Microscopic Fourier transform infrared/differential scanning calorimetry system used to study the different thermal behaviors of polymethacrylate copolymers of eudragits RS, RL, E 30D, or E

Abstract

The thermal stability of Eudragits RL, RS, E 30D, and E films was qualitatively investigated by the reflectance Fourier transform infrared microspectroscopy equipped with differential scanning calorimetry (FTIR/DSC microscopic system). DSC and thermogravimetric analysis (TGA) were also used to study the thermal behavior of the granules of the raw material and the film of these polymers. The results indicate that the Eudragit RL, RS, or E 30D polymer exhibited a higher thermal‐stable behavior, but Eudragit E easily formed the six‐membered cyclic anhydride through heating process via the inter‐ or intramolecular ester condensation. The leaving group in Eudragit E molecule was larger than that in Eudragit E 30D, and the leaving group of salt in Eudragit RS or RL was too stable to polycondense. The DSC thermograms and TGA curve also confirmed this result. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 829–835, 2000

Plasticized Drug‐Loaded Melt Electrospun Polymer Mats: Characterization, Thermal Degradation, and Release Kinetics

“…The melt viscosity of pure EPO is one order of magnitude larger at all melt temperatures than that of with API (and plasticizer) content. An extrapolation indicates that MES temperature of EPO would be over 180°C, at which, however, a severe decomposition reaction is induced, thus EPO is not convenient for MES as a pure polymer. The addition of CAR alone to the polymer lowered, however, the viscosity dramatically, enabling fiber formation at a reduced 155°C temperature.…”

“…The results are shown in Table , the impurities could be precisely determined according to the small deviations between the repeated measurements. The polymeric matrix and the plasticizers can be considered as thermally stabile compounds used in practice . In order to differentiate between the thermal effects of extrusion and MES steps, the extrudates and the melt electrospun fibers were measured separately.…”

Physicochemical characterization and drug release properties of PDMAEMA/OSA Semi‐IPN hydrogels with microporous structure

“…These results are consistent with literature reports. It is known that the T g of PDMAEMA and copolymers on the base of DMAEMA are below 100°C 30–32…”

Preparation and Evaluation of Sustained-Release Matrix Tablets Based on Metoprolol and an Acrylic Carrier Using Injection Moulding

“…Previous studies have reported that Eudragit RL and RS are thermostable up to 167°C, and metoprolol is stable below 160°C, the process temperatures selected in this study were always below the onset of degradation of each component (3,18). In addition, DSC measurements were conducted up to 180°C on individual components and physical mixtures, and no evidence of thermodegradation was found in all thermograms.…”