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首页> 外文OA文献 >Thermal and rheological approaches for the systematic enhancement of pharmaceutical polymeric coating formulations. Effects of additives on glass transition temperature, dynamic mechanical properties and coating performance in aqueous and solvent-free coating process using DSC, shear rheometry, dissolution, light profilometry and dynamic mechanical analysis.
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Thermal and rheological approaches for the systematic enhancement of pharmaceutical polymeric coating formulations. Effects of additives on glass transition temperature, dynamic mechanical properties and coating performance in aqueous and solvent-free coating process using DSC, shear rheometry, dissolution, light profilometry and dynamic mechanical analysis.

机译：用于系统增强药物聚合物涂料配方的热学和流变学方法。添加剂对使用DSC的水性和无溶剂涂层工艺中的玻璃化转变温度，动态力学性能和涂层性能的影响，采用DSC，剪切流变仪，溶解度，光轮廓仪和动态力学分析。

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摘要

Additives, incorporated in film coating formulations, and their processudparameters are generally selected using a trial-and-error approach. However,udcoating problems and defects, especially those associated with aqueousudcoating systems, indicate the necessity of embracing a quality-by-designudapproach to identify the optimum coating parameters. In this study, theudfeasibility of using thermal and rheological measurements to help evaluate anduddesign novel coating formulations has been investigated. Hydroxypropyludmethylcellulose acetate succinate (HPMCAS), an enteric coating polymer, wasudused as the film forming polymer. Differential Scanning Calorimetry (DSC),udDynamic Mechanical Analysis (DMA), and Parallel Plate Shear Rheometeryud(PPSR) were used to evaluate the effect of different plasticisers on theudperformance of HPMCAS. The results illustrate that, for identical formulations,udthe DSC and DMA methods yielded up to 40% differences in glass transitionudtemperature (Tg) values. Moreover, Tg measured using loss modulus signalsudwere always 20-30 oC less than those measured using tan delta results in DMAudtesting. Absolute and relative Tg values can significantly vary depending on theudgeometry of the samples, clamp size, temperature ramping rate and theudfrequency of the oscillations. Complex viscosity data for different formulationsuddemonstrated a variable shear thinning behaviour and a Tg independentudranking. It is, therefore, insufficient to rely purely on Tg values to determine theudrelative performance of additives. In addition, complex viscosity results,udobtained using both the DMA and PPSR techniques at similar temperatures, areudshown to be comparable. The results from both techniques were therefore usedudto produce continuous master curves for the HPMCAS formulations.udAdditionally, step strain tests showed that HPMCAS chains do not fullyudIIIuddisentangle after 105 seconds as predicted by the Maxwell model. Finally, in situ aqueous-based coating experiments proved that mixtures of triethyl acetyl citrate and acetylated monoglyceride (TEAC/AMG), even without cooling of the suspension, do not cause blocking of the spray nozzle whereas triethyl citrate (TEC) based formulae did. TEAC (alone or in a combination with AMG) exhibits superior wettability to HPMCAS than TEC/AMG formulations and can be used to enhance the efficiency and film quality of the dry coating process.
机译：通常使用反复试验的方法选择掺入薄膜涂料配方中的添加剂及其工艺参数。但是， udcoat问题和缺陷，特别是与水性 udcoat系统相关的缺陷和缺陷，表明有必要采用按设计质量 udappach的方法来确定最佳涂层参数。在这项研究中，已经研究了使用热和流变学测量来帮助评估和设计新型涂料配方的可行性。羟丙基二甲基醋酸纤维素琥珀酸酯（HPMCAS），一种肠溶衣聚合物，被用作成膜聚合物。差示扫描量热法（DSC），动态力学分析（DMA）和平行板剪切流变仪（ud）（PPSR）用于评估不同增塑剂对HPMCAS性能的影响。结果表明，对于相同的配方，DSC和DMA方法的玻璃化转变温度（Tg）值差异高达40％。此外，使用损耗模量信号 ud测得的Tg总是比使用tan delta测得的Tg少20-30 oC，从而导致DMA udtest。 Tg的绝对值和相对值可能会根据样品的预算，钳位大小，温度上升速率和振荡的频率而显着变化。不同配方的复数粘度数据显示了可变的剪切稀化行为和独立于Tg的排名。因此，仅依靠Tg值来确定添加剂的“绝对性能”是不够的。此外，使用DMA和PPSR技术在相似的温度下获得的复数粘度结果可证明是可比的。因此，两种技术的结果都被用于对HPMCAS配方产生连续的主曲线。另外，逐步应变测试表明，如Maxwell模型所预测的那样，在105秒后HPMCAS链没有完全 udIII uddisentangle。最后，原位水基涂料实验证明，即使不冷却悬浮液，乙酰柠檬酸三乙酯和乙酰化甘油单酸酯（TEAC / AMG）的混合物也不会引起喷嘴堵塞，而柠檬酸三乙酯（TEC）的配方确实会阻塞喷嘴。 TEAC（单独或与AMG结合使用）与HPMCAS相比，具有比TEC / AMG配方更好的润湿性，可用于提高干涂工艺的效率和漆膜质量。

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    Isreb Mohammad;

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  • 年度 2011
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