Selective dispersion of neutral nanoplates and the interfacial structure of copolymers based on coarse-grained molecular dynamics simulations

Abstract

The selective dispersion of neutral nanoplates (NNP) and the control of the interfacial structure of copolymers are challenging. In this work, we employ coarse-grained molecular dynamics (CGMD) to investigate the dispersion of NNP and the interfacial structure. The introduction of NNP significantly changes the interfacial structure and formation mechanism of diblock copolymers (DBCP), which is related to the matrix phase, distribution, composition, and length of two different chain segments (A and B) in A_mB_n-DBCP. The phase-weak groups that have a poor interaction with NNP will stack easily, whereas the stacking degree for the phase-rich groups that have a strong interaction with NNP decreases due to the addition of NNP. The interaction between two phases will be enhanced, which is favorable for the formation of a random network structure. Due to the strong interaction of the phase-rich groups with NNP, the NNP change the accumulation types of phase-weak groups and enhances the combination of two chain segments in favor of the formation of a cylindrical micelle-like structure. The transmission electron microscopy (TEM) images show that layered double hydroxide (LDH) orientationally distributes in the acrylic acid chain segments in ethylene acrylic acid (EAA) random copolymers, which is in agreement with the theoretical simulation results. This proves that the selective dispersion of LDH in copolymers affects their interfacial structure.