The Structure and Properties of Polymeric Materials.

A total of thirty-five publications have been generated from this research appearing in thirteen primary journals. The connection between two traditional theoretical approaches to the treatment of rubber elasticity has been bridged. One of these is the theory of phantom networks, developed originally by James and Guth, in which the integrity of the chains is ignored and the junctions cross linkages are allowed to seek their preferred positions without regard for the entanglements of chains that severely limit configurational rearrangements in real systems. The other follows the precepts of W. Kuhn, elaborated by Wall, Treloar, Flory and Rehner and others, according to which the cross linkages are firmly embedded in their surroundings and hence must undergo affine displacements in proportion to the macroscopic strain. This research suggests that the unswollen network at small deformations conforms approximately to the affine behavior, but that it approaches the phantom model at high elongations andor high degrees of swelling. Decreases with strain and dilution may account for departures from the theoretical relationship. The theory of order-disorder in systems of rigid extended polymer chains and of phase equilibria in such systems Proc. Roy. Soc. London, A234, 73 1956 has been adapted without difficulty to semiflexible chains consisting of rigid rod-like segments connected by flexible joints. Author