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The potential of nanocomposite membranes (NCMs) prepared by the sodium alginate polymer and embedded with synthesized zeolitic imidazole framework-8 (ZIF-8) as fillers having microporous structure in the application of separation of gaseous mixture generated by the process of methane reforming was assessed. ZIF-8 crystals were created through hydrothermal synthesis, with sizes varying from 50 to 70 nm. NCMs were prepared with a 15% filler loading, i.e., synthesized ZIF-8. NCMs (ZIF-8) having H2 permeability of 28 Barrer and H2/CH4 selectivity of 125 outperformed neat polymer membranes in terms of separation performance at ambient temperature and 4 kg/cm2 pressure. The purity of H2 increased to as high as 95% among the measured values. The NCMs did not, however, outperform a neat polymer membrane in terms of their ability to separate mixtures of gases. Moreover, the combination of ZIF-8 as a filler with sodium alginate was new and had not been reported previously. As a result, it is worthwhile to investigate. [ABSTRACT FROM AUTHOR]

Global climate change is already affecting the environment, as glaciers are receding, ice on rivers and lakes is melting, plant and animal range's have altering, and trees are blooming early. Therefore, focus has shifted towards sustainable materials. There is a growing desire for materials that have a unique combination of qualities that metals, polymers, and other materials cannot provide, therefore scientists are turning their focus to green composites. Green composites offer a wide range of uses in automotive, aerospace, and marine applications. Composites are multiphase resources with separate interfaces that contain chemically different materials. Composites are made up of a variety of materials that are distinct in nature, and they give a set of desirable features that are superior to those of their predecessors or parents. Natural fibers are less expensive, more readily available, rust-resistant, plentiful, nontoxic, and safe for human skin, eyes, and respiratory systems. Green composites are created by combining renewable fibers with polymers (matrix) to create a new class of composites known as "green composites." This review includes studies on various animal-based fibers and their applications. In this article, recent advancements in the field of these fibers and their composites of fibers are also discussed. The physical, chemical, and mechanical properties are also discussed in this paper. Moreover, the benefits and drawbacks of using these fibers are also discussed in detail. Finally, the paper gives an outline of the topic. The results from composites constructed from each fiber are provided, along with appropriate references for more in-depth analysis studies. This review is specially performed to strengthen the knowledge bank of the young researchers working in the field of natural composites. [ABSTRACT FROM AUTHOR]

Surfactants are ubiquitous materials that are used in diverse formulations of various products. For instance, they improve the formulation of gel by improving its wetting and rheological properties. Here, we describe the effects of anionic surfactants on an anesthetic drug, tetracaine hydrochloride (TCH), in NaCl solution with tensiometry and UV–visible techniques. Various micellar, interfacial, and thermodynamic parameters were estimated. The outputs were examined by using different theoretical models to attain a profound knowledge of drug–surfactant mixtures. The presence of attractive interactions among drug and surfactant monomers (synergism) in mixed micelle was inferred. However, it was found that sodium dodecyl sulfate (SDS) showed greater interactions with the drug in comparison to sodium lauryl sarcosine (SLS). The binding of the drug with surfactants was monitored with a spectroscopic technique (UV–visible spectra). The results of this study could help optimize the compositions of these mixed aggregates and find the synergism between monomers of different used amphiphiles. [ABSTRACT FROM AUTHOR]

In this paper, the interaction of imipramine hydrochloride (IMP, antidepressant drug) and a non-ionic surfactant Triton X-100 (TX-100) mixture in five different ratios through the tensiometric method in different solvents (aqueous/0.050 mol·kg−1 aqueous NaCl/0.250 mol·kg−1 aqueous urea (U)) were examined thoroughly at a temperature of 298 K. UV–Visible studies in an aqueous system of IMP + TX-100 mixtures were also investigated and discussed in detail. The pure (IMP and TX-100) along with the mixtures' critical micelle concentration (cmc) were assessed by a tensiometric technique. The obtained deviation of the mixtures' cmc values from their ideal values revealed the nonideal behavior of IMP + TX-100 mixtures amongst IMP and TX-100. Compared to aqueous systems, in the presence of aqueous NaCl, several changes in micelles/mixed micelles occurred, and hence a synergism/attractive interaction amongst components was found increased while in the existence of U, the synergism/attractive interaction between them decreased. The evaluated interaction parameter (βRb) value of mixed micelles showed the attractive or synergism between the IMP and TX-100. Various evaluated thermodynamic parameters in an aqueous system showed that the mixed micellization of the IMP + TX-100 mixture was an entropically spontaneous phenomenon, although the existence of salt in all studied systems can somewhat increase the spontaneity of the micellization process and in the aqueous U system, the spontaneity of the micellization process decreased. In an aqueous system, the interaction between IMP and TX-100 was also confirmed by UV–Visible study. [ABSTRACT FROM AUTHOR]

In drug delivery, surfactants are used to reduce side effects and to increase drug efficiency. The present work aimed to study the interaction of diphenhydramine hydrochloride (anti-allergic drug) with TX–45 (non-ionic surfactant) in the absence and presence of ionic liquid (1-hexyl-3-methylimidazolium chloride). The physicochemical parameters were estimated by the surface tension measurement. Various theoretical models (Clint, Rubingh, Motomura, and Maeda) were applied to determine the attractive behavior between drug and surfactant mixtures at the surface and in bulk. The drug and surfactant mixtures exhibit synergistic behavior in the absence and presence of ionic liquid. Several energetic parameters were also estimated with the assistance of regular solution approximation and pseudo phase separation model that indicate micelle formation and adsorption of surfactant at the surface is thermodynamically advantageous. The morphology of pure and mixture of amphiphiles has been estimated by the Tanford and Israelachvili theories. UV-visible spectroscopy was used to quantify the attractive behavior of the drug with surfactant with the help of a binding constant (K). [ABSTRACT FROM AUTHOR]

The focus of the present work is to evaluate the interactions of an anti-allergic drug (diphenhydramine hydrochloride, DPH) with anionic (sodium dodecyl sulfate, SDS) and cationic (cetylpyridinium chloride, CPC) surfactants in the aqueous medium. The mixed micellization behavior and surface properties of drug-surfactant mixtures have been examined by surface tension measurements. Various theoretical approaches were applied to explore the synergistic or non-ideal behavior of the current mixed systems. Furthermore, the binding studies of drug with surfactants have been elaborated by UV–visible spectroscopy. Benesi–Hildebrand (B-H) theory was used to compute stoichiometric ratio, binding constant, and free energy change for the drug-surfactant mixtures. The outputs are deliberated taking into consideration the use of surfactants as capable drug delivery agents for DPH and hence advance bioavailability. [ABSTRACT FROM AUTHOR]