Block copolymers have attracted much attention in recent years due to their unique self-assembly behavior that can be useful for the design and preparation of a diverse library of nanostructured materials1. Recent studies have demonstrated that the self-assembly process of the block copolymers can be controlled which can lead to novel optical properties2.
In this study, norbornene-based homopolymers and block copolymers containing macromolecular side chains such as polycaprolactone and polylactide were successfully synthesized by ring-opening metathesis polymerization of their corresponding macromolecular monomers using the third generation Grubbs’ initiator. Macromolecular monomers, such as norbornene-polycaprolactone and norbornene-polylactide, were prepared via Steglich esterification reaction catalyzed by dicyclohexylcarbodiimide and 4-dimethylaminopyridine. In general, block copolymers exhibit relatively low polydispersity index of around 1.1. In addition, the molecular weights of the polymers can be simply controlled by tuning the initial monomer to initiator ratio. The maximum reflectance wavelength of the block copolymer with high molecular weight (Mn = 872 kDa) is at 578 nm which is red-shifted by 160 nm compared to that of low molecular weight ones (Mn = 450 kDa). Binary blend of two block copolymers at varying weight percentages exhibit the maximum reflectance wavelength ranging from 418 nm to 578 nm. The optical and thermal properties of the binary blending system with different weight percentages are currently under investigation