School of Materials Science and Engineering, Tianjin University, Tianjin 300072, P. R. China.
Soft Matter. 2017 May 3;13(17):3091-3098. doi: 10.1039/c7sm00379j.
The dewetting behavior of ring polystyrene (RPS) film and linear polystyrene (LPS) film on silanized Si substrates with different grafting densities and PDMS substrate was investigated. Results showed that polymer architectures greatly influenced the dewetting behavior of the thin polymer film. On the silanized Si substrate with 69% grafting density, RPS chains exhibited stronger adsorption compared with LPS chains, and as a result the wetting layer formed more easily. For LPS films, with a decreased annealing temperature, the stability of the polymer film changed from non-slip dewetting via apparent slip dewetting to apparently stable. However, for RPS films, the polymer film stability switched from apparent slip dewetting to apparently stable. On the silanized Si substrate with 94% grafting density, the chain adsorption became weaker and the dewetting processes were faster than that on the substrate with 69% grafting density at the same experimental temperature for both the LPS and RPS films. Moreover, on the PDMS substrate, LPS films always showed non-slip dewetting, while the dewetting kinetics of RPS films switched from non-slip dewetting to slip dewetting behaviour. Forming the wetting layer strongly influenced the stability and dewetting behavior of the thin polymer films.
研究了具有不同接枝密度的硅烷化硅衬底和 PDMS 衬底上的环聚苯乙烯（RPS）膜和线性聚苯乙烯（LPS）膜的去湿行为。结果表明，聚合物结构极大地影响了薄膜聚合物的去湿行为。在接枝密度为 69%的硅烷化硅衬底上，RPS 链比 LPS 链表现出更强的吸附作用，因此更容易形成润湿层。对于 LPS 薄膜，随着退火温度的降低，聚合物薄膜的稳定性从非滑移去湿转变为明显的滑移去湿，再到明显稳定。然而，对于 RPS 薄膜，聚合物薄膜的稳定性从明显的滑移去湿转变为明显稳定。在接枝密度为 94%的硅烷化硅衬底上，对于 LPS 和 RPS 薄膜，在相同的实验温度下，与接枝密度为 69%的衬底相比，链吸附作用减弱，去湿过程更快。此外，在 PDMS 衬底上，LPS 薄膜始终表现出非滑移去湿，而 RPS 薄膜的去湿动力学则从非滑移去湿转变为滑移去湿行为。形成润湿层强烈影响薄膜聚合物的稳定性和去湿行为。
