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The application of cashew gum, in particular the one which is abundant in northeastern Brazil, remains limited to the foods and pharmaceutics industry. In attempting to obtain further potentialities of the cashew gum (CG), its electrical applicability needs to be explored. To this end, the CG is incorporated in blends based on PANI to make an innovative thin self-sustainable blend films (PACG) comprising PANI and CG. The blend films were fabricated by adding the CG in the synthesis process of the polyaniline, and they were prepared by the standard "casting" method. The film materials were blending in three different weight ratios (99:1), (95:5) and (80:20). We also fabricated the only PANI film. As PANI has its conductivity enhanced by doping process, the blends and PANI films were doped by using sulfuric acid at 0.05 and 0.1 mol L−1 concentrations. The characterization of the films was carried out by FTIR spectroscopy, thermal analyses and electrical measurements. The FTIR results exhibited the occurrence of a weak and secondary chemical interaction between PANI and CG. Once there was no appearance of new bands, the profile of the FTIR curves was maintained for the blends and no significant shifts were identified for the maximum frequency of bands. The thermal analysis measurements revealed alteration at the thermal stability temperature of blends due to the doping process and indicated that the thermal profile of the constituent materials (PANI and CG) was preserved in the blends. The electrical studies showed that the undoped blend films exhibited a low level of conductivity as the amount of gum increased. On the other hand, the doped films reached a high level of conductivity in comparison with PANI films and the more the amount of CG in the blend the more is its conductivity. For PACG with 20% of gum, σ increased by a factor of 106, whereas in PANI film, it increased by 104 at the 0.1 mol L−1 doped level. These results point to the possibility of using this sort of blend based on polyaniline and cashew gum as an innovative conductive polymer once it exhibits acceptable electrical, structural and thermal properties. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study the composites which are commonly called NR/CB/Leather were developed in order to apply them as antistatic flooring and coating. They were developed using vulcanized natural rubber, carbon black to add an electric conduction property and industrial leather waste. The leather industrial waste was micronized and added to the rubber matrix in proportions of 60 and 80 phr using an opened mixing cylinder according to ASTM D 3182 standard. The composites were exposed to the sanitizing agents, (i) bleach and (ii) disinfectant, aiming to simulate a real cleaning context, and to meet the health standards of the Brazilian Ministry of health. Physical-chemical and microbiological evaluations were carried out to determine the structural and chemical stabilities of the composites. After this, low water absorption level (<1.5%), immobilization and low chromium oxide level (<1.5), pH within the neutrality rate and an excellent resistance to microbiological contamination were identified for the composites. Thus, from a physical-chemical perspective, the composites NR/CB/Leather displayed suitable properties and potential for application as antistatic flooring and coatings. Besides using leather industrial waste in their production, their manufacture can boost this industrial sector economically and, consequently, promote a reduction in environmental impact. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43618. [ABSTRACT FROM AUTHOR]