【作者】 张庆鸿；

【导师】 吴恩格；

【作者基本信息】 昆明医学院 ， 口腔临床医学， 2003， 硕士

【摘要】 目的：基于周内外主要石膏模型材料生产工艺及原理，结合现代树脂类材料发展趋势，对传统生产工艺进行探索性改良，旨在对半水石膏合成中的一些影响因素进行分析，于制作工艺方面提高石膏纯度，使合成的石膏模型材料在一定程度上能改善现代石膏模型材料存在的机械强度不足和表面硬度较差的问题。 方法：对蒸馏水、氯化钙及丁二酸钠三大影响因素进行试验分组。采用高纯度的二水硫酸钙、氯化钙及丁二酸钠为原料，并于试验组研制石膏中加入辅助添加剂硫酸钾、氧化钙和阿拉伯树胶。在对传统石膏生产工艺探索改进后，严格控制生产工艺中压强和温度进行石膏模型材料的合成，并与对照组上海贺利氏超硬石膏主要物理机械性能对比。采用统计学方法进行分析，P＜0.05时具显著性差异(a=0.05) 结果：在试验中观察到蒸馏水量对半水石膏合成影响较大，当蒸馏水与原料比为150ml：100g时效果较好；而氯化钙及丁二酸钠影响较小，当氯化钙与二水硫酸钙质量比为1：2，丁二酸钠为0.75％时效果较好。经过大量探索性研究，参照并改进国内外主要生产工艺后，研制石膏终品生产工艺参数为：蒸馏水与生料比为165ml：100g；氯化钙与二水硫酸钙质量比为1：2，丁二酸钠为0.75％时效果较好；缓慢升温至142℃，0.3Mpa时恒温恒压6h；干燥温度120℃，4h。试验组研究石膏与对照组上海贺利氏超硬石膏性能比较如下：主要成份半水硫酸钙分别为91.61％，88.51％，且两者晶形均以标准六面短棱柱状居多；布氏硬度分别为13.3±0.2927HB，8.98±0.5193HB；抗压强度分别为56.30176±2.45594MPa，53.03302±3.416lOMPa；抗弯强度分别为9.634±0.73645MPa，14.683±1.01473MPa；膨胀率分别为9.250E-02±2.5000E-02，9.000E-02±5.1335E-02；混水率分别为20%，22%。统计学分析显示:试验组与对照组性能比较中布氏硬度及抗弯强度间可见显著性差异(P<0.05);抗压强度间未见显著性差异(P>0 .05);膨胀率间也未见显著性差异(P>>0.05)。结论:蒸馏水量对结果影响较大;抓化钙和丁二酸钠对半水石膏合成的影响较小;试验组研制石膏与对照组上海贺利氏超硬石膏在主要物理机械性能方面基本相似。更多还原

【Abstract】 [Objective] To base on domestic and oversea productive technology and principle of gypsum, to combine with development of modern resin, and to improve traditional productive technology exploratively, the aim is to analyze influential factors in the course of synthesis of hemihydrated gypsum, enhance purity of hemihydrated gypsum on productive technology, synthesize a kind of dental gypsum and research preliminary on these existing questions about insufficient mechanical strength and worse surface hardness of present gypsum of molding materials to certain extent. [Methods] To classify these three influential factors as distilled water group, Calcium Chloride gypsum and sodium Succinate group. To adopt high purity of dehydrated gypsum, Calcium Chloride and sodium Succinate as raw materials, and add supplementary additives into test group’s study gypsum, additives are Postassium Sulfate, Calcium Oxide and Gum Arabic. After improving traditional productive technology of gypsum exploratively, to synthesize hemihydrated gypsum through controlling strictly pressure and temperature in the course of productive technology, and compare study gypsum’s physical and mechanical properties with Shanghai Heraeus superhard gypsum’s of control group. To analyze results through statistical methods, and possess significant difference when P<0.05(a=0.05). [Results] To observe that effect of volume of distilled water on synthesis of hemihydrated gypsum is bigger, and the effect better when distilled water: raw materials as 150ml:100g; whereas effect of Calcium Chloride and sodium Succinate smaller, and the effect better when Calcium Chloride: dehydrated gypsum as 1:2, sodium Succinate as 0.75%. after lots of explorative researches and refer to domestic and oversea main productive technology ,the productive technology’s parameters of study gypsum are as follows: distilled water: raw materials as 165ml : 100g, Calcium Chloride : dehydrated gypsum as 1:2, sodium Succinate as 0.75%; vapouringtemperature as 142℃, pressure as 0.3Mpa, time as 6h, drying temperature as 120℃, time as 4h. Comparison study gypsum’s properties of test group with Shanghai Heraeus superhard’s of control group is as follows: percentage of hemihydrated gypsum, crystal shape, Brinell hardness, compressive strength, bending strength, expanding ratio and water/powder(W/P) are, respectively, 91.61%, 88.51%, short prism; 13.3@0.2927HB, 8.98 @ 0.5193HB; 56.30176 @2.45594Mpa, 53.03302 @ 3.41610Mpa; 9.634 @ 0.73645Mpa, 14.683 @ 1.01473Mpa; 9.250E-02@2.5000E-02, 9.000E-02@5.1335E-02; 20%, 22%. Statistical analysis indicates: significant difference is observed between Brinell hardness and bending strength of the test group and the control group’s (P<0.05); significant difference is not observed between two groups’ compressive strength (P>0.05); in addition, significant difference is not observed between two groups’ expanding ratio, either.[Conclusion] Effect of volume of distilled water bigger; but effect of Calcium Chloride and sodium Succinate smaller. Study gypsum’ s physical and mechanical properties of test group is basically similar to Shanghai Heraeus superhard gypsum’s of control group.更多还原