Interpenetrating polymer network principal

All interpenetrating polymer networks utilize two different polymers. The exception involves the homo-IPNs, where both polymers are identical [Millar, 1960 Siegfried et al., 1979]. While these polymers may be synthesized by any of the known methods of polymer synthesis, some methods clearly work better in given objectives than others. The principal kinetic methods used are chain and step polymerization. 

One of the principal features of the compounds discussed above is their ability to be transformed into final products and/or articles from mixtures of almost any composition, even those whose components have little compatibility. The use of oligomers and monomers of various chemical structures expands the assortment of materials and articles that can be produced by combining different components. The interest in so-called hybrid binders, interpenetrating networks, polymer-oligomer systems, and other possible reactive components has increased during recent years. 

The principal methods of mixing two kinds of polymer molecules include mechanical blending, graft copolymerization, block copolymerization, and interpenetration of two networks. The last two are often considered as subgroups of the graft method. 

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