Nanocapsules with Non-Radical Polymerizations in Miniemulsion

As shown above, the miniemulsion polymerization is not hrnited to polymers obtained by radical polymerization. In the following section some examples will be provided for specific polymers. 

Polyaddition in miniemulsion was also performed using chitosan as stabilizer with two biocompatible costabihzers, JefFamine D2000 and Gluadin. A linking diepoxide in the presence of an inert oil results, via an interface reaction, in thin - but rather stable - nanocapsules. Since both water- and oil-soluble aminic costabilizers can be used, these experiments show the way to a great variety of capsules with different chemical structure. Such capsules are expected to be biocompatible and biodegradable, and may find applications in drug delivery [27]. 

Chitosan is a biodegradable, nontoxic and naturally occurring polymer of P-( 1-4)-2-amino-2-deoxy-D-glucopyranose. It is prepared by the partial alkahne deacetyla- 

An enhancement of stabilization was obtained by using CTM A-Cl, which allows high solid contents and the synthesis of very small particles with diameters 100 nm. However, CTMA-Cl was chosen as a cross-test to highlight the deficiencies of the system, since its use is prohibited by demands of biocompatibility and biodegradability. 

The synthetic biocompatible polymer, Jeffamine D2000, which was shown earlier to have interfacial properties [24], was added to the monomer phase to ensure cationic stabilization of the weak spots during the polymerization process. In this case, high solid contents were obtained when adding only small amounts of Jeffamine (0.5 to 2.5 wt.% with respect to the monomer phase), and very small and monodisperse latexes in the size range ca. 100 to 200 nm without any coagulate could easily be synthesized. It is interesting to note that when the Jeffamine con- 

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