The Bonding Mechanism of the Micro-Interface of Polymer Coated Steel

Polymers

Jiyang Liu¹  Qingdong Zhang¹  Boyang Zhang¹  Mingyang Yu¹ 

[1] School of Mechanical Engineering, University of Science and Technology, Beijing 100083, China;

关键词: polymer coated steel;    micro-interface;    bonding mechanism;    molecular dynamics (MD);    quantum mechanics (QM);   

DOI  :  10.3390/polym12123052

来源: DOAJ

【 摘 要 】

As food and beverages require more and more green and safe packaging products, the emergence of polymer coated steel (PCS) has been promoted. PCS is a layered composite strip made of metal and polymer. To probe the bonding mechanism of PCS micro-interface, the substrate tin-free steel (TFS) was physically characterized by SEM and XPS, and cladding polyethylene terephthalate (PET) was simulated by first-principles methods of quantum mechanics (QM). We used COMPASS force field for molecular dynamics (MD) simulation. XPS pointed out that the element composition of TFS surface coating is Cr(OH)₃, Cr₂O₃ and CrO₃. The calculation results of MD and QM indicate that the chromium oxide and PET molecules compound in the form of acid-base interaction. The binding energies of Cr₂O₃ (110), (200), and (211) with PET molecules are −13.07 eV, −2.74 eV, and −2.37 eV, respectively. We established a Cr₂O₃ (200) model with different hydroxyl concentrations. It is proposed that the oxygen atom in C=O in the PET molecule combines with –OH on the surface of TFS to form a hydrogen bond. The binding energy of the PCS interface increases with the increase of the surface hydroxyl concentration of the TFS. It provides theoretical guidance and reference significance for the research on the bonding mechanism of PCS.

【 授权许可】

Unknown