Interpenetrating polymer networks are combinations of two or more polymer networks that are at least partly interlocked on a molecular scale without being covalently joined [1]. Each network is synthesised or crosslinked in the presence of the other, so the two are entangled and cannot be separated without breaking chemical bonds [1]. The morphology is set by the relative rates of network formation and by the compatibility of the components, which decide whether the phases stay co-continuous or separate into domains [2]. Because the networks carry no bonds between them, the material is classed as a polymer blend rather than a copolymer [3]. Swelling in a common solvent is limited by the elastic restraint each network imposes on the other [2].
Synthesis and properties of polymers·Polymers and Plastics·Materials Science·Physical Sciences