Copolymerization induced emission of poly[(methylenelactide)-co-(2-vinylpyridine)]

Copolymerization is a facile and effective approach to develop functional polymers from two or more types of monomers. In the present work, we report an unexpected photoluminescence (PL) of poly[(methylenelactide)-co-(2-vinylpyridine)] (PLVPs) random copolymers, which possess intense blue emission in dilute solution with a quantum yield higher than 20%. Also, the PL of PLVPs exhibits the concentration quenching feature. Such intrinsic PL of PLVPs is attributed to the intra-chain and inter-chain interactions of pyridine and lactone rings. The dependence of emission on the molecular weights and monomer ratios of PLVPs, as well as excitation wavelength, in both solution and solid states was investigated. This work provides new insight into the design and preparation of luminescent polymers.