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This work presents the synthesis of crosslinked hexamethylene diisocyanate β‐cyclodextrins (HDI‐CDs) by reacting β‐cyclodextrin (β‐CD) with HDI as a crosslinking agent at different feed ratios. As a novel char‐forming agent, the HDI‐CDs are combined with ammonium polyphosphate (APP) and applied in polypropylene (PP) to form intumescent flame‐retardant composites. The structure of HDI‐CDs is characterized by Fourier transform infrared spectra (FTIR), 13C nuclear magnetic resonance spectroscopy, and nitrogen adsorption–desorption test. The thermogravimetric analysis (TGA) results indicate that HDI‐CDs have better char‐forming performance than β‐CD. FTIR spectra, X‐ray diffraction, and Raman spectra characterization demonstrate that the reaction between HDI‐CDs and APP contributes to the formation of a more stable char layer than β‐CD and APP. According to the results of TGA, scanning electron microscopy, limiting oxygen index (LOI), UL‐94, and X‐ray photoelectron spectroscopy test, when the crosslinking degree of HDI‐CDs is high enough (not less than β‐CD:HDI = 1:3.6), the PP/APP/HDI‐CDs composites can form a compact and dense char layer during combustion. Among all composites, PP/APP/HDI‐CD(4) shows the best flame‐retardant performance, which can pass the UL 94 V‐0 rating with an LOI value of 32.8% when the loading of flame retardants is 28 wt %. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48320. [ABSTRACT FROM AUTHOR]

Physical loss of stabilizers by migration and extraction accelerates the degradation of polymer materials. In this work, amino-containing nanosilica with anti-aging properties was prepared simply by the co-condensation of tetraethoxysilane and N -(2-aminoethyl)-3-aminoproply-trimethoxysilane (AEAPS). AEAPS was used to introduce amino groups into silica nanoparticles and to act as a catalyst in this process. The co-condensed nanosilica (CCS) showed agglomerate structure similar to the typical fumed nanosilica (FS). The amino groups were distributed both on the surface and inside the nanoparticles. HDPE/CCS and HDPE/FS composites were prepared by melt blending. Thermogravimetric analysis and oxidative induction time showed that CCS has effectively improved the thermo-oxidative stability of HDPE. In the long-term accelerated thermo-oxidative aging and UV aging tests, HDPE/CCS composite showed superior stability to neat HDPE and HDPE/FS composite. The results of infrared spectroscopy and electron paramagnetic resonance suggested that the HDPE/CCS composite manifested a special degradation mechanism involving the nucleophilic addition of amino groups to carbonyl species as well as the oxidation of amino groups on CCS by peroxides. The amino groups on CCS consumed carbonyl species and peroxides, and generated hydroxylamines and nitroxide radicals which were able to eliminate free radicals, thus restrained the degradation of HDPE. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the effectiveness of the Newman System model of care in the perioperative period for patients with endometrial cancer, to investigate the impact on psychological well-being, quality of life, and patient satisfaction., Methods: One hundred and eight patients with endometrial cancer who were treated in our hospital from January 2020 to January 2023 were selected as research subjects and were randomly divided into the control group (n=54) and the research group (n=54); the control group received conventional nursing care, and the research group added nursing care based on the conventional nursing care with Newman's systematic nursing care model including primary, secondary and tertiary care, comparing the psychological state score, quality of life score, coping style score, and satisfaction with nursing care of the two groups., Results: After the intervention, the anxiety self-assessment scale (SAS) and depression self-assessment scale (SDS) scores decreased in both groups, with the research group having lower scores than the control group (P < .05). After the intervention, all Oncology Quality of Life Core Questionnaire (QLQ-C30) scores increased in both groups, with the research group having higher scores than the control group (P < .05). After the intervention, avoidance and submission scores decreased in both groups, with the research group having lower scores than the control group (P < .05); coping scores increased in both groups, with the research group having higher scores than the control group (P < .05). Satisfaction with care was higher in the research group than in the control group (P < .05)., Conclusion: The Newman's system model of care is effective in the perioperative period of endometrial cancer, helping to reduce patients' negative emotions, optimize coping, improve quality of life and nursing satisfaction, and has great value in clinical application and promotion.