Frequency Response of Polymer Films Made from a Precursor Colloidal Monolayer on a Nanomechanical Cantilever
Frequency Response of Polymer Films Made from a Precursor Colloidal Monolayer on a Nanomechanical Cantilever
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纳米机械悬臂梁上由前体胶体单层制成的聚合物薄膜的频率响应
作者：
Retsch;Gutmann;Koynov;Berger
采用纳米机械力测试仪（NMC）对聚苯乙烯（PS）胶体单分子膜的成膜过程和力学性能进行了表征。在空气-水界面处制备了直径为400 - 800 nm的紧密堆积的六方单层胶体，然后以受控的方式转移到NMC表面上。通过测量NMC的共振频率（~ 12 kHz）研究了单层退火后的膜形成过程。在加热非交联PS胶体时，我们可以确定两个转变温度。第一个转变是由于聚合物胶体合并成膜。在147 ± 3 °C下测量的该转变温度在随后的加热循环中保持恒定。我们将此转变温度归因于PS的玻璃化转变温度Tg，并通过动态力学热分析（DMTA）和时间温度叠加原理证实了这一点。第二转变温度（175 ± 3 °C）与膜形成过程的结束相关联，并且仅针对第一加热循环测量。此外，胶体单分子层转变成均匀的膜保留了NMC上的质量负载，这使得可以优雅地测定PS的杨氏模量（1.3GPa）。
Nanomechanical cantilevers (NMC) were used for the characterization of the film formation process and the mechanical properties of colloidal monolayers made from polystyrene (PS). Closely packed hexagonal monolayers of colloids with diameters ranging from 400 to 800 nm were prepared at the air–water interface and then transferred in a controlled way on the surface of NMC. The film formation process upon annealing of the monolayer was investigated by measuring the resonance frequency of the NMC (≈12 kHz). Upon heating of non-cross-linked PS colloids, we could identify two transition temperatures. The first transition resulted from the merging of polymer colloids into a film. This transition temperature at 147 ± 3 °C as measured at ≈12 kHz remained constant for subsequent heating cycles. We attributed this transition temperature to the glass transition temperatureTgof PS which was confirmed by dynamic mechanical thermal analysis (DMTA) and using the time temperature superposition principle. The second transition temperature (175 ± 3 °C) was associated with the end of the film formation process and was measured only for the first heating cycle. Furthermore, the transition of the colloidal monolayer into a homogeneous film preserved the mass loading on the NMC which allowed determination of the Young’s modulus of PS (≈3 GPa) elegantly.
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影响因子：
5.5
作者：
Jung, Namchul;Jeon, Sangmin
通讯作者：
Jeon, Sangmin
影响因子：
5.5
作者：
Jung, Namchul;Seo, Hyejung;Jeon, Sangmin
通讯作者：
Jeon, Sangmin
影响因子：
2.5
作者：
C. R. Bradley;N. Jalili;S. Nett;Li-Qiang Chu;R. Förch;J. Gutmann;R. Berger
通讯作者：
C. R. Bradley;N. Jalili;S. Nett;Li-Qiang Chu;R. Förch;J. Gutmann;R. Berger
对于不同的溶剂组合物，由低 Tg 颗粒形成蒸汽诱导成膜。
影响因子：
9.9
作者：
E. Arda;S. Kara;A. Saraç;O. Pekcan
通讯作者：
O. Pekcan
影响因子：
5.5
作者：
Lenz, Sebastian;Nett, Sebastian K.;Gutmann, Jochen S.
通讯作者：
Gutmann, Jochen S.