A Study on the Die Swell of Nylon 6 Melts

나일론6 용융물의 다이팽윤에 관한 연구

Rheological properties and die swell of nylon6 melts were measured by varying the shear rate, length/diameter of die, and temperature. Die swell was theoretically investigated on the concept of the recovery of strain and the rearrangement of velocity and compared with the experimental results. Die swell due to the recovery of strain was larger than that of rearrangement of velocity. Die swell increased with the shear modulus of nylon6 melts, and normal stress differences were evaluated from this relation. Die swell increased greatly in the range of lower shear rate but did not increased significantly in the higher shear rate.