Papers by Author: Run Jun Sun

Abstract: In this work, the crimp properties of PTT/PET bicomponent filament with different component ratios were investigated. The results show that, after boiling water treatment for 15 minutes, the crimpability of 50/50 component ratio is superior to that of 40/60 and 60/40 component ratio. Heat treatment can realize the shrinkage difference of the two components in a biocomponent filament and enable the biocomponent filament to have good crimpability and bulkiness. In addition, different heat treatments, heat treatment time and heat treatment temperature can also bring different crimp effects to the biocomponent filaments.

Abstract: Using polyacrlonitrile as spinning materials, the paper investigated the factors affecting the preparation of electrospinning filament assembly with directional and parallel alignment. The experimental results showed that, for different receiving electrodes, it is possible to obtain the spinning filament assembly with parallel alignment by adjusting the processing parameters of electrospinning; higher solute concentration and appropriate voltage control are helpful to obtain the spinning filament assembly with parallel alignment.

Abstract: Graft modification is a common means to improve performance of natural polymers. Graft modification of collagen with acrylonitrile in zinc chloride aqueous solution was developed to apply in improvement moisture absorption of synthetic fiber. Polymerization yield, graft ratio and graft efficiency increase at first and then decline following monomer concentration, they reach the top when monomer concentration is 7.0 wt%. Graft ratio and graft efficiency increase at first and then decline following initiator concentration, they reach the top when initiator concentration is 0.2 wt%. Polymerization yield consistently rises with the increasing initiator concentration. Polymerization yield, graft ratio and graft efficiency drop with the increasing collagen concentration. The optimal reaction conditions are: reaction time , 90min; reaction temperature, 60°C; monomer concentration, 7.0 wt%; initiator concentration, 0.2 wt%.

Abstract: As a key stage in wet spinning, compacting process served as a connection between spin and post treatment, it has significant influence on the performances of polyacrylonitrile (PAN) fiber. In this paper, the influences of temperature, time and tension on the compacting process and performance of fibers were studied. The test shows that the suitable compacting process condition is 110°C for 90s with a higher shrinkage ratio. With increasing shrinkage ratio, density and breaking elongation raise, but orientation and breaking strength decrease. To obtain better effect of compacting process, loss of orientation and breaking strength can hardly be avoided; it can be compensated by secondary draw in post process.

Abstract: PTFE suspension latex and PVA solution are blended at different ratio, and the rotary rheometer is used to test the rheological properties of these solutions. The result shows that both PTFE suspension latex and PTFE/PVA blended solution are all shear thinning fluid; with increasing shear rate, apparent viscosity decreases; with increase of PVA content in blended solution, apparent viscosity and Non-Newtonian index increase, and spinnability of blended solution can be improved; with increase of temperature, the apparent viscosity decreases.