Anisotropic self-diffusion of fluorinated poly(methacrylate) in metal-organic frameworks assessed with molecular dynamics simulation
Tao Lu(鲁桃)1, Biao Xu(徐彪)1, Fei-Hong Ye(叶飞宏)1, Xin-Hui Zhou(周馨慧)3, Yun-Qing Lu(陆云清)1, Jin Wang(王瑾)1,2
1. School of Opto-Electronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China; 2. School of Telecommunication and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China; 3. Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing 210023, China
Abstract Utilizing the periodically structured metal-organic framework (MOF) as the reaction vessel is a promising technique to achieve the aligned polymer molecular chains, where the diffusion procedure of the polymer monomer inside MOF is one of the key mechanisms. To investigate the diffusion mechanism of fluorinated polymer monomers in MOFs, in this paper the molecular dynamics simulations combined with the density functional theory and the Monte Carlo method are used and the all-atom models of TFMA (trifluoroethyl methacrylate) monomer and two types of MOFs,[Zn2(BDC)2(TED)]n and[Zn2(BPDC)2(TED)]n, are established. The diffusion behaviors of TFMA monomer in these two MOFs are simulated and the main influencing factors are analyzed. The obtained results are as follows. First, the electrostatic interactions between TFMA monomers and MOFs cause the monomers to concentrate in the MOF channel, which slows down the monomer diffusion. Second, the anisotropic shape of the one-dimensional MOF channel leads to different diffusion speeds of monomers in different directions. Third, MOF with a larger pore diameter due to a longer organic ligand,[Zn2(BPDC)2(TED)]n in this paper, facilitates the diffusion of monomers in the MOF channel. Finally, as the number of monomers increases, the self-diffusion coefficient is reduced by the steric effect.
Effect of spatial heterogeneity on level of rejuvenation in Ni80P20 metallic glass Tzu-Chia Chen, Mahyuddin KM Nasution, Abdullah Hasan Jabbar, Sarah Jawad Shoja, Waluyo Adi Siswanto, Sigiet Haryo Pranoto, Dmitry Bokov, Rustem Magizov, Yasser Fakri Mustafa, A. Surendar, Rustem Zalilov, Alexandr Sviderskiy, Alla Vorobeva, Dmitry Vorobyev, and Ahmed Alkhayyat. Chin. Phys. B, 2022, 31(9): 096401.
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