کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1398449 984381 2009 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis and characterization of new copolymers of ethyl methacrylate grafted on tapioca starch as novel excipients for direct compression matrix tablets
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Synthesis and characterization of new copolymers of ethyl methacrylate grafted on tapioca starch as novel excipients for direct compression matrix tablets
چکیده انگلیسی

In last years, the introduction of new materials for drug delivery matrix tablets has become more important. This paper evaluates the physicochemical and mechanical properties of new graft copolymers of ethyl methacrylate (EMA) on tapioca starch (TS) and hydroxypropylstarch (THS), synthesized by free radical polymerization and dried in a vacuum oven (OD) or freeze–dried (FD). Infrared and 13C NMR spectroscopies confirm the change of chemical structure of the copolymers and X-ray diffraction shows up the higher amorphization of copolymers respect to the carbohydrates. Particle size analysis and SEM indicate that graft copolymerization leads to an increase of particle size and a more irregular shape. Graft copolymerization implies decrease of density and moisture content values. Heckel equation shows that copolymers have less densification by particle rearrangement and fragmentation than carbohydrates. Concerning the drying methods, FD products have larger plasticity and lower elasticity than OD copolymers. Graft copolymerization produces a decrease of the applied pressure necessary to obtain tablets, ejection force and friction work. Furthermore, graft copolymers show longer disintegration time than tablets from raw starches. These qualities suggest that these copolymers could be used as excipients in matrix tablets obtained by direct compression, and with a potential use in controlled release.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Polymer Journal - Volume 45, Issue 6, June 2009, Pages 1765–1776
نویسندگان
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