Heteroflocculation studies of colloidal poly(N-isoproprylacrylamide) microgels with polystyrene latex particles: Effect of particle size, temperature and surface charge.
Snowden, Martin J., Gracia, Louise H. and Nur, Hani (2008) Heteroflocculation studies of colloidal poly(N-isoproprylacrylamide) microgels with polystyrene latex particles: Effect of particle size, temperature and surface charge. In: New frontiers in colloidal science: a celebration of the career of Simon Vincent. Royal Society of Chemistry Publishing, pp. 148-165. ISBN 978-1-84755-843-5, 978-0-85404-113-8 (print)Full text not available from this repository.
The heteroaggregation behaviour of thermosensitive cationic poly(N-isopropylacrylamide)[poly(NIPAM)] microgels and anionic polystyrene (PS) latex particles has been investigated with respect to particle size, surface charge, deformability of the particle, temperature and concentration. Microgels and PS latex particles have been characterised. Turbidimetric analysis and scanning electron microscopy have been employed to determine the state of aggregation of mixtures of the two types of particles.
PS latex particles of varying size (100–800 nm) have been studied in mixtures with two cationic microgels. Results show that the ionic interaction between oppositely charged deformable and non-deformable particles can be manipulated by changing the particle size, concentration and temperature of the particles in the mixture. It has been found that aggregation is induced in the mixtures containing the largest of the PS latex particles by the lowest concentration of microgel. It is also reported that the larger the latex the less is the influence of temperature on the stability of the mixed particulate system.
The heteroflocculation/aggregation behaviour is influenced by the relative concentration of the two oppositely charged species. The change from a dispersed to an aggregated system is most likely continuous and the relative concentration at which aggregation begins to occur is somewhere between a 1 : 1 ratio and 10 : 1 excess of the cationic microgel. This concentration effect can be used to initiate aggregation at temperatures below the volume phase transition temperature of the poly(NIPAM) microgels.
|Item Type:||Book Section|
|Additional Information:|| Chapter 8.  Book offers a summary of the career of Brian Vincent and an autobiographical summary of his impact on the field. Some of the topics covered include: The Adsorption of Small, Negative Particles onto Large Positive Particles; Polymer Chemistry, Hypervelocity Physics and the CASSINI Space Mission; The BV Droplets Downunder: From Model Emulsions to Drug Delivery; Polymers and Surfactants at Interfaces; Controlled Release as Desorption from Porous Polymeric Systems; Characterisation and Application of Colloidal Micorogels; Surface Modification. Brian Vincent is a recognised expert in the field, and will have a specific appeal to colloid scientists both in academia and industry.  A two-day conference, ‘New Frontiers in Colloid Science’, was held at Lord’s Cricket Ground in London on 1-2 April 2008. This meeting was jointly organised by the RSC Colloid and Interface Science Group and the SCI Colloid and Surface Chemistry Group to celebrate the career of Professor Brian Vincent. http://www.soci.org/News/Colloids-Prof-Vincent-Career-Celebration  Conference paper for this book chapter is available at http://www.soci.org/News/Colloids-Prof-Vincent-papers.aspx.|
|Uncontrolled Keywords:||heteroflocculation, microgels, colloidal poly(N-isoproprylacrylamide)|
|Subjects:||Q Science > QD Chemistry|
|School / Department / Research Groups:||School of Science|
School of Science > Department of Pharmaceutical, Chemical & Environmental Sciences
|Last Modified:||30 Aug 2012 11:47|
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