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The attention towards the utilization of sustainable feedstocks for polymer synthesis has grown exponentially in recent years. One of the spotlighted monomers derived from renewable resources is 2,5-furandicarboxylic acid (FDCA), one of the most promising bio-based monomers, due to its resemblance to petroleum-based terephthalic acid. Very interesting synthetic routes using this monomer have been reported in the last two decades. Combining the use of bio-based monomers and non-toxic chemicals via enzymatic polymerizations can lead to a robust and favorable approach towards a greener technology of bio-based polymer production. In this chapter, a brief introduction to FDCA-based monomers and enzymatic polymerizations is given, particularly focusing on furan-based polymers and their polymerization. In addition, an outline of the recent developments in the field of enzymatic polymerizations is discussed.

Because of current interest in reducing the toxicity of formaldehyde resins and increasing the use of agro-based renewable materials, plant proteins are being studied as eco-friendly wood adhesives. Commercial wood adhesives based on soy proteins are now available. In our laboratories, we are using cottonseed protein as an alternative to soy protein in wood adhesive application. In this presentation, a review (and update) will be given on our cottonseed protein adhesives work. Thus, cottonseed protein isolate (CPI) was shown to exhibit equivalent (or better) dry adhesive strength and superior hot water resistance relative to soy protein isolate (SPI). In addition, we evaluated a large number of additives to further improve the proteinu2019s adhesive performance. Low-molecular-weight carboxylic acids were shown to be adhesion promoters that enhanced the dry adhesive strength of CPI. Another group of promoters consisted of phosphorus-containing acids that improved both the dry adhesive strength and the hot water resistance of CPI. A third group of promoters comprised selected anionic polysaccharides that enhanced both the dry and hot water adhesive performance of CPI. These promoters worked well with CPI but showed only negligible effects on SPI. Cottonseed protein is known to contain more arginine (11u201312%) than does soy protein (7u20138%). As arginine carries a net cationic charge at most pH values (up to 12.0), the preferred enhancement of the promoters on CPI (relative to SPI) may be due to the interactions of proteinu2019s cationic charges with the anionic charges on the promoters. The enhanced adhesive performance of the CPI-promoter combinations should make cottonseed protein an attractive ingredient in adhesive formulations.