Modeling Polystyrene Homogeneous‐Coagulative Nucleation in Pickering Emulsion Polymerization. Issue 6 (28th July 2022)

• Record Type: Journal Article
• Authors: Brunier, Barthélémy; Chevalier, Yves; Bourgeat‐Lami, Elodie; Sheibat‐Othman, Nida
• Other Names: Soares João B. P. guestEditor.
• Is Part Of: Macromolecular reaction engineering. Volume 16:Issue 6(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-28
• Subjects: homogeneous coagulative nucleation -- hectorite clay platelets -- pickering surfactant‐free emulsion polymerization -- population balance modeling; Polymers -- Periodicals; Polymerization -- Periodicals; Reaction mechanisms (Chemistry) -- Periodicals; Electronic journals; 547.705
• DOI: 10.1002/mren.202200016
• Languages: English
• ISSNs: 1862-832X

Abstract

Abstract: Investigation of particle nucleation in surfactant‐free emulsion polymerization of styrene using Laponite clay as Pickering stabilizer is considered. The effective number of clay platelets contributing to the surface charge of the polymer particles is calculated, and used to estimate their stabilizing efficiency. A coagulative nucleation mechanism is proposed and the coagulation coefficient is calculated using the Derjaguin–Landau–Verwey–Overbeek theory. The Hamaker constant involved in the attractive potential of the clay‐polymer composite particles is measured experimentally. The model is found to fit the experimental data in terms of the number of nucleated particles and the nucleation period. The effective number of clay platelets contributing to the surface charge is found higher than the number of platelets allowing full polymer latex surface coverage at the end of nucleation. Moreover, efficient stabilization against coagulation requires almost complete coverage. Abstract : A model is proposed to describe particle nucleation in Pickering emulsion polymerization. Coagulative homogeneous nucleation is coupled with a Derjaguin–Landau–Verwey–Overbeek‐based coagulation kernel. It is found that particle nucleation continues until the clay platelets cover the full particle surface. In case double layers of platelets are formed, only clay platelets in contact with water contribute to particle stabilization.