Toward Homogeneous Nanostructured Polyaniline/Resin Blends

Abstract

The high interest in applications of conducting polymers, especially polyaniline (PANI), makes it important to overcome limitations for effective usage due to poor processability and solubility. One promising approach is to make blends of PANI in polymeric resins. However, in this approach other problems related to the difficulty of achieving a homogeneous PANI dispersion arise. The present article is focused on this general problem, and we discuss how the synthesis method, choice of dopant and solvent as well as interfacial energies influence the dispersibility. For this purpose, different synthesis methods and dopants have been employed to prepare nanostructures of polyaniline. Dynamic light scattering analysis of dispersions of the synthesized particles in several solvents was employed in order to understand how the choice of solvent affects PANI aggregation. Further information on this subject was achieved by scanning electron microscopy studies of PANI powders dried from various solutions. On the basis of these results, acetone was found to be a suitable dispersion medium for PANI. The polymer matrix used to make the blends in this work is a UV-curing solvent-free resin. Therefore, there is no low molecular weight liquid in the system to facilitate the mixing process and promote formation of homogeneous dispersions. Thus, a good compatibility of the components becomes crucial. For this reason, surface tension and contact angle measurements were utilized for characterizing the surface energy of the PANI particles and the polyester acrylate (PEA) resin, and also for calculating the interfacial energy between these two components that revealed good compatibility within the PANI/PEA blend. A novel technique, based on centrifugal sedimentation analysis, was employed in order to determine the PANI particle size in PEA resin, and high dispersion stability of the PANI/PEA blends was suggested by evaluation of the sedimentation data.

Long-term corrosion protection by a thin nano-composite coating

“…The static, advancing and receding water contact angles on the different surfaces are reported in Table 2. The PEA coating is weakly hydrophilic, consistent with earlier studies [31], and there is a low standard deviation in the contact angle value. Water slowly wets the TiO 2 surface over time, probably due to water penetrating the porous structure, and no equilibrium was found.…”

“…Following a procedure earlier described by Jafarzadeh et al [31] and Sababi et al [32] a UV-curing polyester acrylate (PEA) resin for primer coatings provided by Cytec was used. The formulation was based on chlorinated polyester resin which was diluted with hexanediol diacrylate.…”

Analysis of Particle Size Distributions of Quantum Dots: From Theory to Application

“…At this point it should be briefly mentioned that the same holds true for analytical centrifugation (AC) which works with lower gravitational fields but extends the measurement range to larger particle sizes (Detloff T. and Lerche D., 2008;Jafarzadeh S. et al, 2011;Krause B. et al, 2010;Walter J. et al, 2015c). Noteworthy, offline information from AUC, like for instance the optical properties of discrete QD fractions, could be implemented in evaluation routines based on UV/Vis spectroscopy.…”

Thermoresponsive polyaniline nanoparticles: Preparation, characterization, and their potential application in waterborne anticorrosion coatings

“…However, when applied at high temperature or in contact with an inorganic salt, it enhances the water-resisting ability of the epoxide coating. Since the PANI-NP/PVA-AI composite has a similar hydrophilicity to the epoxide coating at room temperature, it can be deduced that PANI-NP/PVA-AI composites can homogeneously disperse in the matrix of the epoxide coating, which is also a beneficial factor for the promotion of anticorrosion performance [29].…”

“…In the water-based anticorrosion coating systems, the waterborne PANI-NPs attract much interest not only because of the increasing requirements for environmental protection, but also because of their nanoscale dispersion in the matrix of waterborne coating polymers, which is a beneficial factor for the promotion of anticorrosion performance [29]. To the best of our knowledge, smart PANI-NPs have never been applied in water-based anticorrosion coating systems.…”