Author: Nicole Beiser

Sustainable access to biobased biphenol epoxy resins by electrochemical dehydrogenative dimerization of eugenol

Limited fossil resources require innovative monomers and polymers derived from renewable feedstocks such as plant biomass. Thermosetting epoxy resins largely rely on petrochemical bisphenol-type monomers, which give high performance materials but are controversial due to their effects on human health. Herein, we present two biobased epoxy resins by direct dehydrogenative dimerization of eugenol, the main component of clove oil. Taking the Principles of Green Chemistry into account, we developed electrochemical dehydrodimerization at reticulated vitreous carbon (RVC) electrodes using methanol as environmentally benign solvent. Thus, fluorinated solvents such as 1,1,1,3,3,3-hexafluoroisopropa…

research product

Biobased Epoxy Resin by Electrochemical Modification of Tall Oil Fatty Acids

A biobased epoxy resin was prepared from tall oil fatty acids (TOFAs), a byproduct of the pulping industry. As free carboxylic acids compromise resin stability, TOFA was subjected to non-Kolbe decarboxylation to give alkenes upon loss of CO2. Thereby, the degree of unsaturation is significantly increased. This electrosynthetic protocol using an undivided cell setup and inexpensive graphite electrodes in a galvanostatic operation mode was scaled to a 1.5 L reactor, making use of electric current as a green and waste-free reagent. Simple, cost-efficient epoxidation using oxone subsequently gives an epoxy resin of low viscosity. Curing with anhydrides yields thermoset materials. Dynamic mechan…

research product

Adsorption and separation of black liquor-derived phenol derivatives using anion exchange resins

Abstract Kraft black liquor is the major waste stream of the paper pulping industry. This stream is usually directly incinerated in such facilities for energy production and recycling of the inorganic chemicals involved. However, lignin and other low molecular organic fragments dissolved in black liquor give rise to a large variety of aromatic fine chemicals. Energetic use of black liquor and its components prevents the removal of these valuable compounds from the waste stream. We present an easy protocol for adsorption and selective desorption of low molecular phenol derivatives from black liquor depending on the composition of the desorption system. Furthermore, adsorption experiments in …

research product

Investigations on isomerization and rearrangement of polycyclic arenes under oxidative conditions – Anodic versus reagent-mediated reactions

Abstract Electro-organic conversions at an active molybdenum anode enable the formation of fused arenes. High chemoselectivity was achieved under anodic conditions, and a reagent-induced selectivity was observed by comparison with results of MoCl5-mediated reactions. Polycyclic arenes like phenanthrenes, triphenylenes, chrysenes, or helicenes were selectively obtained in yields up to 87% and in some cases unusual rearrangements were crucial for the product formation.

research product