Determination of Interfacial Mixing in Tapered Block Polymer Thin Films: Experimental and Theoretical Investigations
Determination of Interfacial Mixing in Tapered Block Polymer Thin Films: Experimental and Theoretical Investigations
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锥形嵌段聚合物薄膜中界面混合的测定：实验和理论研究
DOI：
10.1021/acs.macromol.6b00946
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发表时间：
2016
期刊：
影响因子：
5.5
通讯作者：
Thomas H. Epps
中科院分区：
文献类型：
--
作者：
M. Luo;Jonathan R. Brown;Roddel A. Remy;D. Scott;M. Mackay;L. Hall;Thomas H. Epps
锥形嵌段聚合物是一类新兴的大分子，具有独特和多样的自组装行为和性能。在这里，我们直接检查的操作自组装界面的聚（异戊二烯-b-苯乙烯）（I-S）为基础的嵌段聚合物（BP）通过合成非锥形（I-S），正常锥形（I-IS-S），和反锥形（I-SI-S）BP与控制的单体链段分布。我们提供了第一个直接测量这些锥形聚合物通过X射线反射率（XRR）的界面混合。从XRR的密度分布进行比较，从流体密度泛函理论（fDFT）的结果具有良好的一致性。我们发现，我们的正常锥形BP（30体积%锥形）有类似的界面混合二嵌段聚合物，而我们的倒锥形BP（30体积%锥形）有更宽的接口。此外，差示扫描量热法（DSC）研究阐明了锥形化对每个BP相的玻璃化转变温度（Tg）和热容变化（ΔCP）的影响。
Tapered block polymers are an emerging class of macromolecules with unique and diverse self-assembly behavior and properties. Herein, we directly examine the manipulation of self-assembled interfaces in poly(isoprene-b-styrene) (I-S)-based block polymers (BPs) by synthesizing non-tapered (I-S), normal tapered (I-IS-S), and inverse tapered (I-SI-S) BPs with controlled monomer segment distributions. We provide the first direct measurements of interfacial mixing for these tapered polymers through X-ray reflectivity (XRR). The density profiles from XRR are compared to results from fluids density functional theory (fDFT) with good agreement. We find that our normal tapered BPs (30 vol % tapering) have similar interfacial mixing to diblock polymers, while our inverse tapered BPs (30 vol % tapering) have much wider interfaces. Additionally, differential scanning calorimetry (DSC) studies elucidate the influence of tapering on the glass transition temperature (Tg) and change of heat capacity (ΔCP) for each BP pha...