Chapter 11 - Interpenetrating Polymer Networks

Abstract

Publisher Summary This chapter provides an overview of the interpenetrating polymer network (IPN) that denotes an entire class of materials, rather than a single molecular topology. An IPN is any material containing two polymers, each in network form. Both the polymers are synthesized or cross-linked in the presence of each other. It explains both simultaneous and sequential types of syntheses, and both yield distinguishable materials. Further, the chapter discusses the relationship among IPNs, blends, and grafts. A polymer blend is defined as a combination of two polymers without any chemical bonding between them, whereas a graft copolymer refers to a product prepared by the polymerization of monomer II in the presence of polymer I, with greater or lesser extent of actual graft copolymer formation. Recent electron microscope and kinetic evidence suggests that grafting in many systems is less extensive than previously believed, but it is still important. The chapter additionally highlights the morphology that indicates phase separation. The phases vary in amount, size, shape, sharpness of their interfaces, and the degree of continuity. The chapter also describes the factors that affect morphology of the material and the physical and mechanical behavior.