum reserves decline and petroleum-derived substances harm the environment, research into environmentally friendly and renewable resource applications has increased in recent years. Plant-based polymers and chemicals in particular are widely used due to their low cost and abundance.

Rosin is a hydrocarbon-rich pine tree resin with annual production of 1.2 million tons and is one of the abundant renewable chemicals. Rosin is a primary raw material for the ink, adhesive, pharmaceutical, varnish and gum industries [1-5]. Rosin differentiates positively from other renewable chemicals due to its chemical structure properties. When used together with other polymeric structures, its hydrocarbon-rich biomass provides a hydrophobic effect, while its hydrophenanthrene structure increases its thermal properties [3] (Figure 1).

Figure 1. Rosin resin and its chemical structure

Rosin resin typically consists of 90% resin and 10% neutral matter. Resin acid is isomeric with abietic acid. The remainder consists of dihydroabietic acid and dehydroabietic acid. Glycerin ester resin is obtained from rosin through esterification with glycerin [8].

Figure 2. Chemical structure of example rosin acids [3].

Rosin resin acids have been reacted with different monomeric structures to impart functional properties, and numerous biodegradable and biocompatible polymeric structures have been obtained. In the literature, incorporation of hydrophenanthrene structures into polymeric systems has yielded numerous physical and chemical properties provided by petroleum-derived aliphatic and aromatic structures [6-8]. In our company's R&D department, rosin resin acid was reacted within an alkyd containing soybean oil to exploit the properties provided by rosin, and the resulting alkyd was used to prepare paint to determine its effects. Paint prepared with rosin-based alkyd resin was found to have faster drying time, good adhesion properties, good UV resistance, high covering power, higher gloss and greater hardness compared to paint prepared from conventional alkyd resin. Our R&D department is actively continuing rosin-based alkyd resin project studies.   Dr. Cemil Dizman R&D Director İzel Kimya       Semiha Eral R&D Manager İzel Kimya  

References [1] Jifu Wang, Preparation and Characterization of rosin-based polymeric monomer, 2011. [2] Yao K., Degradable rosin-ester-caprolactone graft copolymers, 2011. [3] Kejian Yao, Renewable Bio-Based Polymers and Degradable Functional Polymers, 2013. [4] Yijun Zheng†, Well-Defined Renewable Polymers Derived from Gum Rosin, 2010. [5] Perry Wilbon, Novel Sustainable Polymers Derived from Renewable Rosin and Fatty Acids, 2015. [6] Olivars – Perez, A. Et al. Optical Materials, 27, 1825-1831, 2005. [7] Fuentes-Aud'en, C. et al. Fluid Phase Equilibria, 237,117-122,2005. [8] Louise McKeon B.Sc., Characterisation and determination of rosin compositions using analytical approaches, 2014.