A self-doped polyaniline derivative obtained by electrochemical copolymerization of aminoterephthalic acid and aniline

[EN] The electrochemical copolymerization of aminoterephthalic acid and aniline can be achieved to yield a self-doped material showing electroactivity at physiological pH. The present study focusses on the management of the synthesis conditions to obtain a true copolymerization product and to control the relative amount of both comonomers eventually incorporated to the copolymer chain. Both, in situ FTIR spectroscopy and ex situ XPS techniques proved the successful incorporation of aminoterephthalic acid and, in parallel to other polyaniline parent derivatives, revealed the existence of redox transformations involving leucoemeraldine-emeraldine-pernigraniline transitions. The use of a high inversion potential (1.4¿V/RHE) during electro-copolymerization resulted in a material enriched in aminoterephthalic acid fraction with respect to aniline, while this last component is favored at lower potentials. The pH behavior of copolymers in combination with in situ FTIR results strongly suggested that a larger content of aminoterephthalic acid (such as that obtained after deposition at 1.4¿V) do not ensure an extensive self-doping process because a significant fraction of those carboxylic moieties remain inactive during the redox transformation. Instead, low inversion potentials are preferred to obtain a material with less defects and thoroughly electroactive at physiological pH.Financial support from the Spanish Ministerio de Economia y Competitividad and FEDER funds (MAT2016-76595-R) is gratefully acknowledged. S. Dhkili thanks the Ministry of Higher Education and Scientific Research of Tunisia for funding her stay at the University of Alicante.Dkhili, S.; López-Bernabeu, S.; Huerta, F.; Montilla-Jiménez, F.; Besbes-Hentati, S.; Morallón, E. (2018). A self-doped polyaniline derivative obtained by electrochemical copolymerization of aminoterephthalic acid and aniline. Synthetic Metals. 245:61-66. https://doi.org/10.1016/j.synthmet.2018.08.005S616624

Critical barriers to environmental management system implementation in the Nigerian construction industry

This is an accepted manuscript of an article published by Springer in Environmental Management, available online: https://doi.org/10.1007/s00267-021-01473-y The accepted version of the publication may differ from the final published version.The impact of different hazardous substances of the construction industry being released to the environment is alarming. This constitutes an adverse effect on the quality of life of construction workers and the populace at large. To reduce this menace, Environmental Management System (EMS) was put in place. Meanwhile, the implementation of EMS in the Nigerian construction industry (NCI) is not certain. This study, therefore, investigated the barriers to EMS implementation in the NCI to group them into a smaller form, i.e., fewer numbers. A questionnaire survey was developed and administered to construction professionals in Nigeria using a purposive sampling technique. The retrieved 106 copies of the questionnaires were subjected to both descriptive and inferential statistics such as mean score, standard deviation, analysis of variance test, post hoc test and exploratory factor analysis. An exploratory factor analysis was conducted three times to identify the critical barriers to EMS implementation in the NCI. The study findings reveal three main categories of barriers affecting EMS implementation, namely; (1) knowledge barrier; (2) process barrier; and (3) culture and management barrier. The study concluded that the three factors indicate the major cardinal barriers that could describe the impediment of EMS in the NCI. It was recommended that the training of construction professionals is important to enhance improvement culture in the NCI