Article
Polymer Science
Ali Masud, Melanie Longanecker, Sonal Bhadauriya, Maninderjeet Singh, Wenjie Wu, Kshitij Sharma, Tanguy Terlier, Abdullah M. Al-Enizi, Sushil Satija, Jack F. Douglas, Alamgir Karim
Summary: The use of an ionic liquid (IL) with high cohesion and low volatility can enhance the ordering and alignment in block copolymer (BCP) films while maintaining high molecular mobility. This approach has potential applications in preparing defect-free multilayer films.
Article
Chemistry, Physical
Ting Qu, Xue Hu, Zejiang Zhou, Yihe Liu, Jie Wang, Fuqiang Hu, Fei Zhong, Jing Ni, Fan Cheng, Chunli Gong, Hai Liu
Summary: An effective approach to construct perpendicularly oriented lamellar domains in block copolymer films has been reported. The method involves incorporating azobenzene groups into the side chains of the block copolymer and manipulating the flexible spacers. Different morphologies of vertical lamellae can be obtained on various substrates. The study provides a new avenue for engineering the morphology of perpendicularly aligned lamellar films.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Hoang M. Nguyen, Ariane V. Mader, Swarnalok De, Jaana Vapaavuori
Summary: The effect of dip-coating parameters on the morphology evolution of BCP thin films was studied, obtaining a hexagonally packed BCP pattern with long-range order without the need for post-annealing processes. This study extends the understanding of the parameters affecting the formed surface patterns and their interplay to more materials.
NANOSCALE ADVANCES
(2021)
Article
Polymer Science
Alexey S. Merekalov, Yaroslav I. Derikov, Alexander A. Ezhov, Yury A. Kriksin, Igor Ya. Erukhimovich, Yaroslav Kudryavtsev
Summary: The rearrangement of lamellar and hexagonal patterns in thin films of copolymers is studied under the influence of an AC electric field and chloroform vapor. It is shown that a strong AC field can effectively orient microphase-separated domains along the field direction. The risk of breakdown is reduced and effects related to ionic transport are eliminated. The role of exposure time, field strength, and frequency is investigated. The observed morphological rearrangements can be important for practical applications.
Article
Polymer Science
Jun Yuan, Xiang Liu, Yingying Wang, Guangjian Zeng, Gang Li, Xue-Hui Dong, Tao Wen
Summary: This study investigates the self-assembly behavior of chiral block copolymers under one-dimensional spatial confinement, revealing the formation of chiral nanostructures and the influence of shape and topology on self-assembly.
Article
Chemistry, Physical
Jia-Wen Hong, Jung-Hong Chang, Iris Ching-Ya Chang, Ya-Sen Sun
Summary: By studying the phase behavior of substrate-supported films, we found that different nano-domains appear sequentially with increasing PS content, including lamellae, perforated layers, double gyroid, and cylinders. Annealing temperature and film thickness have significant effects on the formation of perforated layers and double gyroids, with lower annealing temperatures favoring a greater fraction of perforated layers in thick films.
Article
Polymer Science
Wennie Yun Lee, Dana Chapman, Fei Yu, William R. T. Tait, R. Paxton Thedford, Guillaume Freychet, Mikhail Zhernenkov, Lara A. Estroff, Ulrich B. Wiesner
Summary: Self-assembled block copolymer thin films and their nanocomposites have diverse applications due to their nanostructures. Optical super-resolution microscopy (OSRM) has emerged as an alternative method for characterizing nanoscopic polymer morphology. This study focuses on self-assembled triblock terpolymer thin films with all three blocks exposed at the top surface, and demonstrates the use of OSRM for multicolor characterization of chemically distinct nanodomains.
Review
Chemistry, Physical
Przemyslaw Pula, Arkadiusz Leniart, Pawel W. Majewski
Summary: Solvent-assisted block copolymer self-assembly is a promising method for controlling the morphology and ordering kinetics of BCPs, thus advancing their practical applications. However, the development of a universal BCP patterning protocol remains challenging due to various factors influencing the self-assembly scenario. This review aims to summarize the seminal reports and latest progress in solvent-assisted directed self-assembly of BCPs, providing theoretical background and highlighting significant research areas and emerging high-tech applications where solvent-assisted processing could have a dominant role.
Article
Chemistry, Multidisciplinary
Kevin Ho, Kris S. Kim, Sissi de Beer, Gilbert C. Walker
Summary: Investigations on the transitional composition between two thin-film morphologies of the block copolymer, polystyrene-block-poly(tert-butyl acrylate) (PS-b-PtBuA), were conducted using near-field infrared spectroscopy and atomic force microscopy mechanical measurements. The techniques allowed for block identification with nanoscale spatial resolution and elucidated the material's sub-surface composition, revealing distinct patterns of PS and PtBuA formation in different regions of the polymer film.
Article
Polymer Science
Mingyang Chen, Yuguo Chen, Yanyan Zhu, Ying Jiang, David Andelman, Xingkun Man
Summary: We investigated the influence of chain flexibility on the self-assembly behavior of symmetric diblock copolymers (BCPs) in thin film confinement. Using worm-like chain (WLC) self-consistent field theory, we studied the stability of parallel and perpendicular orientations of BCP lamellar phases under varying chain flexibilities. The results showed that the stability of perpendicular lamellae increases with chain rigidity, except for the case of rigid chains on rough substrates where the stability decreases. We also demonstrated the effect of substrate roughness on the critical value of substrate preference for the transition from perpendicular-to-parallel lamellar phases.
Review
Polymer Science
Polyxeni P. Angelopoulou, Ioannis Moutsios, Gkreti-Maria Manesi, Dimitri A. Ivanov, Georgios Sakellariou, Apostolos Avgeropoulos
Summary: This review article discusses the origins of self-assembly behavior of linear and non-linear block co-and terpolymers and their application towards the fabrication of high-resolution patterns for nanolithography applications. Comparative analysis for the microphase separation in bulk and thin films is provided, to map the fundamentals of various types of block copolymers (BCPs) inherent properties prior to their use in advanced applications. The opportunities of high-chi/low-N and/or complex architecture co-and terpolymers to self-assemble into nanostructures that are beyond the limitations of current lithographic techniques will be presented. The role of molecular characteristics and immiscibility of the blocks on the formation of sub-10 nm or sub-5 nm structures will be discussed. Recent advances in directed self-assembly (or DSA) enable low defect density, extremely minimal dimensions, facile processability, etching selectivity, low-cost and ability to design various patterns. The opportunities of these strategies will be discussed in the context of technological standard requirements and their potential will be evaluated.
PROGRESS IN POLYMER SCIENCE
(2022)
Article
Chemistry, Physical
Chongyong Nam, Won Bo Lee, YongJoo Kim
Summary: This study used dissipative particle dynamics (DPD) to investigate the assembled structures of rod-coil diblock copolymer and nanoparticle blends. The distribution of nanoparticles in the smectic lamellar phase was analyzed, and the interactions between nanoparticles and rods or coils were discussed.
Article
Polymer Science
Hirofumi Harada, Takeshi Saito, Masatoshi Tokita
Summary: The thermal conductivity of polymers can be effectively enhanced by liquid crystallinity, which exhibits anisotropic thermal conductivity with a greater magnitude in the orientation direction. This study investigated the correlation between liquid crystal structures and thermal diffusivity, and found that smectic layers can enhance thermal diffusivity in their normal direction.
Article
Chemistry, Multidisciplinary
Erna Febriyanti, Nadiatus Silmi, Veinardi Suendo, Rino R. Mukti, Pipit U. Vivitasari, Damar R. Adhika, Yutaka Majima, Suprijadi, Ismunandar
Summary: The formation mechanism and morphological evolution of bicontinuous concentric lamellar silica particles were thoroughly investigated in this study. The results revealed that the formation of bcl silica involves hydrolysis, condensation reactions, and phase segregation within reverse micelles. The study also focused on the thermodynamics of the phase segregation process and observed a change in lamellar orientation as the lamellae thickness varied. The findings provide insights into the synthesis of silica particles with unique morphologies.
Article
Chemistry, Analytical
Bianca M. de Lima, Patrick L. Hayes, Paula M. Wood-Adams
Summary: In this study, SFG spectroscopy was used to analyze the lamellar orientation at the surface of semi-crystalline polystyrene thin films, revealing a perpendicular orientation of the chains to the substrate. The study also explored the challenges associated with SFG measurements of heterogeneous surfaces and proposed the correlation between SFG intensity ratios and the progress of crystallization and surface crystallinity. This research demonstrates the potential application of SFG spectroscopy in the conformational analysis of polymeric crystalline structures at interfaces and opens up possibilities for investigating more complex polymeric structures and crystalline arrangements.
ANALYTICA CHIMICA ACTA
(2023)
