Abstract
Polyelectrolyte complexes (PECs) were prepared by structural uniform and strongly charged cationic and anionic modified alternating maleic anhydride copolymers. The hydrophobicity of the polyelectrolytes was changed by the comonomers (ethylene, isobutylene and styrene). Additionally, the n−/n+ ratio of the molar charges of the polyelectrolytes and the procedure of formation were varied. The colloidal stability of the systems and the size, shape, and structure of the PEC particles were investigated by turbidimetry, dynamic light scattering (DLS) and atomic force microscopy (AFM). Dynamic light scattering indicates that beside large PEC particle aggregates distinct smaller particles were formed by the copolymers which have the highest hydrophobicity (styrene). These findings could be proved by AFM. Fractal dimension (D), root mean square (RMS) roughness and the surface profiles of the PEC particles adsorbed on mica allow the following conclusions: the higher the hydrophobicity of the polyelectrolytes, the broader is the particle size distribution and the minor is the swelling of the PEC particles. Hence, the most compact particles are formed with the very hydrophobic copolymer.
Highlights
In the last decades, nanoparticles have become more important due to their potential applications in many areas of industry, biotechnology and medicine.Special types of such particles are the polyelectrolyte complex (PECs), which are formed by strong electrostatic interactions between oppositely charged polyelectrolytes (PELs) in aqueous solution.Extensive studies have been performed by several authors on the different types of Polyelectrolyte complexes (PECs) that can be formed: insoluble and amorphous polyelectrolyte complexes (PEC), soluble PECs and stable colloidal dispersions
If we compare the PECs of the same preparation procedure and n-/n+ ratio as a function of the comonomere of the PC and PA, respectively, we find a minimal increase of the turbidity with higher hydrophobicity of the PELs in most cases
As we could not decide between an artifact or a particle, we investigated the PEC particles by means of atomic force microscopy
Summary
Nanoparticles have become more important due to their potential applications in many areas of industry, biotechnology and medicine.Special types of such particles are the polyelectrolyte complex (PECs), which are formed by strong electrostatic interactions between oppositely charged polyelectrolytes (PELs) in aqueous solution.Extensive studies have been performed by several authors on the different types of PECs that can be formed: insoluble and amorphous PECs, soluble PECs and stable colloidal dispersions. Nanoparticles have become more important due to their potential applications in many areas of industry, biotechnology and medicine. Special types of such particles are the polyelectrolyte complex (PECs), which are formed by strong electrostatic interactions between oppositely charged polyelectrolytes (PELs) in aqueous solution. Extensive studies have been performed by several authors on the different types of PECs that can be formed: insoluble and amorphous PECs, soluble PECs and stable colloidal dispersions. The type of nanoparticle that a PEC belongs to depends on many different parameters such as pH, ionic strength, the molar ratio of the mixed anionic to cationic charges of the PELs (n−/n+) and on the polymer concentration CP in the solution. The current knowledge of PECs has been reviewed by different authors [1,2,3,4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
