Pullulan-Based Polymer Surfactants for Vinyl Acetate Miniemulsion Polymerization: Kinetics and Colloidal Stability Investigations

• Published in: Macromolecular chemistry and physics Vol. 216; no. 18; pp. 1879 - 1887
• Main Authors: Belbekhouche, Sabrina, Picton, Luc, Le Cerf, Didier, Hamaide, Thierry
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.09.2015; Wiley Subscription Services, Inc; Wiley-VCH Verlag
• Subjects: Block copolymers; Chain reactions; Chemical Sciences; colloidal stability; Colloids; kinetics; Material chemistry; miniemulsion polymerization; Molecular weight; Polymerization; Polymers; pullulan-based polymer surfactants; Stability; Stabilization; Surfactants; Vinyl acetate; colloidal stability; kinetics; pullulan-based polymer surfactants; miniemulsion polymerization
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.201500130

Various pullulan‐b‐Jeffamine block copolymers (Jeffamine is a PEO‐b‐PPO copolymer (PEO = poly(ethylene oxide), PPO = poly(propylene oxide)) are used as surfactants for vinyl acetate miniemulsion polymerization. Their influence on the kinetics, average molecular weights and colloidal stability, is compared with that of Pluronic F68, when using either organosoluble or hydrosoluble initiators. In the first case, conversions and molecular weights are not affected by the polymer surfactant, in contrast to what is observed when using the hydrosoluble system, that may be due to a reaction between the incoming radicals and the sugar units of the pullulan chain. Long‐term colloidal stability between 4 °C and 40 °C over more than 4 months is observed and is not affected by the addition of salts when using pullulan‐based surfactant. Pullulan‐b‐Jeffamine block copolymers are versatile bio‐based polymer surfactants for an efficient stabilization of vinyl acetate miniemulsion polymerization. They enable a long‐term colloidal stabilization, even in the presence of salts. Hydrophobic initiators are required in order to avoid possible reaction between incoming radicals and sugar units of the pullulan chain, which affects the kinetics and polymer average molecular weights.