齿科珠状聚甲基丙烯酸甲酯的粒度分布及堆积性能与粉液比的关系

RELATION BETWEEN PARTICLE-SIZE DISTRIBUTION AND PACKING BEHAVIOR OF DENTAL POLY(METHYL METHACRYLATE) BEADS AND POLYMER/MONOMER RATIO

本文采用粉体颗粒特性表征技术 ,对 6组PMMA粉的粒度分布及堆积性能进行测定 ;并测定各组样品的适合粉液比。结果表明 ,近似服从对数正态分布的PMMA粉的粒度分布因平均粒度的不同 ,对其堆积性能产生不同的影响 ;粉液比随着振实空隙率的降低而呈升高趋势。因此 ,通过提高PMMA粉的平均粒度及粒度分布宽度 ,降低堆积空隙率 ,可以在结构上为提高粉液比提供可行性。

The relation between particle size distribution (PSD) of dental poly methyl me-thacrylate (PMMA) beads and polymer/monomer ratio of particles packing was investigated. The particle size and packing behavior of 6 groups of PMMA beads were measured using particles characteristics measurement techniques. The polymer/monomer ratios by weight and by volume were tested and calculated. The results indicated that the packing of PMMA beads with lognormal distributions was different due to the difference of mean particle size and PSD of beads. With decreasing void fraction, the proper polymer/monomer ratio could be increased. Through increasing the mean particle size and PSD of beads, void fraction could be reduced and make it possible to increase polymer/monomer ratio of denture base resin.