Precise Polymer Design for the Development of New Materials (R-3273)

One of the most prominent synthesis strategies for conjugated polymer systems is the so-called Gilch or Gilch-type polymerization (GTP). In GTP, a monomer precursor is used that upon reaction with a strong base forms an active quinodimethane system that can undergo radical polymerization. For its radical mechanism, GTP is an attractive synthesis route since it allows for relatively mild reaction conditions and high tolerance towards functional groups. The aim of the proposed research program is to develop control methodologies that allows to synthesize poly(phenylvinylene)s or other poly(arylvinylene)s in a precise manner as known from controlled/living radical polymerization techniques in the realm of conventional radical polymerization (which techniques so far show, however, no effective control over GTP). At the present stage, no control mechanisms are known which leads to the synthesis of conjugated polymers with high dispersity, insufficient control over the average molecular weight and functionality. If a controlled GTP can be achieved, conjugated polymers with narrow molecular weight distribution, exactly pre-determinable molecular weight and high endgroup fidelity will become available. With such material at hand, block copolymers of various types become available, either in sequential or in modular design approaches. In this research a bottom-up approach is followed. First, the existing procedures are analyzed and a concise mechanistic and kinetic understanding of the polymerization is build up. With this knowledge at hand, a kinetic model is developed which can then be used to test control strategies and to predict the success rate of chosen synthesis routes. The most promising synthesis procedures are executed and tested via polymer characterization. After controlled GTP has become available, the method is used to synthesize different kinds of polymer architectures to provide new devices in the field of plastic electronics.

Keywords:CONJUGATED POLYMERS

Disciplines:Process engineering, Polymeric materials