Agglomeration of distributed particles is the main problem in polymer composites reinforced with such particles. It leads to a decrease in mechanical performance and its poor reproducibility. Thus, development of methods to address the agglomeration of particles is relevant. Evaluation of the size and concentration of agglomerates is required to select a method to address agglomeration. The paper analyzes aluminum oxide particles agglomeration in particles-reinforced polymethyl methacrylate (PMMA) composites. Quantitative parameters of polystyrene-coated aluminum oxide particles agglomerates are obtained for the first time in this article. Unlike uncoated aluminum oxide particles, when coated aluminum oxide particles are used, agglomerates concentration in polymer composites decreases approx. 10 times. It demonstrates that modification of submicron particles by a polymer coating decreases the number of agglomerates in the polymer composite. The use of transmittance and opacity values to estimate particles agglomerates is reasonable in this article. It is shown that the difference in optical performance of specimens reinforced with coated and the original particles is related to the number and average size of agglomerates in the specimens. For example, when the concentration exceeds 0.2%, transmittance values for the specimens reinforced with coated particles are greater than the ones for the specimens reinforced with the original particles.

Synthesis and application of nanostructured materials applicable in the assembly of electrochemical sensors is one of the important trends in material sciences and analytical chemistry. In this work, we have proposed and implemented simple non-template method for assembling nanofibers from the polyaniline ultrasonicated with phenyliminophenothiazine in aqueous media. Two-step procedure including association with emeraldine dispersion and reorganization under ultrasonication led to formation of nanofibrillar structures with average diameter of 20 nm. UV-spectroscopy confirms that association of phenyliminophenothiazine and polyaniline in acidic medium resulted in an intense absorption band at 900–910 nm due to donor-acceptor interaction between the reactants. The material combined emeraldine charge transmission with redox activity of phenyliminophenothiazine was found promising for electrochemical sensing. It was confirmed by comparison of characteristics of appropriate solid-contact sensors based on emeraldine and phenyliminophenothiazine toward Fe(III) ions, ascorbic acid and hydroquinone. In all the cases, the use of phenyliminophenothiazine results in a wider concentration range and more reproducible signal against characteristics of similar sensor based on polyaniline. The applicability of the sensor was confirmed by determination of iron content in commercial medication.

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The polyaniline (PANI) films filled by carbon particles can demonstrate the conductivity increasing. The carbon particles uniform distribution in the PANI films can be received by their contemporaneously formation in the atmospheric pressure plasma. The films properties produced from aniline contemporaneously with carbon particles in the atmospheric pressure plasma are considered in that paper. The energy density threshold (~ 30 mJ/m) of gas discharge starting from which it is possible to obtain a continuous film filled with agglomerates of carbon particles was defined. It was showing that the such films has the amorphous morphology. It was defined that the carbon particles agglomerates in the PANI films. The carbon particles agglomerates concentration in the PANI films is about ~(4 – 7)·104 1/cm2 and slowly depends on the energy density. So the conductivity of that films cant be increasing by this particles. It was shown that the films moisture saturation is the main reason of them conductivity increasing. It was shown that the films creep are decreases and the hardness increases when the gas discharge energy density increases. Its because the crosslinks number is growth in the samples. The molecular weight of PANI films is low, so the Martens hardness value has low-level.

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