Theoretical consideration of the molecular mass distribution of starlike polymers formed by attachment of linear polymers to dendritic cores

Star-shaped polymers can be synthesized by condensation of linear polymers to dendritic cores. The distribution of molecular masses of such hybrid sta r polymers and the factors influencing it have been investigated by calcula tions based on population balance equations and Laplace transformations. Mo reover, the expressions for numerical calculations of molecular mass distri butions have been derived for both Poisson and Schultz-Zimm. types of initi al molecular mass distributions. According to the calculation results, the molecular mass distribution of the star polymers is strongly dependent on t he distribution of the length of linear polymers. Beyond this, the molecula r mass development is affected by several parameters that describe the reac tion degree of dendritic cores, thus, by the fraction of all functional gro ups of dendritic cores involved in grafting, denoted by p; the average bran ching degree of one starlike molecule, represented by rho; or the fraction of dendritic molecules becoming the cores of star polymers, expressed by p/ rho, provided the star molecule contains only one core. (C) 2001 John Wiley & Sons, Inc.