| 초록 |
Polymers undergo various types of mechanical deformations during processing to be utilized for their desired purpose, thus it is crucial to understand their rheological properties. Most of the shear rheological properties such as viscosity, G’ and G’’ are well characterized for various polymers, however, it is difficult to elucidate the response of them under extensional deformation which mainly occurs in extrusion, fiber spinning, or foaming. Furthermore, the extensional rheological properties of polymers can vary greatly depending on their shape or conformation as their degree of entanglement and chain extensibility change. In this research, the extensional flow behavior of long-chain multi-arm polymer melts is characterized by the dripping-onto-substrate method, and it is also confirmed how the physical properties of the linear polymer can be changed according to the number and length of arms and the degree of blending. |
