Phase behavior of electrostatic complexes in systems containing polymers and surfactants in the presence of inorganic salts

• Grant number: 18/09099-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): August 01, 2018
• Effective date (End): February 28, 2022
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Watson Loh
• Grantee: Marcos Vinícius Aquino Queirós
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 15/25406-5 - Organizing matter: colloids formed by association of surfactants, polymers and nanoparticles, AP.TEM

Abstract

Complexation of polyelectrolytes with oppositely charged species in solution has been the focus of several researches regarding fundamental aspects and technological applications. These structures separate from the aqueous medium when they reach charge electroneutrality and can exist in two types of phases: the coacervates, characterized by being a concentrate, viscous liquid and the precipitates, which present as a fine solid. The components involved in the complexation are colloids ranging from homopolymers to block copolymers, polysaccharides, proteins, surfactants and inorganic nanoparticles. Its colloidal stability may depend on several factors, such as ionic strength, component charge density, polymer chain size, pH, etc. Furthermore, the formed aggregates may be outside the thermodynamic equilibrium, which implies that different preparation methodologies result in different colloidal properties, even if it is the same complex. Such behavior is still little understood and the lack of studies on the redispersion of these complexes induced by the presence of one of its own components serves as motivation for the development of this project. Based on this, it is intended to prepare binary complexes formed by the combination of polyelectrolytes and surfactant or other oppositely charged polyelectrolyte prepared by two different methods. Both homopolymers and block copolymers (ionic-neutral) will be used to monitor differences in the colloidal stability of the complexes. The main techniques employed to characterize the colloids will be light scattering, isothermal calorimetric titration and small angle X-ray scattering.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

AQUINO QUEIROS, MARCOS VINICIUS; LOH, WATSON. Preparation of Poly(acrylate)/Poly(diallyldimethylammonium) Coacervates without Small Counterions and Their Phase Behavior upon Salt Addition towards Poly-Ions Segregation. POLYMERS, v. 13, n. 14, JUL 2021. (15/25406-5, 18/09099-3)

AQUINO QUEIROS, MARCOS VINICIUS; LOH, WATSON. How to Predict the Order of Phase Separation of Polyelectrolyte Complexes and Their Miscibility. Journal of Physical Chemistry B, v. 126, n. 28, p. 12-pg., 2022-07-12. (15/25406-5, 18/09099-3)

OTONI, CAIO G.; QUEIROS, MARCOS V. A.; SABADINI, JULIA B.; ROJAS, ORLANDO J.; LOH, WATSON. Charge Matters: Electrostatic Complexation As a Green Approach to Assemble Advanced Functional Materials. ACS OMEGA, v. 5, n. 3, p. 1296-1304, JAN 28 2020. (17/07013-1, 15/25406-5, 18/09099-3, 18/25041-5, 19/00370-9)

AQUINO QUEIROS, MARCOS VINICIUS; LOH, WATSON. From Associative to Segregative Phase Separation: The Phase Behavior of Poly(acrylate)/Dodecyltrimethylammonium Complex Salts in the Presence of NaBr and NaCl. Journal of Physical Chemistry B, v. 125, n. 11, p. 2968-2975, MAR 25 2021. (18/09099-3, 15/25406-5)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

QUEIRÓS, Marcos Vinícius Aquino. Phase behavior of electrostatic complexes in systems containing polymers and surfactants in the presence of inorganic salts. 2022. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Química Campinas, SP.