Revealing the influence of steric bulk on the triplet-triplet annihilation upconversion performance of conjugated polymers.

A series of poly(phenylene-vinylene)-based copolymers are synthesized using the Gilch method incorporating monomers with sterically bulky sidechains. The photochemical upconversion performance of these polymers as emitters are investigated using a palladium tetraphenyltetrabenzoporphyrin triplet sensitizer and MEH-PPV as reference. Increased incorporation of sterically bulky monomers leads to a reduction in the upconversion efficiency despite improved photoluminescence quantum yield.

RAFT polymer cross-coupling with boronic acids.

The ability to modify the thiocarbonylthio end-groups of RAFT polymers is important for applications where an inert or highly functionalised material is required. Here we report a copper promoted cross-coupling reaction between RAFT polymer end-groups and aryl boronic acids. This method gives high conversion to the modified polymers, and is compatible with a wide variety of functional molecules.