丁彬老师的纳米蛛网结构

Ding B, Li C, Miyauchi Y, et al. Formation of novel 2D polymer nanowebs via electrospinning [J]. Nanotechnology, 2006, 17(15): 3685.

摘要的思路层次

  • We have found a procedure for generating novel two-dimensional (2D)
    nanowebs in three-dimensional (3D) fibrous mats by optimization of various
    processing parameters during electrospinning.
    我们做了什么
  • The electrospun fibres act as a support for the ‘fishnet-like’ nanowebs comprising interlinked one-dimensional (1D) nanowires.
    什么样的结构
  • The average diameter of the nanowires contained in typical nanowebs is about one order of magnitude less than that of conventional electrospun fibres.
    结构的详细信息
  • due to theelectrically forced fast phase separation of the charged droplets which moveat high speed between the capillary tip and the collector.
    结构形成机理
  • strongly affected by the applied voltage, ambient relative humidity, kinds ofsolvents, solution concentration and distance between the capillary tip andthe collector.
    结构形成条件

介绍部分

  • 简介下优点以及历史
  • 溶剂挥发不完全形成的缺陷薄膜可调控
  • 高比表面积可用在探测,过滤和组织工程。越细越好,前人:低溶度和加盐
  • 我们做到了低于50 nm

PAA实验部分

  • 解释缺陷产生原因
    PAA的SEM水中和乙醇中,浓度:6 wt%, 电压:30 kV, 距离 15 cm 相对湿度 20%
    缺陷部分变成网
    The formation of these webs from films was considered to bedue to the fast phase separation of polymer and solvent in thecharged droplet.
  • 湿度的影响很重要
    直接影响挥发速度,影响挥发,增大直径。
  • 电压
    20kv看不到web结构。30kv可以看到细细的spider。
    6% 浓度看不到啥网,8%下看到一点。10%下多多滴。
    ** Therefore, the shape, diameter and uniformity of holes in PAA nanowebs could be adjusted by changing the solution concentrations. **

PA 6部份

  • 电压影响
    形成蛛网的关键在电压哦
    浓度 15%,距离15 cm,相对湿度 20%,电压为10(小区域网),20,30kv(最多网)。 而且对湿度不敏感哦。因为抗化学性好,只能溶解在少数溶剂中。水不溶PA 6。
  • 距离影响

nanowebs are strongly affected byspinning distance.

5cm 处伸展不开。25 cm充分展开。

  • 典型例子
    20 % 浓度,25kv,15 cm 20%湿度

结论

  • In summary, we have demonstrated the fabrication of PAA
    and nylon-6 nanowebs which are stacked layer-by-layer and
    widely distributed in the 3D structure of fibrous mats.
    一句话总结我们做了啥
  • The development of PAA nanowebs indicated the process of
    formation of nanowebs.
    复述实验第一部份
  • The splitting of defect films into nanowebs occurred only under certain conditions, such as high applied voltage, low relative humidity and fast phase separation between polymers and solvents.
    形成关键:四个条件
  • Meanwhile, the morphologyand area density of nanowebs were an overall result of variouselectrospinning operational parameters like relative humidity,applied voltage, kinds of solvents, spinning distance andsolution concentration.
    四个条件叠加结果
  • one-tenth that of common electrospun fibres.
    效果:达到1/10
  • Up until now, the formation of defect films was the usual phenomenon during electrospinning. However, now possibilities have expanded with our research, and other materials with electrospinnability also have the possibility of forming nanowebs.
    我们化腐朽为神奇:升华主题。。。

推荐阅读更多精彩内容