Apparent kinetic study of latex interpenetrating polymer networks P(ethyl acrylate)/P(styrene) and P(styrene)/P (ethyl acrylate) by two stage emulsion polymerization

P(ethyl acrylate)/P(styrene) (PEA/PS) latex interpenetrating polymer networks (LIPN) and P(styrene)/P (ethyl acrylate) (PS/PEA) LIPN were synthesized through two-stage emulsion polymerization and the apparent kinetics of polymerization was studied. Conversion versus time for LIPNs polymerization was investigated and rate of polymerization was calculated with the Arrhensius equation. It shows the polymerization of network I obeys the classical kinetic rules of emulsion polymerization showing an increasing-rate stage, a constant-rate stage and a decreasing-rate stage. But the polymerization of network II only appears a constant-rate stage and a decreasing-rate stage. It indicates that network II does not have a nucleus formation stage and the network 11 is formed on the basis of network 1. The apparent activation energies (E(as)) of LIPNPEA and LIPNPEA/PS in constant-rate period were 45.1 kJ/mol and 80.2 kJ/mol, respectively. However the E(as) of LIPNPS and LIPNPS/PEA were 42 kJ/mol and 44.3 kJ/mol. It demonstrates that the polymerization E(d) value of the network II is related to the properties of the seeded latex(network 1). (C) 2008 Elsevier B.V. All rights reserved.