Relationship between Degree of Polymeric Ionisation and Hydrolytic Degradation of Eudragit® E Polymers under Extreme Acid Conditions
Relationship between Degree of Polymeric Ionisation and Hydrolytic Degradation of Eudragit® E Polymers under Extreme Acid Conditions
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DOI：
10.3390/polym11061010
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发表时间：
2019-06-01
期刊：
影响因子：
5
通讯作者：
Salamanca, Constain H.
中科院分区：
文献类型：
--
作者：
Linares, Valentina;Yarce, Cristhian J.;Salamanca, Constain H.
市售共聚物Eudragit（R）E 100和Eudragit（R）PO是在制药领域中作为包衣系统广泛使用的材料。在酸化条件下衍生自氨基甲基丙烯酸酯基团的此类材料可获得可电离部分或经历聚合物结构的水解降解。这项工作的重点是建立两个再加工的聚合物材料，在这里命名为EuCl-E-100和EuCl-E-PO，这是从商业Eudragit（（R））E 100和Eudragit（（R））E PO，分别获得的化学，物理和表面变化。将商业材料暴露于极端酸性条件下，其中聚合物溶解并随后通过折射窗口方法干燥。所获得的材料的化学特征通过电位滴定，核磁共振光谱（H-1 NMR和C-13 NMR）在一个和两个维度（COSY，HSQC，和HMBC），红外光谱，X-射线衍射，和差示扫描量热法。通过研究流动性、可润湿性及其增湿和减湿能力，评价了材料物理性质的变化。通过使用座滴法测量接触角进行表面热力学研究。结果表明，加工的聚合物材料获得了相当程度的电离，而不经历酯化基团的水解。此外，这种变化改善了材料的流动特性和在pH > 5的水性介质中的溶解度，同时还保持了聚合物表面的疏水性程度。
The commercial copolymers Eudragit((R)) E 100 and Eudragit((R)) PO are widely used materials in the pharmaceutical field as coating systems. Such materials derived from amino-methacrylate groups under acidulated conditions may acquire an ionisable fraction or undergo hydrolytic degradation of the polymeric structure. This work focused on establishing the chemical, physical, and surface changes of two reprocessed polymeric materials, here named as EuCl-E-100 and EuCl-E-PO, which were obtained from the commercial Eudragit((R)) E 100 and Eudragit((R)) E PO, respectively. The commercial materials were exposed to extreme acid conditions, where the polymers were solubilised and subsequently dried by the refractance window method. The materials obtained were chemically characterised by potentiometric titration, nuclear magnetic resonance spectroscopy (H-1 NMR and C-13 NMR) in one and two dimensions (COSY, HSQC, and HMBC), infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. Changes in the physical properties of the materials were evaluated through studies of flowability, compactability, and their ability to gain and lose humidity. Surface thermodynamic studies were carried out through contact angle measurements using the sessile drop method. The results showed that the processed polymeric materials acquired a substantial degree of ionisation without undergoing hydrolysis of the esterified groups. Furthermore, such changes improved the flow characteristics of the material and the solubility in aqueous media at pH > 5, while also maintaining the hydrophobicity degree of the polymeric surface.