News

19-01-2023

Biorizon teams up with Kaneka to create hard bio-based coatings based on lignin and MS Polymer

Researchers from Biorizon co-initiator VITO and chemical company Kaneka Belgium joined forces to conduct research to create hard bio-based coatings based on lignin and MS Polymer™ with excellent adhesive properties. This research was published in the Polymers Paint Colour Journal (PPCJ).

Kaneka MS Polymer™ is a class of polymers having a long middle polyether section functionalised by silyl terminal groups. In the presence of moisture and a catalyst, MS polymer cure at room temperature into a rubbery product by hydrolysis and condensation of the reactive silyl groups. They are used in sealants, adhesives, or coatings with a variety of commercial applications in e.g., the building and construction, transportation, do-it-yourself, and flooring industry. MS Polymer-based sealants and adhesives have intrinsically good characteristics, such as adhesion on a wide range of substrates, flexibility, and ease of handling.

Moreover, in a recent study, it was shown that their thermal stability can strongly be improved by blending MS Polymer with bio-based, silylated lignin fragments. However, as the MS Polymer backbone is soft and rubbery, it is challenging to use them as base material for hard coatings. In the search for an alternative backbone to improve the properties of MS Polymer-based hard coatings, the use of bio-based materials is a prerequisite for Kaneka. Because of its hard, aromatic structure, lignin is an interesting base polymer for hard coating applications. Moreover, lignin is the second most abundant biopolymer on earth after cellulose, and available as a by-product of the pulping process of the paper industry.

It is therefore not a surprise that the utilisation of lignin as an alternative feedstock in value-added applications, such as bio-additives is attracting growing attention from both academia and industry. In this work, functionalised lignin fragments were used as base material for partly bio-based, hard coatings. They were combined with MS Polymer and other additives to optimise the performance.

This study showed the potential of lignin to be used as a base material for biobased hard coatings or primers. By functionalising lignin oligomers and dimers with reactive silyl groups, a moisture curing coating could be obtained. Addition of an MS Polymer reactive plasticiser and a low amount of silane resulted in a wellcrosslinked, chemically resistant system, showing a good adhesion to different substrates. Also, the adhesion of an MS Polymer-based sealant to the coating was excellent.

Contact

Do you possess a bio-refinery and are you looking for technologies to valorize lignin into valuable applications? Or are you a manufacturer of construction materials that wants to enhance functionalities? Then please contact Biorizon’s Lignin Horizon manager Karolien Vanbroekhoven at  karolien.vanbroekhoven@vito.be or +32 (0)4 93 51 42 70.

Source: Polymers Paint Colour Journal (PPCJ)