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This study aims to investigate the behavior of the green biomass-derived copper (lignin/silica/fatty acids) complex, copper lignin/silica/fatty acids (Cu-LSF) complex, when incorporated into the nonpolar ethylene propylene diene (EPDFM) rubber matrix, focusing on its reinforcing and antioxidant effect on the resulting EPDM composites.

The structure of the prepared EPDM composites was confirmed by Fourier-transform infrared spectroscopy, and the dispersion of the additive fillers and antioxidants in the EPDM matrix was investigated using scanning electron microscopy. Also, the rheometric characteristics, mechanical properties, swelling behavior and thermal gravimetric analysis of all the prepared EPDM composites were explored as well.

Results revealed that the Cu-LSF complex dispersed well in the nonpolar EPDM rubber matrix, in thepresence of coupling system, with enhanced Cu-LSF-rubber interactions and increased cross-linking density, which reflected on the improved rheological and mechanical properties of the resulting EPDM composites. From the various investigations performed in the current study, the authors can suggest 7–11 phr is the optimal effective concentration of Cu-LSF complex loading. Interestingly, EPDM composites containing Cu-LSF complex showed better antiaging performance, thermal stability and fluid resistance, when compared with those containing the commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline and N-isopropyl-N’-phenyl-p-phenylenediamine). These findings are in good agreement with our previous study on polar nitrile butadiene rubber.

The current study suggests the green biomass-derived Cu-LSF complex to be a promising low-cost and environmentally safe alternative filler and antioxidant to the hazardous commercial ones.

The purpose of this study is to frame the dimensions of the external institutional environment, namely, cultural-cognitive, normative and regulative dimensions as the main actors in the organisational field. More precisely, Libyan commercial banks have been identified as empirical evidence, to identify constraints of the institutional environment governing the behaviour and decision-making of commercial banks, when adopting Islamic financial transactions.

A questionnaire has been designed for 14 Libyan commercial banks which is distributed to the Board of Directors, managers, directors of departments, and personnel. The exploratory factor analysis (EFA) and the measurement model by using the first-order and second-order confirmatory factor analysis (CFA) have been applied as essential steps to embody the conceptual framework and test the research hypotheses.

The results of the EFA indicated sufficient correlation among the dimensions of the external environment. The CFA supported this study’s hypotheses. The modelling showed that the cultural-cognitive, normative and regulative dimensions are institutional constraints impeding Libyan commercial banks’ adoption of Islamic financial transactions. Interestingly, the findings of the CFA align with the EFA findings in supporting the conceptual framework of the research. They portrayed that the cultural-cognitive dimension has been identified by explicit and implicit cognition.

This study systematically embodies the dimensions of the external institutional environment, namely, cultural-cognitive, normative and regulative dimensions, as the main factors in the organisational field to be conceptually rich lenses to investigate social considerations to reinforce institutional thought broadly. The results of this study were consistent with extant Islamic financial literature, reflecting symmetry and similarity across commercial banks, particularly at the first stage of adopting Islamic financial transactions.

The aim of the present paper to compare the cleaning treatments of paper samples exposed to artificial aging, toluene and isopropyl alcohol gel in cleaning wax stains.

In total, paper samples were made from wood pulp. They had a deterioration phenomenon represented in the stains of the paraffin wax, so two types of cleaning were used: A traditional method using a toluene solution and another new method using isopropanol gel by a cotton swap in a circular movement until the completion of the cleaning process. Then, all paper samples were treated with toluene and isopropanol to handle the second artificial aging and detect how the samples were affected by artificial aging. For identifying the efficacy of these materials in removing paraffin wax stains, a range of examinations and analyses were used, such as universal serial bus, scanning electron microscope, infrared analysis (IR), pH analysis, color change analysis. Moreover, these results were compared with the standard sample’s results.

The results of examinations and analyses proved that the use of toluene affected the paper samples. Their effects were twice as weak, fragile and degraded paper fibers compared to isopropanol gel. Therefore, the isopropanol gel is preferred for paper cleaning to the toluene solution.

This paper highlights the efficiency of isopropyl alcohol gel in cleaning wax stains from historical paper supports.