초록 |
Organic nanoparticles (ONPs) in the form of star polymers and single chain nanoparticles (SCNPs) are used as additives in block copolymer (BCP)/ONP nanocomposite thin films to induce vertical microdomains on bare SiOx substrate. Neutral ONPs for both blocks of BCP neutralize the substrate and the free surface via an entropy-driven boundary surface segregation process, which differs from conventional neutralization process relying on surface chemistry. To examine the architectural effect of ONPs for surface segregation, neutral star polymers with ∼30, 21, and 6 arms and single-chain nanoparticles are used as fillers in PS-b-PMMA thin films in an attempt to produce perpendicular microdomains. Consequently, it was observed that ∼30- and 21-arm star polymers and SCNPs, which behave like hard particles having excluded volume interactions with host BCPs, effectively induce vertical microdomains, while soft particle-like 6-arm stars lead to morphological compatibilization with BCPs. |