Polymer Properties through Structure

Abstract

Since polymers display an incredible range of properties, their potential for applications is ever increasing. The link between polymer structure and the resulting properties has long been realized, and emerged as the concept of tailor making of polymers. In earlier times, developments were largely targeted on achieving the desired properties through new monomers, copolymer and blend compositions, physical and chemical additives, and control of polymer molecular weights, as well as through structural changes derived from processing. In recent years, the increased expertise in anionic polymerization and the emergence of controlled radical polymerization techniques have led to relatively easy access to several precisely controlled topologies such as those of telechelic, block, graft, star-shaped, and several other branched homoploymers and copolymers with controlled molecular weights. For example, phenomenal growth has been recorded in the area of synthesis of block copolymers, as well as in examination of their self-assembling characteristics leading to unique control of nanoscale morphology. This is providing tools for development of properties suitable for applications extending from those requiring mechanical toughness to electronic and biological uses. Another rapidly developing area is nanocomposites, where the attainable range of properties is further expanded by incorporating inorganic and organic nanoparticles in polymeric matrices.In this chapter we aim to demonstrate the relationship of the structure of polymers with their thermal, solution, and rheological behavior. Besides providing a general review of such behavior, we will emphasize some of the recent developments in these areas. Thermal Properties of PolymersThe thermal behavior of polymers is different from that of simple compounds in that, on heating, the transition of polymers from solids to liquids occurs not at

Synthesis and Characterization of Model Dumbbell Polymers

“…The design of novel architecture branched polymers has received a lot of attention due to their applications in rheology modification, mechanical performance, biomedical areas, and microelectronics. − In addition, polymers with controlled architecture provide opportunities toward a better understanding of the effects of topology on dynamics of complex macromolecules. Extensive investigations in the past have addressed the behavior of branched polymers such as star, comb, hyperbranched, H-shaped polymers, super-H-shaped polymers, and pompom polymers.…”