CARBONACEOUS GEL BEAD;
WATER-IN-OIL EMULSION;
POLY(VINYLALCOHOL);
SURFACE MORPHOLOGY;
D O I:
10.1016/0008-6223(95)00001-T
中图分类号:
O64 [物理化学(理论化学)、化学物理学];
学科分类号:
070304 ;
081704 ;
摘要:
Carbonaceous gel beads were prepared by addition of polymers using ammonia water of amphiphilic carbonaceous material through water-in-oil emulsion. By addition of poly(vinylalcohol), carbonaceous gel beads having dimples were obtained, where the number and size of dimples were dependent on the additive amount and molecular weight of poly(vinylalcohol). However, only beads with smooth surfaces were obtained by addition of poly(vinylpyrrolidone) and poly(ethyleneglycol). The morphology of beads is significantly influenced by interfacial tension at the water-oil interface. The surface area of beads prepared by addition of polymers remarkably increased by heat treatment from 5 m(2) g(-1) to 289 m(2) g(-1) and a pore size of about 20 Angstrom was predominantly produced in the case of PVA. In addition, the carbonaceous gel prepared by addition of PVA exhibited a high graphitizability, similar to that of green cokes. Thus, it was found that physicochemical properties of gel beads prepared by addition of PVA are significantly altered.