Computer-Aided Design of Copolymers with Controlled Comonomer Distributions

The sequence distribution of comonomer units in copolymers drastically affects the properties of the polymeric materials; the prediction and control of the sequence distribution are challenging when there is a significant reactivity difference among the comonomers. In this study, we established a computer-aided design (CAD) framework to rationally design and synthesize copolymers with the desired comonomer distributions by using the scheduled comonomer addition strategy. We developed a simulation method that predicted the living copolymerization process with the scheduled addition of comonomers into the reaction mixture. The simulation quantitatively reproduced the real-world copolymerization results. The comonomer addition schedule was designed for a given target comonomer distribution with the aid of simulation; this process was then used to experimentally produce the copolymer. With this method, we successfully synthesized random copolymers via the ring-opening metathesis copolymerization of two norbornene derivatives with an approximately 25-fold difference in their propagation rate constant; this was impossible with a simple batch addition strategy. Copolymers with much more complicated comonomer distributions could also be designed. Our CAD framework will promote the development of a vast diversity of polymers with various properties, even from a limited set of monomers