Surface Composition of Poly(methylphenylsiloxane)-Polystyrene Block Copolymers
Surface Composition of Poly(methylphenylsiloxane)-Polystyrene Block Copolymers
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聚(甲基苯基硅氧烷)-聚苯乙烯嵌段共聚物的表面组成
DOI：
10.1021/ma00107a002
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Arman R Ashraf
中科院分区：
文献类型：
--
作者：
S. J. Clarson;J. O. Stuart;C. E. Selby;A. Sabata;Steven D Smith;Arman R Ashraf
用飞行时间二次离子质谱仪(TOFSIMS)分析了聚甲基苯基硅氧烷(PMPS)均聚物和聚甲基苯基硅氧烷-聚苯乙烯(PMPS-PS)两嵌段共聚物的表面组成。这种方法探测样品的深度为几埃，表面灵敏度高，表明嵌段共聚物样品的表面既有聚甲基苯基硅氧烷，也有聚苯乙烯链段。这些结果可能与聚二甲基硅氧烷(PDMS)嵌段和共混物的行为形成对比，在PDMS嵌段和共混物中，-[O-Si(CH3)2]-重复单元的低表面能通常导致表面分离和PDMS表面完全覆盖。用差示扫描量热法研究了嵌段共聚物的热性能，发现其玻璃化转变温度为单一玻璃化转变温度，表明其为单一相形态。嵌段共聚物的表面也表现出-Si(CH3)3基团的浓缩，这些基团是PMPS的末端基团，可能是由于三甲基硅基的低表面能
The surface compositions of poly(methylphenylsiloxane) (PMPS) homopolymers and poly(methylphenylsiloxane)-polystyrene (PMPS-PS) diblock copolymers have been analyzed using time-of-flight secondary ion mass spectrometry (TOFSIMS). The high surface sensitivity of this method, which probes samples to depths of a few Angstroms, showed the block copolymer samples to have both poly(methylphenylsiloxane) and polystyrene segments present at the surface. These results may be contrasted with the behavior seen for poly(dimethylsiloxane) (PDMS) blocks and blends, where the low surface energy of the -[O-Si(CH 3 ) 2 ]- repeat units typically leads to surface segregation and complete PDMS surface coverage is seen. Investigation of the thermal characteristics of the block copolymers by differential scanning calorimetry revealed a single glass transition temperature, indicating a single phase morphology. The surfaces of the block copolymers also showed an enrichment of -Si(CH 3 ) 3 groups, which are the terminal groups of the PMPS, presumably due to the low surface energy of the trimethylsilyl groups