Analysis of curing reaction of liquid-crystalline epoxy compositions by using temperature-modulated DSC TOPEM®

Journal of Thermal Analysis and Calorimetry - The curing behaviour of the composition of a liquid-crystalline diepoxy monomer (LCEM) with the central triaromatic mesogenic group was studied using...     

Preparation of hydrophobic tannins‐inspired polymer materials via low‐ppm ATRP methods

The novel hydrophobic coating material was received for the first time by a two‐step synthetic route. Firstly, the 15‐functional brominated macroinitiator was prepared by the esterification methodology. Next step covers synthesis of star‐like polymers by poly(n‐butyl acrylate) (PBA) arms polymerization via three low‐ppm atom transfer radical polymerization (ATRP) approaches including application of copper and silver wire in SARA and ARGET ATRP, respectively, as driving forces in redox cycle of catalyst, and an external stimulus in the form of electric current (seATRP) as the third approach in copper(II) regeneration system. As expected, the electrochemically mediated technique allows synthesis of tannic acid‐inspired coating polymers in precisely controlled manner during the entire polymerization process, proved by linear first‐order kinetics plot in contrast to above‐mentioned methods, low dispersity (Ð = 1.18) of star‐shaped polymers, and high efficiency of initiation (? _i = 81%) determined after detaching of polymers side arms. Macromolecules received by all low‐ppm ATRP solutions were characterized by preserved chain‐end functionality (theoretical dead chain fraction; DCF_theo <1%). Adhesive and hydrophobic properties of received polymer materials were investigated by contact angles (θ) and free surface energy (FSE) calculations. Prepared polymer films besides excellent hydrophobic properties have great potential as a self‐healing solution.