Molecular dynamic simulation of core–shell structure: study of the interaction between modified surface of nano-SiO2 and PAMAA in vacuum and aqueous solution. Issue 9 (22nd November 2017)

• Record Type: Journal Article
• Authors: Dai, Shanshan; Liu, Yan; Zhang, Jinghan; Zhang, Tailiang; Huang, Zhiyu; Zhao, Xiaowen
• Is Part Of: Composite interfaces. Volume 24:Issue 9(2017)
• Page Start: 897
• Page End: 914
• Publication Date: 2017-11-22
• Subjects: Molecular dynamic simulation -- modification -- nanopaticle -- copolymer -- interaction; Composite materials -- Periodicals; 620.11805
• DOI: 10.1080/09276440.2017.1302398
• Languages: English
• ISSNs: 0927-6440

Abstract

Abstract: The interaction between acrylamide acrylicacid copolymer (PAMAA) and the modified surface of nano-SiO2 is investigated using the molecular dynamic (MD) simulation. The binding energies ( E binding ) of interface, the concentration profiles of PAMAA and functional groups (carboxyl and acylamino) of corresponding model, the mean square displacements (MSD) and diffusion coefficients ( D ) of PAMAA in four systems with different modifiers are all calculated at 325 K in vacuum. Vinyl trimethoxy silane (VTEOS) shows best modification effect in the systems mentioned above. Furthermore, the effects of temperature on the interaction between VTEOS modified surface of nano-SiO2 and PAMAA are studied at 300, 325, 350, 375 and 400 K in aqueous solution. Interesting results show that, water molecular layer reduces with the increase of temperature, and then improves the interaction between PAMAA and VTEOS modified surface of nano-SiO2 . The corresponding E binding of interface, the radial distribution functions (RDF) of carbon atoms on the surface and oxygen atoms of water molecules, the concentration profiles of PAMAA on the surface of nano-SiO2, the MSD and D of PAMAA are all studied seriously to find the reason of this counterintuitive phenomenon.