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Rubber/nanocellulose composite sheets improve tensile properties compared with neat rubber sheets, when nanocellulose materials are suitably compounded with rubber matrices. First, two oven‐dried nanocellulose materials containing different additive components were prepared from nanocellulose/water dispersions, and the oven‐dried nanocellulose‐containing materials were compounded with rubber sheets under high shear forces by using a two‐roll mill. The tensile moduli and strength of the rubber/nanocellulose composite sheets were clearly better than those of the rubber sheet prepared without nanocellulose, while the elongations at break were similar. Thin films were cut from the rubber/nanocellulose composite sheets, and their real‐time tensile deformation processes were observed by transmission electron microscopy (TEM) to understand the time‐dependent patterns of crack propagation, void formations, and fusion between cracks and voids in the composites during tensile deformation. TEM observations showed that the composite sheets consisted of individual rubber/nanocellulose clusters. Voids initially formed inside the rubber/nanocellulose clusters, propagated to form cracks, fused with other voids or secondary cracks. There were slight differences between the crack‐propagation patterns of the two rubber composites, probably because of differences in the morphologies, sizes, distributions, and structures of the rubber/nanocellulose clusters, and surface chemical structures of individual nanocellulose elements between the composites. [ABSTRACT FROM AUTHOR]

A resorcinol resin/water dispersion and a rubber latex are added to 1% 2,2,6,6,‐tetramethylpyperidine‐1‐oxyl (TEMPO)‐oxidized cellulose nanofibers (TEMPO‐CNFs) dispersed in water, followed by oven drying at 40 °C for 20 h to prepare a dried TEMPO‐CNF/resorcinol resin/latex rubber (DTRL) mixture with a weight ratio of 1/0.5/3. DTRL is then added to a nitrile‐butadiene rubber (NBR) or a carboxy group‐containing NBR (X‐NBR) sheet, and the mixture is kneaded by a two‐roll mill at 20–30 °C with high shear forces. The tensile strength and Young's modulus of the crosslinked DTRL/rubber composite sheets remarkably increased from 10 and 12 MPa, respectively, for the reference sheet to 24 and 82 MPa, respectively, for the DTRL/rubber composite sheets containing ≈10 vol% TEMPO‐CNFs. Scanning electron microscopy revealed that no TEMPO‐CNF agglomerates are present in the DTRL/rubber composite sheets. The tensile properties of the composite sheets are the best when a X‐NBR sheet and NBR latex are used as the matrix rubber and latex in DTRL preparation, respectively. When water‐extracted DTRL (WDTRL, mass recovery ratio ≈94%) is used in place of DTRL, the WDTRL/rubber composite sheets show sufficient water resistance, while the tensile properties are almost the same as those of the DTRL/rubber composite sheets. [ABSTRACT FROM AUTHOR]

Polyamide 66 (PA66) nanocomposites were prepared by compounding carbon nanotubes (CNTs) using an elastic high‐shear kneading method, and the mechanism to understand their excellent properties was verified. In addition, we developed a microwave heat treatment that increases toughness quickly and at low cost. By combining 6.6 vol% or more of CNTs, PA66 with improved mechanical properties, such as higher elastic modulus and yield strength, was achieved, making it possible to obtain a composite having excellent high‐temperature characteristics that does not melt even at a temperature above the melting point. These effects appeared to be due to defibration of CNT aggregates and isolation and dispersion in PA66. A lamellar crystal of PA66 grows around the CNT, forming an interphase. The higher performance appeared to be attributable to a continuous three‐dimensional structure in which CNTs are bound via the interphase, and the improvement of the elastic modulus of the composite material was tentatively ascribed to a Halpin‐Tsai model in which the size of the unit cell of the three‐dimensional structure is introduced. The resulting CNT/PA66 composite materials are superior not only in performance but also in price. [ABSTRACT FROM AUTHOR]

Keywords: asthma; eosinophils; virus EN asthma eosinophils virus 1805 1809 5 07/14/20 20200701 NES 200701 Acute respiratory infections including rhinovirus (RV) infections are a major cause of asthma exacerbations. Along with increased CDHR3 expression on the cell surface, transfection with CDHR3-Y SB 529 sb also increased eosinophil adhesion compared to CDHR3-C SB 529 sb or the negative control (Figure 2A). These findings suggest that the difference in eosinophil adhesion was due to the level of surface expression of CDHR3 protein, but not due to the different ability of the CDHR3 variants to induce eosinophil adhesion. Given the close association between eosinophilic inflammation and asthma exacerbation, CDHR3-Y SB 529 sb could promote eosinophil adhesion and proinflammatory functions linked to asthma exacerbations. [Extracted from the article]