Synopsis

In recent years, general sustainability awareness, legislation and consequently also customer requirements are dictating trends in industrial development, and the relatively conservative coating segment being no exception.

Alkyds as representatives of intrinsic-bio-based-derived polymers are still strongly present in many coating segments but they possess some intrinsic drawbacks. In the last decades, high-performance coatings are being produced from petrol-based raw materials, offering significant improvements in substrate protection and its prolonged durability while maintaining visual, protective and other special properties.

For a long time, water-based coatings were limited to less demanding applications, such as do-it-yourself (DIY) paints. After entering the new millennia, (European) legislation pushed industrial coating producers to reduce volatile organic compounds (VOCs) due to impacts on human health and air pollution.

Many potential replacements of fossil-based building blocks are being increasingly investigated lately. Efforts are focused on new or improved bio-based monomers for polymer (resin) synthesis. The simplest case is the so-called drop-in approach where a fossil-based substance is replaced by an identical one derived from biomass. Bio-based carbon can be validated either by ¹⁴C or via bio-mass-balance (BMB) certification. Additionally, many alternative bio-substances have been used and evaluated in various coatings systems. Besides performance, cost-performance ratio must also be considered.

Increasing bio-based carbon is the first and most important step. However, accurate Life Cycle Assessment (LCA) is needed to claim sustainable resins and coatings.