Semi-IPNs definition

Silicone co-polymer networks and IPNs have recently been reviewed.321 The development of IPNs is briefly described, and the definitions of the main (non-exclusive) classes of the IPNs are cited. Examples of latex IPNs, simultaneous and sequential IPNs, semi-IPNs, and thermoplastic IPNs are provided. The use of silicone-silicone IPNs in studies of model silicone networks is also illustrated. Networks in which siloxane and non-siloxane components are connected via chemical bonds are considered co-polymer networks, although some other names have been applied to such networks. Today, some of the examples in this category should, perhaps, be discussed as organic-inorganic hybrids, or nanocomposites. Silicone IPNs are discussed in almost all of the major references dealing with IPNs.322-324 Silicone IPNs are also briefly discussed in some other, previously cited, reviews.291,306... 

If only one element is cross-linked, the resulting system is defined as semi-lPN of which the lUPAC definition is the following a polymer consisting of one or more networks and one or more linear or branched polymers differentiated by the diffusion on a molecular scale [39, 44]. Semi-lPNs are different from IPNs since the constituent linear or branched polymers can, in principle, be separated from the component polymer networks without breaking chemical bonds they are polymer blends. 

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