Thermoplastic apparent IPNs

Although this definition still fits most materials called IPNs, now some hybrid polymer blends, such as thermoplastie ayyarent IPNs, call for a broader concept [3,7,8]. In contrast to the chemically crosslinked IPNs, physical bonds are characteristic of the crosslinking in thermoplastic apparent IPNs. These physical bonds are glassy domains of block copolymers, ionic clusters in iono-mers, or crystalline domains in semicrystalline polymers. The components of thermoplastic IPNs are capable to form physical networks and are characterized by interpenetration of phases. Thermoplastic apparent IPNs take an inter-... 

In this chapter, structure-property relationships in new thermoplastic apparent IPNs (AIPNs) and in semi-IPNs containing a polyurethane thermoplastic elastomer are discussed. 

JLnterpenetrating polymer networks (IPNs) are a special class of polymer blends in which the polymers exist in networks that are formed when at least one of the polymers is synthesized or cross-linked in the presence of the other. Classical or true IPNs are based solely on thermosetting polymers that form chemical cross-links. More recently, two classes of thermoplastic IPNs have been developed. Apparent IPNs are based on combinations of physically cross-linked polymers. Semi-IPNs are based on combinations of... 

In Table 2, there is an apparent gap of two decades (1977-1997) between thermoplastic IPNs and the modem IPN nomenclature in fact many people were busy characterizing a number of new materials and developing their apphcations, as described above. Application-oriented papers and patents are delineated below. 

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