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Studies on the influence of composition and processing on the mechanical properties of pellets and compacted pellets.

机译：研究组成和加工对颗粒和压实颗粒力学性能的影响。

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摘要

A study on the influence of formulation and processing factors on the mechanical properties of pellets produced by extrusion and spheronization has been conducted. Microcrystalline cellulose (MCC) was mixed with lactose or glyceryl monostearate (GMS) in different proportions. Similarly, mixtures of water with ethanol or glycerol were used as liquid binders. Based on the different rate of moisture removal, and means of heat and mass transfer, four different drying techniques namely: hot-air oven drying, freeze-drying, fluid-bed drying, as well as desiccation with silica-gel were used in the production of pellets. In addition, pellets containing model drug (paracetamol) and having different mechanical properties were prepared and coated with an aqueous dispersion of ethyl cellulose (SureleaseRTM).;Statistical analysis established that freeze-drying, fluid-bed drying, and rapid evaporation of ethanol produced porous pellets which were weak, deformable, less strainable and resulted in rigid compacts. The strength and nonconnective nature of MCC was modulated by the incorporation of lactose, GMS, or glycerol. The brittle fracture, as indicated by Weibull modulus, of the lactose-rich pellets created new surfaces to form stronger compacts. Improvement in the deformability of the pellets with the addition of GMS, produced strong tablets with the lowest surface roughness. The increase in phase angle, determined by DMA, highlighted the increase in the viscous nature of the pellets as a result of coating.;A range of properties from a simple fracture load to detailed load/displacement curves were used to characterize the pellets in terms of their tensile strength, deformability, linear strain elastic modulus and shear strength. Additionally, dynamic mechanical analysis (DMA) established the viscoelastic properties of uncoated and coated pellets. A non-contact laser profilometer was also used to quantify the permanent structural change of the pellets after compaction. The Heckel plot, Kawakita compressibility constant, pressure/displacement and logarithm of pressure/density profiles were employed to study the compaction mechanism of the pellets. Compacted pellets were investigated in terms of their strength and volumetric elastic recovery.
机译：已经进行了关于配方和加工因素对通过挤出和滚圆法制得的颗粒的机械性能的影响的研究。将微晶纤维素（MCC）与乳糖或单硬脂酸甘油酯（GMS）以不同比例混合。类似地，水与乙醇或甘油的混合物用作液体粘合剂。根据不同的水分去除速率以及传热和传质的方式，在干燥过程中使用了四种不同的干燥技术：热风烤箱干燥，冷冻干燥，流化床干燥以及硅胶干燥。生产颗粒。此外，制备了包含模型药物（扑热息痛）且具有不同机械性能的药丸，并用乙基纤维素的水分散液（SureleaseRTM）进行包衣。统计分析确定了冻干，流化床干燥和乙醇快速蒸发的产生多孔的颗粒，其较弱，易变形，不易拉紧并产生刚性压坯。 MCC的强度和非连接性是通过掺入乳糖，GMS或甘油来调节的。如威布尔模量所示，富含乳糖的药丸的脆性断裂产生了新的表面，从而形成了更坚固的压坯。通过添加GMS改善粒料的可变形性，可生产出具有最低表面粗糙度的坚固片剂。由DMA确定的相角的增加突出了包衣的结果是颗粒的粘性增加。;从简单的断裂载荷到详细的载荷/位移曲线的一系列特性被用来表征颗粒它们的抗张强度，可变形性，线性应变弹性模量和剪切强度。此外，动态力学分析（DMA）建立了未包衣和包衣颗粒的粘弹性质。非接触式激光轮廓仪也用于量化压实后颗粒的永久结构变化。利用Heckel图，Kawakita可压缩常数，压力/位移和压力/密度曲线的对数来研究颗粒的压实机理。研究了压实颗粒的强度和体积弹性回复率。

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  • 作者

    Bashaiwoldu, Abraham Bahre.;

  • 作者单位

    University of London, University College London (United Kingdom).;

  • 授予单位 University of London, University College London (United Kingdom).;
  • 学科 Pharmaceutical sciences.
  • 学位 Ph.D.
  • 年度 2002
  • 页码 340 p.
  • 总页数 340
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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