Phenol replaced by Lignin

For the first time, panels for high-quality interior applications are on the market where 50 percent phenol has been replaced by the natural adhesive lignin. This is the result of an eight-year collaboration between Wageningen Food & Biobased Research and NEMHO, the R&D department of the Dutch producer Trespa International B.V., the Italian sister company Arpa Industriale and other materials technology companies of Broadview Holding.

Arpa HPL and FENIX NTM panels are made of paper and thermosetting resins based on phenol. The thermal pressure creates a durable structure that makes the material suitable for interior applications. Phenol  has been used in these thermosetting resins for years. However, that substance is on the EU list of substances of very high concern. NEMHO and Wageningen Food & Biobased Research are working together on the development of an alternative resin based on lignin technology. The natural adhesive lignin is found in woody crops and is abundant in nature.

According to WUR, the new production process makes optimal use of the intrinsic binding properties of lignin. To ensure that lignin can be used on a large scale, it was decided to use lignin that is released as a by-stream in the kraft process, the most important pulp process for the production of cellulose for paper. In this process, wood is processed into wood pulp. Subsequently, it was investigated how the lignin behaves during the synthesis of the lignin-based resin and during the gluing process. The researchers found that lignin cannot simply be applied, but that adjustments are needed. After eight years of research, the breakthrough came, in which 50 percent phenol could be replaced.

The parties involved aim to  eventually be able to completely replace phenol in the thermosetting resin with lignin.

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