高固相含量羟基磷灰石浆料的制备及凝胶浇注成型

Processing of High Solid Content Hydroxyapatite Slurries and Gel-Casting

为提高羟基磷灰石(HAP)浆料在水分散体系中的稳定性,获得良好的固化性能,采用二甲基丙烯酰胺(DMAA)作为单体,N,N′-亚甲基双丙稀酰胺(MBAM)作为交联剂,偶氮二咪唑啉丙烷(AZIP)为引发剂,研究了不同分散剂含量和不同固相含量HAP浆料的流变性.使用自制的亚微米级粉体原料,制备了固相含量高达55%(体积分数)的稳定浆料,并成功实现了浇注成型.获得相对密度高达57.5%的素坯,其抗压强度、抗弯强度最高值分别达到(37.0±6.5)和(13.8±1.0)MPa.经1250℃无压烧结2h,HAP陶瓷具有优良的烧结性能,相对密度为98.7%,抗弯强度和弹性模量分别达到了(85.3±9.9)MPa和(133.0±10.2)GPa.

An aqueous gel-casting of hydroxyapatite using a new polymeric system was investigated. The monomer, cross-linker, and initiator were dimethylacrylamide （DMAA）, N,N′-methylenebisacrylamide （MBAM）, and 2,2′-azobis[2-（2-imidazolin-2-yl）propane] （AZIP, respectively）. The rheological properties of the gel-casting slurries and influencing factors were studied. The relative density, compressive strength, and flexural strength of green body were 57.5%, （37.0±6.5）, and （13.8±1.0） MPa, respectively. After presureless sintering at 1250 ℃ for 2 h, the relative density of the final product is about 98.7%. Bending strength and elasticity modulus are （85.3±9.9） MPa and （133.0±10.2） GPa, respectively.