Effect of Feed Rate on Structure of Hyperbranched Polymers Formed by Self-Condensing Vinyl Polymerization in Semibatch Reactor

Abstract

Hyperbranched polymers (HBPs) formed by a self-condensing vinyl polymerization (SCVP) of copolymerization of AB* monomers slowly added into trifunctional C 3* cores under various feed rates were investigated by a kinetic model. The dependences of average molecular weight, polydispersity, degree of branching, and number of structural units of the hyperbranched polymers on the feed rate were calculated by a generating function method. It was found that the final polydispersity index (PDI) can be attained below 1.5 by a slow addition of AB* at a feed rate parameter, φ, less than 2. While the AB* monomers fed quickly, the system with a lower content of the C 3* cores results in a broader molecular weight distribution. A high degree of branching, about 0.66, can be achieved by addition of AB* monomers into a small amount of C 3* cores at φ lower than 10.

Statistical thermodynamic properties of a new self-condensing vinyl polymerization system

“…Theoretically, a series of investigations on HBPs have been performed through different methods such as probabilistic analysis [8], solving kinetic differential equations [15][16][17][18], computer simulation [19][20][21], and generating function method [22][23][24]. Recently, the method of statistical mechanics has been applied to study a series of SCVP systems [25][26][27][28], and the equilibrium free energy and law of mass action were given in their explicit expressions.…”

Preparation and properties of highly branched poly(urethane-imide)-epoxy cross-linked copolymer

“…Hyperbranched architecture, which had their unique features and properties such as three-dimensional architecture, unentangled structure, low melting viscosity, good solubility, and large amounts of terminal functional groups, attracting a great deal of attention in scientific and industrial areas. [8] Comparing with conventional linear analogues, a small amount of hyperbranched architecture was sufficient for manifold increase in chemical resistance, durability and tensile strength. Until now, a lot of efforts had been devoted to synthesis highperformance highly branched polyurethane, but its properties could be further improved by modifying the terminal functional groups.…”

Statistical and thermodynamic properties of binary self-condensing vinyl polymerization

“…Since Fréchet and coworkers [1] synthesized hyperbranched polymers by self-condensing vinyl polymerization (SCVP), the relevant experimental and theoretical investigations have attracted intense interests [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. In the pure SCVP system, a monomer of AB * type is named as the inimer by Müller, Yan and Wulkow et al [2,3] because it possesses a vinyl group A and an active site B * .…”