Statistical Properties of the Semibatch Self-Condensing Vinyl Polymerization System in the Presence of Multifunctionality Core Initiators

We present a systematic investigation of the semibatch process in the self-condensing vinyl polymerization (SCVP) system in the presence of multifunctionality core initiators. This is based on the fact that such a semibatch polymerization system is exactly a multistep process, involving preexisting polymers at the beginning of each step. For this purpose, a generating function (GF) method is proposed for the present SCVP system with any initial distribution of preexisting polymers. This is demonstrated to be especially useful to investigate the semibatch process, allowing a sequence of feedings during the polymerization. Consequently, the number-, weight-, and z-average molecular weights as well as the polydispersity index of hyperbranched polymers (HBPs) can be explicitly obtained. They are determined by the predetermined schedule, including feeding details and reaction parameters at each step. Therefore, the GF method has provided a unified treatment on the semibatch SCVP system. By doing so, an optimized predetermined schedule can be employed to design the semibatch reactor and prepare HBPs with desired properties.