Hierarchical Structure in Nanoscale Thin Films of a Poly(styrene-b-methacrylate grafted with POSS) (PS214-b-PMAPOSS27)

被引：53

作者：

Ahn, Byungcheol ^{[2
,3
]}

Hirai, Tomoyasu ^{[1
]}

Jin, Sangwoo ^{[2
,3
]}

Rho, Yecheol ^{[2
,3
]}

Kim, Kwang-Woo ^{[2
,3
]}

Kakimoto, Masa-aki ^{[1
]}

Gopalan, Padma ^{[4
]}

Hayakawa, Teruaki ^{[1
]}

Ree, Moonhor ^{[2
,3
]}

机构：

[1] Tokyo Inst Technol, Dept Organ & Polymer Mat, Meguro Ku, Tokyo 1528552, Japan

[2] Pohang Univ Sci & Technol, Pohang Accelerator Lab, Div Adv Mat Sci,BK Sch Mol Sci, Ctr Electrophoto Behav Adv Mol Syst,Dept Chem, Pohang 790784, South Korea

[3] Pohang Univ Sci & Technol, Polymer Res Inst, Pohang 790784, South Korea

[4] Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI USA

来源：

MACROMOLECULES | 2010年 / 43卷 / 24期

基金：

美国国家科学基金会; 新加坡国家研究基金会;

关键词：

X-RAY-SCATTERING; POLYHEDRAL OLIGOMERIC SILSESQUIOXANE; HEXAGONALLY PERFORATED LAYER; DIBLOCK COPOLYMER FILMS; ORGANOSILICATE DIELECTRIC FILMS; POLYSTYRENE-B-POLYISOPRENE; BLOCK-COPOLYMER; QUANTITATIVE-ANALYSIS; TRIBLOCK COPOLYMERS; ELECTRON-MICROSCOPY;

D O I：

10.1021/ma101276d

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

An interesting organic-inorganic diblock copolymer poly(styrene-b-methacrylate grafted with polyhedral oligomeric silsesquioxane) (PS b PMAPOSS), with PS (an average degree of polymerization (DP) over bar of 214) and PMAPOSS ((DP) over bar = 27) blocks was prepared PS214 b PMAPOSS(27) The morphological structures in nanoscale thin films of PS214 b-PMAPOSS(27) and their temperature dependent changes were investigated in detail by performing grazing incidence X ray scattering (GIXS) with a synchrotron radiation source GIXS formulas based on structural models were derived for the quantitative analysis of the two dimensional (2D) scattering data In addition the thermal properties of the diblock copolymer were characterized it was found to be stable up to 330 degrees C, and to undergo a glass transition at 96 degrees C (PS block) and a melting transition at 173 degrees C (PMAPOSS block) The quantitative 2D GIXS analysis found that the diblock copolymer molecules in the thin films undergo phase separation into PS and PMAPOSS domains, which generates a lamellar structure Surprisingly, in the solvent-annealed films with and without subsequent thermal annealing the lamellar structure is completely oriented in the out of plane of the film and is stable up to the degradation temperature The PMAPOSS layers in the lamellar structure were found to consist of two sublayers, namely a densely ordered layer composed of vertically oriented orthorhombic crystals and a less ordered layer that consists of molecularly stacked layers that are oriented vertically In both the sublayers, the PMAPOSS block chains have helical conformations and thus are present as molecular cylinders These molecular cylinders are always oriented in the film plane On heating the orthorhombic crystals and the molecularly stacked layers melt over the range 170-190 degrees C On subsequent cooling, the orthorhombic crystals and molecularly stacked layers are not fully recovered, which indicates that the formation of orthorhombic crystals and stacked layers in the PMAPOSS domains requires thermal annealing

引用

页码：10568 / 10581

页数：14

共 89 条

[1] Macroscopic orientation of block copolymer cylinders in single-layer films by shearing [J].