Selecting for Surface-Induced vs Bulk Crystallization in P3HT Thin Films: Distinct Morphology, Orientation, and Linear Growth Rates

被引：4

作者：

Kuebler, Jesse ^{[1
,2
]}

Dhapola, Sunil ^{[1
,2
]}

Fernandez-Ballester, Lucia ^{[1
,2
]}

机构：

[1] Univ Nebraska Lincoln, Dept Mech & Mat Engn, Lincoln, NE 68588 USA

[2] Univ Nebraska Lincoln, Nebraska Ctr Mat & Nanosci, Lincoln, NE 68588 USA

来源：

MACROMOLECULES | 2024年 / 57卷 / 06期

基金：

美国国家科学基金会;

关键词：

CHARGE-TRANSPORT; ULTRATHIN FILMS; REGIOREGULAR POLY(3-HEXYLTHIOPHENE); POLY(ETHYLENE OXIDES); OXIDIZED SILICON; MOLECULAR-WEIGHT; CHAIN MOLECULES; THICKNESS; CRYSTALS; MOBILITY;

D O I：

10.1021/acs.macromol.3c02164

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

By removal of the air-polymer interface in poly(3-hexylthiopene) (P3HT) thin films, bulk crystallization morphology is attained, where highly absorbing "bulk objects" grow throughout the film thickness at T similar to T (C,BULK) and exhibit no preferential crystalline orientation. In contrast, films with a free surface develop highly edge-on oriented 2D spherulites ("circulites") at the air-polymer interface at T >> T (C,BULK), which then promote edge-on oriented, featureless crystallization in the underlayer near T C,BULK. Interestingly, circulites exhibit similar to 10x faster linear growth rates than bulk objects-despite both morphologies consisting of the same crystal form-at temperatures where chain mobility is not expected to dominate growth rates, suggesting that another mechanism may be at play. Overall, these results provide insight into the role of the free surface in the crystallization process and indicate that the presence or absence of an air-polymer interface can be used to control the semicrystalline morphology and orientation of P3HT thin films.

引用

页码：2639 / 2650

页数：12

共 84 条

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