Novel, protein-based binder system to manufacture dispersion paints using the “1 bucket concept” under development

Over the past few decades, extensive knowledge regarding water-based paints has been amassed with a view to reducing their VOC content and, at the same time, improving their environmental compatibility. However, calls for more environmentally friendly paint systems are growing ever louder – from consumers and industry alike.

Interior and exterior wall paints are produced from a complex mixture, comprising mainly polymer binders, pigments, fillers, additives and water (the solvent). The binders in this mixture are the film formers in the coating systems. They account for up to 30% of the total mixture and therefore influence important properties, such as adhesive capacity, resistance to cracking and flaking, and the processing properties of the wall paint. Nowadays, commercial binders are made primarily from polymers or copolymers of styrene, butadiene, various acrylates and vinyl acetate – all of which are synthesized from fossil raw materials. Various research approaches have been pursued to replace these petroleum-based binders with more sustainable options, without compromising the qualitative and performance properties of the dispersion paint. However, little progress has been made – until now.

The “DisPro” project aims to provide the market with more sustainable alternatives by swapping petrochemical polymers in aqueous dispersion paints with plant-based raw materials.

Bio-based binder systems from plant-based raw materials

One possible bio-based alternative is to use biopolymers produced from renewable raw materials or residues as binders. This includes biopolymers from starch, protein or lignin.

Plant proteins have a broad range of different functional properties and, under certain conditions, these can produce foams or gels, for example. Moreover, their complex structure and modifiability make them potential candidates to act as binders and film formers, thereby replacing environmentally harmful acrylates. However, it has thus far not been possible to develop a consumer-friendly “1 bucket” solution that allows easy workability of a protein-based dispersion paint. Previous application solutions often require various components to be agitated and mixed immediately prior to use by the end consumer, which is a cumbersome, complex and error-prone process.

“DisPro” aims to develop a novel, protein-based binder for dispersion paints to help reduce the proportion of petroleum-based material components in the finished product. Commercially available plant-based raw materials will be used as the basis so that the results can be quickly transferred to industry applications.

Product development for subsequent industrial use

A toxicologically safe and sustainable binder system for application in ready-to-use, “1 bucket” dispersion paint will be developed in the “DisPro” project. The fully developed paint should have a long shelf life, good processing properties, a short drying time and a coating film with a high resistance to mechanical, chemical and biological interference. The binder should also be colorless and not impair the color effect of the actual pigment. Furthermore, it should be compatible with a wide variety of surfaces.