[SY-H6] Symposium H-6

[SY-H6] A molecular dynamics study of dissolution of covalent adaptable networks in organic solvent

^○Yaguang Sun¹, Hua Yang², Yafang Guo¹ (1.Dept. of Mechanics, Beijing Jiaotong Univ., China, 2.State Key Lab. for Geomechanics and Deep Underground Engineering, China Univ. of Mining and Tech., China)

Thermosets have outstanding mechanical strength and solvent resistance due to their permanently cross-linked networks. They cannot flow upon heating and cannot be reshaped and recycled. The recently developed reversible networks provide opportunities to recycle thermoset polymers. For example, the covalent adaptable networks (CANs; also known as vitrimers) can rearrange their network topology through reversible bond exchange reactions (BERs). It was recently reported that CANs can be dissolved in solvents. At high temperature, small solvent molecules can break long polymer chains into short segments via BERs. In this study, molecular dynamics simulations are used to investigate the dissolution of an epoxy CAN in alcohol solvents due to the transesterification type BER. The diffusion of solvent molecules and the decomposition of epoxy networks are analyzed. It is found that the dissolution proceeds in a surface erosion mode, which is consistent with experimental observations.