メカニカルミリングによるPVA粉末の非晶質化 Amorphization of PVA Powder Subjected to Mechanical Milling
The mechanical milling of PVA(polyviny l alcohol) under an Ar atmosphere was carried out at room temperature. So far, no complete amorphous PVA has been reported to be synthesized by any other methods. Bragg peaks of the crystal phase in the PVA, however, became broadened with increasing milling time. After 200 hours of milling a halo pattern dominated. The result, therefore, led us to conclude that the amorphization of the PVA was caused by the mechanical destruction of the crystal structure. The amorphization of the PVA was also confirmed through the observation of low energy excitation by inelastic neutron scattering. A drastic change within 5Å in the radial distribution function RDF(r)was not observed. On the contrary, the correlation distance of the atomic distribution became shorter with increasing milling time. The results suggest that the milling transforms straight long chain molecules into tangled ones in PVA.
粉体および粉末冶金 43(6), 726-730, 1996-06-15
Japan Society of Powder and Powder Metallurgy