Mechanism and Kinetics of Fullerene Association in Polystyrene Thin Film Mixtures
Mechanism and Kinetics of Fullerene Association in Polystyrene Thin Film Mixtures
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DOI：
10.1021/ma2004458
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发表时间：
2011-05
期刊：
影响因子：
5.5
通讯作者：
Him Cheng Wong;J. Cabral
中科院分区：
文献类型：
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作者：
Him Cheng Wong;J. Cabral
我们研究了等温退火模型均聚物薄膜中富勒烯 C60 缔合的机理和动力学。在混溶性阈值两侧加载 0–5% C60 质量分数的均匀聚苯乙烯 (PS) 薄膜，并随时间进行退火和监测。随着 C60 负载量和时间的增加，观察到从异质、稀疏、成核到渗流旋节线形态的转变。富勒烯缔合之后是结晶，这通过二维 Avrami 动力学进行量化。该过程的关键状态被确定为成核、渗滤、饱和和粗化阶段，并根据簇平均尺寸⟨r⟩、数密度Nd、面积分数Af和主波数q*的演变来定义。 “旋节线聚类”过程产生渗透横向形态和起伏的表面形貌，其波长 λ 和振幅 δh 可以通过温度 T、时间 t、膜厚度 h 和聚合物分子质量 Mw 进行调节。这些结果提供了...
We study the mechanism and kinetics of fullerene C60 association in model homopolymer thin films upon isothermal annealing. Uniform polystyrene (PS) films loaded with 0–5% C60 mass fraction, on both sides of the miscibility threshold, are annealed and monitored over time. A transition from heterogeneous, sparse, nucleation to a percolated spinodal morphology is observed with increasing C60 loading and time. Fullerene association is followed by crystallization, which is quantified by Avrami kinetics in two dimensions. Key regimes of the process are identified as nucleation, percolation, saturation and coarsening stages, and defined in terms of the evolution of cluster average size ⟨r⟩, number density Nd, area fraction Af, and dominant wavenumber q*. The “spinodal clustering” process results in a percolated lateral morphology and undulating surface topography whose wavelength λ and amplitude δh can be tuned with temperature T, time t, film thickness h and polymer molecular mass Mw. These results provide ins...