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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.

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The chemoenzymatic cascade synthesis of block copolymers combining enzymatic ring opening polymerization (eROP) and atom transfer radical polymerization (ATRP) is reviewed. Factors like reaction condition and initiator structure were investigated and optimized prior to the polymerization. The synthesis of block copolymers was successful in two consecutive steps, i.e. eROP followed by ATRP as evident from SEC and GPEC analysis. While in the one-pot approach, block copolymers could be obtained by sequential addition of the ATRP catalyst, side reactions were observed when all components were present from the start of the reaction. A successful one-pot synthesis was achieved by conducting the reaction in supercritical carbon dioxide

Oligo- and polysaccharides are important macromolecules in living systems, showing their multifunctional characteristics in the construction of cell walls, energy storage, cell recognition and their immune response. Starch, the most abundant storage reserve carbohydrate in plants, is composed of two types of alpha-glucan, amylose and amylopectin. The branched structure, high amount of functional groups, biocompatibility of starch architectures makes them suitable for applications in the biomedical field and in the food industry. The exact way of starch biosynthesis in plants is still not known today. Here we are using a tandem reaction of two enzymes to synthesize "artificial" starch or rather (hyper)branched amylose in vitro. One enzyme is responsible for building the linear (amylose) part while the other enzyme introduces the branches. With the described tandem reaction of two enzymes, we are currently synthesizing hybrid copolymeric materials bearing (hyper)branched polysaccharide structures. (C) 2008 American Chemical Society

The enantioselectivity of the Novozym® 435 catalysed ring-opening of lactones is related to the conformation of the ester: cisoid lactones show S-selectivity or no selectivity while transoid lactones show a pronounced R-selectivity. The inability of Novozym 435 to polymerise 6-MeCL stems from its opposing selectivities for the alcohol and acyl moiety. By combining Novozym 435 with a racemisation catalyst, unreactive terminal alcohols in the S-configuration can be turned into reactive terminal alcohols of the R-configuration which can propagate. Combining 2 different catalysts that work together to accomplish propagation, also referred to as iterative tandem catalysis, is an elegant approach to convert a racemic monomer quantitatively into a homochiral polymer.