H. Wynberg

Alternate donor-acceptor small-band-gap semiconducting polymers; Polysquaraines and polycroconaines

Abstract The idea that conjugated polymers with alternate donor and acceptor moieties in the main chain are characterized by a small band gap is proposed and explained. Experimental verification of this idea is reported in new classes of conjugated polymer semiconductors, polysquaraines and polycroconaines. These new materials show band gaps down to 0.5 eV, conductivities around 10−5 S/cm and are stable in air up 250°C or higher.

A new class of small band gap organic polymer conductors

SummaryPolysquaraines and polycroconaines have been synthesized. They form a new class of polymers with a small band gap, down to 0.5 eV. The small gap arises from the regular alternation of strong donor and acceptor-like moieties in a conjugated backbone.

Water-soluble polysquaraines and polycroconaines

Abstract The synthesis, characterization and several properties of water-soluble polysquaraine and polycroconaine are presented. The optical band gap of a film of the polycroconaine 4 amounts to 0.7 eV, equal to the photoconductivity band-gap.

Colourless nonlinear optical D-π-A polymers with sulphones as electron acceptors

Novel colourless side-chain methacrylate copolymers exhibiting relatively narrow charge-transfer bands at 335 nm and second-order optical nonlinearities up to d33= 4.3 pm V–1(at 1064 nm) have been synthesized and characterized.