STATISTICAL PROPERTIES OF CONFINED MACROMOLECULES

The review presents in a consistent manner the results of a rigorous t heory which describes the equilibrium behaviour of an isolated macromo lecule in a porous medium. An exactly solvable model of a macromolecul e in a slit-like pore is used as the base model. Various behavioural r egimes are analyzed for a macromolecule in a pore, realizable at vario us molecule-to-pore size ratios, as also with varied adsorption intera ctions. The effect of polymer chain rigidity is discussed, and so is t he specific behaviour of a macromolecule in different forms of pores. Presented also are the results of a rigorous theory for ideal cyclic m acromolecules in pores under conditions of varied adsorption interacti ons. Theory is compared with experimental results on the partition coe fficients of macromolecules at no adsorption and with adsorption inter actions taking place. Comparing theory with experiment enables determi nation of a correlation length of adsorption for various polymer-solve nt-adsorbent systems. The basic results are discussed in terms of the scaling theories which account for the excluded volume effects and for the effect of the thermodynamic quality of the solvent upon the behav iour of linear and cyclic macromolecules in pores. Alongside the discu ssion on the properties of individual confined macromolecules, another situation is analyzed: that where a molten amorphous polymer is in co ntact with solid particles. Various approaches are examined toward des cribing such systems. It is suggested and justified that the conformat ions of flexible-chain macromolecules in an amorphous polymer amidst f iller particles are identical to the conformations of an isolated chai n at the critical adsorption interaction energy.