壳聚糖用于氧化铝凝胶注模成型

Alumina gel-casting using chitosan

介绍了一种新的凝胶注模成型系统.采用醋酸为溶剂、壳聚糖为单体凝,以戊二醛为交联剂,引发聚合反应,形成的亚胺键相互交联成网状结构,原位成型氧化铝坯体.通过红外光谱、扫描电镜、抗弯强度仪等检测,表征凝胶体系、Al2O3坯体的微观形貌及坯体强度性能.结果表明,在室温下调节料浆pH值为3～4,分散剂聚丙烯酸胺用量占料浆质量的0.4%,球磨混料2 h左右,可制备出固相体积分数为52%,粘度为550 Mpa·s的氧化铝瓷的料浆.固化成型,经室温和加热两阶段干燥,可得到强度达25.8 Mpa的坯体.

This paper describes a novel kind of gel-casting system, using chitosan solved in diluted acetic acid and polymerized with glutaraldehyde. The imine（-C= N-） bonds facilitates the gelation of chitosan and giutaraldehyde. The ceramic powder added does not destroy the bonding structure of the gel. The physical properties of the slurry,gel and green body are characterized by FTIR, SEM, and strength meter, respectively. The results indicate that at room temperature, alumina slurry is prepared by regulating the slurry pH value from 3 to 4, mixing 0.4% PAANH4 and ball-milling for 2 hours. Solid concert of alumina slurry （volume fraction） is up to 52% and viscosity, up to 550 MPa·s. A body of 25.8 MPa in strength is obtained by solidication molding after room temperature ageing and heating.