Polymer nanocomposites comprise a new class of material as the physical properties of polymers can be improved by incorporating nanoparticles. Also the inorganic-organic bicomponent nanocomposites have been studied recently due to their comprehensive applications in a field of engineering, and appropriate advantages for mechanical properties where nanoparticles are finely dispersed within a matrix. In this research, we prepared polymer/nanometal composites through the conventional sheath-core spinning process, and analyzed their characters with WAXS and SEM.
A sheath-core bicomponent fiber was melt-spun by co-extrusion of polypropylene (PP) as the sheath and master batch (polypropylene-Ag) as the core. The Ag nanopowder was obtained from surfactant system by reduction of silver nitrate with hydrazine. The master batch was prepared in conventional extruder and classified into Ag of 3wt.% and of 10wt.%. Then we made the PP/Ag nanocomposite fiber using a conventional conjugate spinning. Wide-angle X-ray scattering (WAXS) was measured with an X-ray diffractometer (at 40 kV, 100 mA) and scanning electron micrographs (SEM) were obtained at 5.0 kV.
Fig. 1 shows the X-ray diffraction patterns of the 100% PP fiber, the core-sheath fiber from 3wt.% master batch, and the core-sheath fiber from 10wt.% master batch respectively. PP is well known as a crystalline polymer, and had the diffraction peaks at 2q = 14.7°, 21.2° (2q: diffraction peak angle). And the pure phase of Ag nanoparticles was obtained through the prepared nanocomposites (2q = 38.0°, 44.3°, 64.5°). They elucidate the crystallinity of PP was decreased with increasing of Ag contents.
Scanning electron microscopy shows the Ag nanoparticles are in sphere shape with 30~50 nm average diameter in the core-section of nanocomposites at the 10 wt.% master batch (Fig. 2). The nanoAg particles had a good dispersion in matrix polymer. The SEM photograph shows also very little aggregation of the nanoAg particles
By: Sang Young Yeo, Hoon Joo Lee, and Sung Hoon Jeong* Department of Fiber & Polymer Engineering, Hanya
Submit Date: 12/31/1999 20:00