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A facile approach of using halloysite nanotubes (HNTs) was proposed to address the durability performance demands of natural rubber (NR)/ethylene propylene diene monomer rubber (EPDM) blends and to protect them from the deleterious effects of the service environment including ozone, chemicals, abrasion, and cyclic loading. The introduction of HNTs substantially improved the stability of NR/EPDM when exposed to ozone (over fourfold enhancement with the addition of 5 phr HNTs). Moreover, the HNT-filled NR/EPDM vulcanizates offered approximately 66% reduction in the solvent-mediated swelling in comparison to the unfilled sample. Fatigue life studies showed that the HNT-reinforced NR/EPDM composite could withstand 30% more cycles to failure than the un-reinforced NR/EPDM blend. The effect of various HNT loading on the morphological, mechanical, physical, and rheological properties of nanocomposite vulcanizates based on NR/EPDM was also investigated. The morphological investigations revealed that the introduction of HNT into the NR/EPDM rubber matrix caused a rough morphology in fracture surface and a well-dispersed structure was obtained with the addition of up to 5 phr of HNTs. These findings were further supported by rheological, mechanical, and thermodynamical results.

In this work, we have successfully triggered the aqueous auto-redox reactions between reductive Ce(OH)3 and oxidative MnO4 - /Pd2+ ions to form PdO/Mn3 O4 /CeO2 (PMC) nanocomposites. PMC could spontaneously self-assemble into compact encapsulation on the surface of halloysite nanotubes (HNTs) to form the final one dimensional HNTs supported PMCs (HPMC). It is identified that there exists strong synergistic effects among the components of PdO, Mn3 O4 , and CeO2 , and hence HPMC could show excellent performance on photoassisted thermal catalytic CH4 combustion that its light-off temperature was sharply reduced to be 180 °C under visible light irradiation. Based on detailed studies, it is found that the catalytic reaction process well follows the classic MVK mechanism, and adsorption/activation of O2 into active oxygen species (O*) should be the rate-determining step for CH4 conversion.

A nanoarchitectural approach based on in situ formation of quantum dots (QDs) within/outside clay nanotubes was developed. Efficient and stable photocatalysts active under visible light were achieved with ruthenium-doped cadmium sulfide QDs templated on the surface of azine-modified halloysite nanotubes. The catalytic activity was tested in the hydrogen evolution reaction in aqueous electrolyte solutions under visible light. Ru doping enhanced the photocatalytic activity of CdS QDs thanks to better light absorption and electron-hole pair separation due to formation of a metal/semiconductor heterojunction. The S/Cd ratio was the major factor for the formation of stable nanoparticles on the surface of the azine-modified clay. A quantum yield of 9.3 % was reached by using Ru/CdS/halloysite containing 5.2 wt % of Cd doped with 0.1 wt % of Ru and an S/Cd ratio of unity. In vivo and in vitro studies on the CdS/halloysite hybrid demonstrated the absence of toxic effects in eukaryotic cells and nematodes in short-term tests, and thus they are promising photosensitive materials for multiple applications.

Regenerated cellulose (RC) bio-nanocomposite fibers reinforced with halloysite nanotubes (HNT) were fabricated through wet spinning technique via ionic liquid as a green solvent. Mechanical properties, water uptake, thermal stability, and cytocompatibility of the obtained fibers were examined. FTIR spectra indicated the uniform dispersion of HNT in the cellulose network. XRD analysis, together with FE-SEM images indicated that HNT was dispersed homogenously in the polymer. Moreover, mechanical and thermal stabilities of the nanocomposite fibers were notably increased through the addition of HNT. Eventually, human skin fibroblasts proliferation on nanocomposite fibers demonstrated good cyto-compatibility. These findings highlight the potential of HNT nanocomposite fibers for biological and biomedical applications.

The study's aim was to analyze the effects of different levels of halloysite (H) and zeolite (Z) in feed and pellets on the growth and meat quality in chickens; 500 Ross 308 broilers were assigned to five groups (1 g, control; 2-5 g, experimental). In Groups 2-5, different proportions of Z and H in feed (25:75 ratio; 0.5% to 2%) and pellet in kg/m2 (2, 0.650H; 3, 0.325H and 0.325Z; 4, 0.650Z; 5, 0.160H and 0.490Z) were used. Body weight was higher than 1 in all experimental groups, and carcass weight was higher, except for Group 2. The feed consumption was lower in Groups 3 and 5 than in Group 4. The breast muscle weight was higher in Group 3 than in the control group. In Groups 2, 3, and 5, the water holding capacity in the breast muscles was better than in Group 4 and in the leg muscles in Groups 3 and 4 than in Groups 1 and 5. Most of the tested characteristics indicate a beneficial effect of aluminosilicates in feed and litter on the growth and quality of meat.

Polar oxides are widely used as the cathodes to impede the shuttle effect in lithium-sulfur batteries, but suffer from the sluggish desorption and conversion of polysulfides due to too strong affinity of polysulfides on oxygen sites. Herein, employing halloysite as a model, an approach to overcome these shortcomings is proposed via engineering oxygen p-band center by loading titanium dioxide nanoparticles onto Si-O surface of halloysite. Using density functional theory calculations, it is predicted that electron transfer from titanium dioxide nanoparticles to interfacial O sites results in downshift of p-band center of O sites that promote desorption of polysulfides and the cleavage of Li-S and S-S, accelerating the conversion kinetics of polysulfides. The designed composite cathode material delivers outstanding electrochemical performance in Li-S batteries, outperforming the recently reported similar cathodes. The concept could provide valuable insight into the design of other catalysts for Li-S batteries and beyond.

Modified halloysite nanotubes (HNT-NH2 and HNT-COOH) were synthesized by a coupling reaction with 3-aminopropyltriethoxysilane and maleic anhydride from hydroxyl groups of neat halloysite nanotubes (HNTs). Successful attachment of functional groups onto HNTs was evaluated by Fourier transform infrared and thermogravimetric analysis. X ray diffraction was used to study the crystalline structure of scaffolds and the formation of intercalated structure as a result of improved dispersion and decreased agglomeration of modified nanoparticles. Neat HNT, HNT-NH2 , and HNT-COOH were subsequently introduced into polycaprolactone/Pluronic P123 (PCL/P123) electrospun substrate. Morphology, thermodynamics, mechanics, and biocompatibility of resulted electrospun nanocomposites were evaluated. Nanofibers containing modified HNTs showed excellent mechanical performance and thermal stability in comparison with those containing neat HNTs. homogeneous dispersion of the modified HNTs and strong interfacial adhesion between nanotubes and polymer matrix can be considered for mentioned improvements. Ultraviolet-visible spectrophotometer was used to study diphenhydramine hydrochloride and diclofenac sodium release from nanocomposites containing drug loaded modified and neat HNTs. Nanocomposites containing drug loaded HNT-COOH exhibited prolonged release of drug molecules in comparison with that of neat HNTs. MTT assay reveled that PCL/P123/modified HNTs nanocomposites provide a suitable platform for cell growth where PCL/P123/HNT-NH2 can facilitate cell attachment through electrostatic interactions between negatively charged phospholipids bilayer membrane of cells and positively charged HNT-NH2 embedded in PCL/P123 substrate. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1276-1287, 2018.