Raegen A N, Massa M V, Forrest J A, Dalnoki-Veress K
Department of Physics & Astronomy and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, ON, Canada.
Eur Phys J E Soft Matter. 2008 Dec;27(4):375-7. doi: 10.1140/epje/i2008-10394-3. Epub 2008 Nov 20.
We have used nulling ellipsometry to measure the glass transition temperature, T (g) , of thin films of polystyrene in ambient, dry nitrogen, and vacuum environments. For all environments, the measured T (g) values decrease with decreasing film thickness in a way that is quantitatively similar to previously reported studies in ambient conditions. These results provide strong reinforcement of previous conclusions that such reduced T (g) values are an intrinsic property of the confined material. Furthermore, the results are in contrast to recent reports which suggest that the T (g) reductions measured by many researchers are the results of artifacts (i.e. degradation of the polymer due to annealing in ambient conditions, or moisture content).
我们使用消光椭偏仪在环境、干燥氮气和真空环境中测量了聚苯乙烯薄膜的玻璃化转变温度T(g)。对于所有环境，测得的T(g)值都随着薄膜厚度的减小而降低，其方式在定量上与先前在环境条件下报道的研究相似。这些结果有力地支持了先前的结论，即这种降低的T(g)值是受限材料的固有特性。此外，这些结果与最近的报道相反，那些报道表明许多研究人员测得的T(g)降低是人为因素的结果（即聚合物在环境条件下退火或水分含量导致的降解）。
