MACROMOLECULAR CHEMISTRY AND PHYSICS
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2024
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IF 2.5
Yuntao Fu,Haichao Meng,Fenglin Wang,Huawei Zou,Yinfu Luo,Mei Liang,Peng Xie
Polyimide (PI) hollow microspheres possess lightweight and excellent thermal resistance, which are widely used in microreactors, catalysis, adsorption separation, high-temperature insulation, and so on. In this manuscript, PI hollow microspheres are fabricated by constructing a crosslinked structure combined with gradient heating. The formation of PI hollow microspheres includes gas nucleation, expansion, and imidization. The PI hollow microspheres size is controlled by adjusting polyester ammonium salts size, and microspheres size is distributed in 309–956 µm. PI hollow microspheres have lightweight, excellent heat resistance and carbonization performance, bulk density, initial decomposition temperature, and weight residue at 800 °C is 87.3–178.6 kg m −3 , 533.6 °C and 59.8%. The PI hollow microspheres have potential applications in high-temperature resistant and multifunctional composite materials preparation. Moreover, this method is simple, efficient, and highly operable, which can be used for large-scale production of PI hollow microspheres.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
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2021
·Vol. 222
·期 19
·2100197
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IF 2.527
Yinfu Luo,Long Ni,Cheng Zhang,Liwei Yan,Huawei Zou,Shengtai Zhou,Mei Liang
Lightweight and excellent thermal stability hollow polyimide (PI) microspheres play an important role in high-end engineering applications such as aerospace, marine use among others. Herein, a simple approach is proposed to scalable fabrication of hollow PI microspheres with controllable sizes by powder foaming method combined with gradient heating strategy. The diameter of PI microspheres ranges from 295.5 to 1479.6 µm with a wall thickness of ≈7.78 µm. Interestingly, the diameter of PI microspheres exhibits a good correlation with the size of polyester ammonium salt (PEAS) particles. The hollow PI microspheres demonstrate excellent heat resistance with a bulk density ranging from 56.9 to 132.2 kg m –3 . Furthermore, PI microspheres could be readily converted into carbon microspheres without destroying their original integrity, which shows potential applications in preparing multifunctional composites. The proposed method is easily scalable which can be adopted to fabricate hollow PI microspheres at large quantities for industrial applications.
研究领域:
材料科学
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航空航天工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
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IF 8.742
Jinxue Cheng,Naijia Zhao,Yuxin Zhang,Yan Huang,Qinglin Huang,Changfa Xiao
Uniform-sized core-shell microspheres have received more and more attentions owing to the therapeutic application such as controlled release and drug targeting. In this work, we proposed a facile method to fabricate core-shell microspheres with uniform size. Polymethyl methacrylate (PMMA)@polylactic acid (PLA) core-shell microspheres with controllable core and shell size were prepared by combining membrane emulsification (ME) technology and solvent evaporation method. Specially, the near-field electrospinning (NFES) poly(tetrafluoroethylene) (PTFE) membranes and biaxially stretched PTFE membranes were utilized in the ME process. Subsequently, a series of PMMA@PLA core-shell microspheres were successfully prepared, where the core size of microspheres depended on the hydrophobic NFES PTFE membrane while the shell size depended on the hydrophilic biaxially stretched PTFE membrane. Meanwhile, the variation of droplet size and distribution with the evaporation temperature, pressure and continuous phase rotating speed were also investigated. When the solvent evaporation temperature was 40 °C, the obtained PMMA@PLA core-shell microspheres showed optimal morphology and size distribution. Moreover, the shell size increased with the increase of operating pressure and the decrease of continuous phase rotating speed. This facile strategy showed great potential for efficiently preparing uniform-sized core-shell microspheres in large scale.
研究领域:
材料科学
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制药工程
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生物医学工程
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DOI
高影响因子
MATERIALS LETTERS
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2019
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IF 3.019
Li Guo,Lulu Shen,Song Chen,Aili Wei,Di Huang,Akiyoshi Osaka,Weiyi Chen
Silica nanotubes with controllable size were synthesized as the electrospun silk fibroin/gelatin composite nanofibers as novel sacrificial template were firstly coated with silica in the Stöber-type sol-gel precursor and then burned out at 600 °C. The aqueous stability of composite nanofibers was much better than that of gelatin nanofibers due to the presence of silk fibroin. FT-IR spectrum showed that silica nanotubes had the strong adsorption band at 1115 cm −1 for Si–O–Si groups. TEM observation showed that the diameter of silica nanotubes could be controlled from 225 ± 11 nm to 470 ± 9 nm by tuning the silk fibroin/gelatin weight ratio from 1.25 to 2. After incubation with the osteoblast MG63 cells, silica nanotubes (0–200 μg/mL) had no significant cytotoxicity and presented excellent biocompatibility.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Guohua Wang,Yicheng Wang,Guoqiang Lu,Shiyu Dong,Ruifen Tang,Yingying Zhao,Jun Nie,Xiaoqun Zhu
Hydrogel tubes made of sodium alginate (SA) have potential applications in drug delivery, soft robots, biomimetic blood vessels, tissue stents, and other fields. However, the continuous preparation of hollow SA hydrogel tubes with good stability and size control remains a huge challenge for chemists, material scientists, and medical practitioners. Inspired by the plant apical growth strategy, a new method named soft cap-guided growth was proposed to produce SA hydrogel tubes. Due to the introduction of inert low gravity substances, such as air and heptane, into the extrusion needle in front of calcium chloride solution to form a soft cap, the SA hydrogel tubes with controllable sizes were fabricated rapidly and continuously without using a template through a negative gravitropism mechanism. The SA hydrogel tubes had good tensile strength, high burst pressure, and good cell compatibility. In addition, hydrogel tubes with complex patterns were conveniently created by controlling the motion path of a soft cap, such as a rotating SA bath or magnetic force. Our research provided a simple innovative technique to steer the growth of hydrogel tubes, which made it possible to mass produce hydrogel tubes with controllable sizes and programmable patterns.
研究领域:
材料科学
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化学
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生物医学工程
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组织工程
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产品关联
DOI
PubMed
高影响因子
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