Polyacrylates, microencapsulation

Polyacrylate-polymethacrylate copolymers (Eudragits) are widely used as tablet adjuvants and coating polymers [1]. These polyacrylate polymers were also used for the microencapsulation of... 

Microencapsulation of Live Animal Cells Using Polyacrylates... 

Nevertheless we have chosen an alternative approach microencapsulation using synthetic polyacrylates which may be stronger and more biocompatible (or at least have a more reproducible biocompatibility). Most of the effort has been with a particular water insoluble synthetic copolymer (HEMA-MMA), although other polyacrylates (water soluble or insoluble) have been used. In general, two approaches have been used complex coacervation with water soluble polycations and polyanions to generate an insoluble complex and simple coacervation with a water insoluble polymer precipitated from an organic solvent. 

The encapsulation experience with EUDRAGIT RL lead to the conclusion that EUDRAGIT RL, while appropriate for demonstrating in a general sense that water insoluble polyacrylates could be used to microencapsulate live mammalian cells, was not suitable for the particular problem of encapsulating cells because of its limited biocompatibility and permeability. To address both of these limitations (and especially the former one), a series of noncrosslinked... 

The present volume comprises five review articles written especially for this series by leading authorities in the field. The first three adresses major structural characteristics of biodegradable polymers. Robert Lenz provides athorough review of biodegradable polymers. Jorge Heller offers a critical analysis of the structure, properties and medical applications of polyorthoesters, whereas Abraham Domb and his associates offer the same critical analysis of polyanhydrides. Eric Doelker discusses the structure and properties of cellulose derivatives. Finally Michael Sefton presents the use of polyacrylates for the microencapsulation of live animal cells. 

Bryant and Colvin produced a fibre with integral microcapsules with PCMs or plastic crystals. The fibre has enhanced thermal properties at predetermined temperatures. The microcapsules can range in size from about 1 to about 10 microns. In fabricating the fibre, the desired microencapsulated PCMs are added to the liquid polymer, polymer solution or base material and the fibre is then expended according to conventional methods such as dry or wet spinning of the polymer solutions and extrusion of the polymer melts. According to the report, the maximum content of PCM in the polyacrylic fibre is about 10%. The minimum filament denier is 2.2dtex. ... 

Sefton MV, Stevenson WTK. Microencapsulation of live animal cells using polyacrylates. Adv Polym Sci 1993 107 143-197. 

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