Comb macromolecules with attracting functional groups in side chains

The conformational behavior of a single comb-shaped macromolecule with associating groups in side chains was studied by means of Monte Carlo simulation. The side chains contain two types of units, type A representing nonfunctional units (main chain units are likewise classified with type A) and type B representing functional (attracting) units. As a result of an increase in attraction energy between associating groups, the transition of the macromolecule from coil to the globule state takes place. The coil-globule transition is accompanied by segregation of unlike units; as a result, the globule has a complex structure: the core of the globule is formed by attracting groups of side chains, and the envelope is formed from soluble units of both main and side chains. The dependence of the size and shape of the macromolecule on its structural parameters, such as the length of main and side chains and the graft density of side chains, and on the position of the functional groups in side chains was examined. Along with the single globule, conformations in which the attracting units of side chains formed several bead globules were observed.