| 학회 | 한국화학공학회 |
| 학술대회 | 2016년 봄 (04/27 ~ 04/29, 부산 BEXCO) |
| 권호 | 22권 1호, p.769 |
| 발표분야 | 이동현상 |
| 제목 | Mechanism of Interfacial Slip for Polymer Melts using Non-equilibrium Molecular Dynamics Simulation |
| 초록 | Understanding the behavior of interfacial slip is known to play a key role in practical polymer processing, lubrication etc. However, it is challenging to fully understand molecular mechanism of slip. Here, we elucidate the molecular mechanism and dynamics of slip in confined unentangled and entangled linear polyethylene (PE) melts under shear flow. Our results identify three distinctive regimes with regard to the degree of slip (d s ), and reveal the underlying molecular mechanisms. In the weak flow regime, interfacial polymer chains perform the z-to-x rotation in the vorticity plane, which diminishes the wall friction along the flow direction, leading to an increase in d s . In the intermediate flow regime, the repetitive chain detachment-attachment (out-of-plane wagging) mechanism is found through competition between the flow field and wall interaction, resulting in a constant value of ds for unentangled melts. For entangled melts, d s decreases with increasing shear rate due to an additional disentanglement mechanism between interfacial and bulk chains. In the strong flow regime, d s increases again for all systems. This regime is characterized by chaotic chain rotation and tumbling due to collisions between interfacial chains and the wall. |
| 저자 | 정소담 , 조수원 , 김준모 , 백충기 |
| 소속 | UNIST |
| 키워드 | 이동현상 ; 유체역학 ; 유변학 |
| VOD | VOD 보기 |
| 원문파일 | 초록 보기 |
