CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 16
·24799-24804
·
IF 3.83
Pengfei Pan,Xu Wang,Yaqi Ji,Wumei Dong,Lei Zhang,Ling Wang,Ming Zhang
A simple, efficient and low-cost method to synthesize zirconia nanopowders dispersed with graphene by wet ball milling was reported in this paper. The raw material for ball milling is cheap graphite powder rather than expensive graphene. Graphite powders were exfoliated into graphene nanosheets (GNSs) in the process of ball milling, as a result of strong shear forces and moderate impact forces between graphite powders, milling balls, and ZrO 2 nanoparticles . The mixed powders were milled for 3, 10, 20, 30, 40, and 50 h, respectively. Moreover, the morphology, composition and structure of the mixed powders milled were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy , Fourier transform infrared spectroscopy , and field emission transmission electron microscopy . Results showed that the graphite powders were exfoliated effectively, and the GNSs were dispersed uniformly in the zirconia simultaneously. The presence of zirconia nanoparticles significantly improved the efficiency of ball milling exfoliation.
研究领域:
材料科学
·
纳米技术
·
无机非金属材料
·
复合材料
✓ 已验证
DOI
高影响因子
DENTAL MATERIALS
·
2019
·
IF 4.44
Lei Li,Dan Li,Wenwen Zhao,Qing Cai,Gang Li,Yunhua Yu,Xiaoping Yang
Objective The object is to find an easy but efficient way to illustrate the in-situ dispersion of nano-scaled one-dimensional fillers in composite resins, and to correlate their dispersion status with the properties of composite resins. Methods Fluorescent europium-doped hydroxyapatite nanowires (HANW:Eu) were synthesized via the hydrothermal method . The HANW:Eu was mixed into Bis-GMA/TEGDMA (60/40, w/w) at different contents (1–5 wt.%), and different processing methods (kneading, grinding, stirring) were tested to achieve good dispersion of HANW:Eu with the aid of fluorescent imaging system. Then, the mixtures of HANW:Eu and barium glass powder (BaGP) were kneaded into resin at a fixed content (70 wt.%) while at different mixing ratios. In addition to the 3D fluorescent imaging, characterizations were carried out on mechanical properties , fractured surface, wear resistance and polymerization shrinkage, to correlate the composite properties of with the dispersion status of the incorporated HANW:Eu. Results By doping calcium with 5 mol.% of europium , the obtained HANW:Eu displayed strong fluorescence, which made the illustration of its in-situ dispersion status within composites being possible. And this helped to judge that kneading was more efficient to homogeneously disperse HANW:Eu than grinding and stirring. However, it was illustrated vividly that HANW:Eu aggregated severely when it was co-incorporated with BaGP into composites at the total content of 70 wt.%, which had not been previously revealed by other microscope observations. In comparison with composites containing 70 wt.% of BaGP, improvements in the mechanical properties of resulting composites were identified for the cases containing 3 wt.% of HANW and 67 wt.% of BaGP, however, their wear volume loss and the polymerization shrinkage did not decrease as expected due to the HANW aggregations. Significance The fluorescent filler prepared in this study provides a feasible strategy to illustrate the in-situ dispersion status of inorganic fillers, which provides guidance for the processing of composite resins.
研究领域:
材料科学
·
纳米技术
·
牙科材料
·
高分子科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2011
·
IF 3.068
Xiaoyin Zhang,Yuan Ren,Min Chen,Limin Wu
This paper presents a feasible and efficacious procedure to synthesize polystyrene/upconversion nanocrystals (PS/UCNCs) nanocomposite spheres with raspberry-like structure via an in situ dispersion polymerization technique. During this process, polyacrylic acid (PAA) as stabilizer plays the key role in adsorbing UCNCs, including NaYF 4 :Yb 3+ –Er 3+ , NaYF 4 :Yb 3+ –Tm 3+ and NaYF 4 :Yb 3+ –Ho 3+ onto the PS surfaces. TEM and SEM images confirmed the raspberry-like morphology of the obtained nanocomposite spheres. The effect of synthetic conditions, for instances, PAA amount, type and concentration of UCNCs on the structure and fluorescence of the PS/UCNCs nanocomposite spheres were studied in detail.
研究领域:
材料科学
·
纳米技术
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）