| In the present work, polycaprolactam (PA6M2800) and two kinds of low density polyethylene ( LDPE1I30A, LDPE1I50A ) were selected to produce the PA6/LDPE blend fibers on the MiniLab II . The blend fibers were fabricated by melt mixing and direct spinning using maleic anhydride-grafted polyethylene (PE-g-MAH) as a reactive compatibilizer. The effect of melt viscosity ratio of blends, the content of compatibilizers, and cyclic mixing time on the morphology development of PA6 phase in LDPE matrix was investigated by means of capillary rheometer, scaning electron microscopy (SEM) and differential scaning calorimetry (DSC), respectively. According to the results of experiments in MiniLab II, the single screw spinning machine was used to investigate the effect of the drawing ratio, the content of compatibilizers, and static mixer on the properties of PA6 nanofibers.When the content of PE-g-MAH is 3 wt%, the PA6 component of mass ratio from 55 wt% to 65 wt% in PA6/LDPE blends formed a fine dispersed phase in the LDPE matrix. The diameter of PA6 superfine fiber stripped from PA6 / LDPE ( 1I30A ) blend fibers is thinner than that of PA6 / LDPE ( 1I50A ) blend fibers at the same condition. With the increase of compatibilizers and cyclic mixing time, the domain size of PA6 phase decreases first, and then increases slightly. The excessive compatibilizers and long cyclic mixing time result in the bad stripping performance. PA6 nanofibers with the diameter from 80 nm to 190nm were produced from the blend fiber with the mass ratio of PA6/LDPE/PE-g-MAH = 55/41.5/3.5 by controlling the cyclic mixing time with 16 minutes.PA6(M2800)/LDPE(1I30A) blends were melt-spinning on the single screw spinning machine. When the content of PE-g-MAH is 3.5 wt%, the PA6 superfine fibers with an average diameter below 180nm were obtained. For the PA6/LDPE blends without compatibilizers, the increase of the numbers of static mixer decreases the diameter of PA6 superfine fibers. However, for the PA6/LDPE blends with the PE-g-MAH content of 3.5 wt%, the stripping performance of blend fibers decreases and PA6 nanofibers conglutinate each other The diameter of PA6 fibers decreases and the crystallinity increases with increasing the drawing ratio of blend fibers. PA6 nanofibers with the diameter between 50 and 192 nm were produced from the blend fiber with the mass ratio of PA6/LDPE/PE-g-MAH = 55/41.5/3.5 by using a group of static mixer and controlling processing conditions. The above results suggest that it is possible to prepare nanofibers by incompatible blends under appropriate processing condition. |
