Article
Polymer Science
Sahori Imai, Masato Arakawa, Yohei Nakanishi, Mikihito Takenaka, Hiroyuki Aoki, Makoto Ouchi, Takaya Terashima
Summary: Microphase separation behavior of copolymers bearing quaternary ammonium cations and hydrophobic groups was studied. Sub-5 nm lamellar structures comprising cationic layers and hydrophobic layers were formed by annealing under humid conditions. The domain spacing could be controlled by tuning the length and composition of the hydrophobic groups. Transparent or translucent polymer materials containing small lamellar structures were obtained.
Article
Chemistry, Physical
Mengze Ma, Yao Fu
Summary: The electromechanical responses of lamellar neutral-charged diblock copolymers in thin films under an applied electric field were investigated using coarse-grained molecular dynamics simulations. The effects of the electric field on ion transport, morphological changes, and stress distribution were studied in detail, particularly focusing on ion dissociation and stress distribution under strong electric fields. The different stages of copolymer evolution under the electric field were characterized, paving the way towards establishing a modeling scheme for describing the response of ionic polymers in the presence of an applied electric field.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Polymer Science
Manjula Senanayake, Dipak Aryal, Gary S. Grest, Dvora Perahia
Summary: This study investigates the interfacial response of a symmetric block copolymer in different polar solvents using molecular dynamics simulations. The hydrophobic blocks initially dominate the interfacial response at the film boundary, while the distribution of solvents among different blocks determines the chemical composition and polymer conformation at the interface over time. These simulations offer direct molecular insight into the interfacial response of ionizable copolymers.
Article
Polymer Science
Ling-Ying Shi, Zhixiong Fei, Qian Wang, Lin Weng, Chenxiao Yin, Jinrui Sun, Zhihao Shen
Summary: Bottlebrush block copolymers (BBCPs) are intriguing architectural polymers that can produce various anisotropic nanostructures. This study presents a method for creating ordered silicon oxide patterns and particles on substrates using solvent vapor induced thin film self-assembly of BBCPs containing polydimethylsiloxane (PDMS) and polystyrene (PS) side chains. Different morphologies, including cylindrical or stripes-like, spherical, and ordered porous structures, as well as Janus particle-like structures, were achieved through solvent vapor annealing. The Janus particle-like structures were further transformed into meso-to-macroporous silicon oxide bowls after oxygen plasma etching. The study also discussed the effects of solvent vapor and backbone length on the self-assembly behavior of the thin film.
Article
Materials Science, Multidisciplinary
Daniel W. Weller, Guorong Ma, Luke A. Galuska, Song Zhang, Michael Stringer, Sophia Aracri, Weiyu Wang, Kunlun Hong, Xiaodan Gu
Summary: A new pore formation process was investigated for the manufacture of composite ultrafiltration membranes, utilizing the inherent ability of BCP to cavitate under strain for highly permeable and efficient membranes. The one-step membrane preparation process avoids tedious block removal steps. Different polymer types, molecular weights, and thicknesses influence the BCP's thin film morphology and ultimately filtration performance.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Polymer Science
Yi-Fang Chen, Jia-Wen Hong, Jung-Hong Chang, Belda Amelia Junisu, Ya-Sen Sun
Summary: The study focused on the influence of osmotic pressure on nanostructures in thin films, particularly the impact of UV-light exposure and acetic acid rinsing on lamellae orientation and surface wrinkling. It was found that the content of added PS chains affected the formation of lamellae and perforated layers in the films. The combination of UV-light exposure and acetic acid rinsing could produce different surface morphologies and mechanical properties in the films. The use of high-molecular-weight P(S-b-MMA) BCPs could help suppress surface wrinkling in the films.
Article
Materials Science, Multidisciplinary
Gang Zhang, Zhongyao Qin, Yu Qian, Jiaming Zhu
Summary: This study numerically investigates the temporal evolution of microstructure and kinetics of phase separation under electric fields for binary polymer blends. It reveals that the electric field has a significant influence on the morphological development and kinetic process of phase separation, with different rules observed at off-critical and critical compositions. The study also provides insights into the design of anisotropic microstructures by electric fields and their application in producing polymeric composite materials with superior properties.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Materials Science, Characterization & Testing
Wooseop Lee, Jiho Kim, Seungyun Jo, Boknam Chae, Hyungju Ahn, Du Yeol Ryu
Summary: This study presents a simple and effective method to probe the chemical distribution in self-assembled block copolymer films, and reveals the impact of solvent vapor annealing and thermal annealing on the chemical distribution, which is crucial for the formation of high-contrast chemical patterns.
Article
Nanoscience & Nanotechnology
Fei Yu, R. Paxton Thedford, Konrad R. Hedderick, Guillaume Freychet, Mikhail Zhernenkov, Lara A. Estroff, Katja C. Nowack, Sol M. Gruner, Ulrich B. Wiesner
Summary: Recent developments in quantum materials have shown promise in revolutionizing energy and information technologies. By utilizing block copolymers and niobia sol precursors, we successfully prepared mesoporous niobium carbonitride thin film superconductors through a scalable solution processing approach. This cost-effective and scalable method holds great potential for integration into existing microelectronics processing, combining the capabilities of soft matter self-assembly with quantum materials.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Polymer Science
Ryota Sujita, Sahori Imai, Makoto Ouchi, Hiroyuki Aoki, Takaya Terashima
Summary: By utilizing microphase separation, we have successfully achieved the creation of sub-4 nm lamellar structures in cationic polymers. These materials exhibit controllable domain spacing and can maintain stable lamellar structures at high temperatures.
Article
Polymer Science
Changyeon Lee, Chinedum O. Osuji
Summary: Liquid-crystal polymers combine the characteristics of liquid crystals and polymers, exhibiting intriguing physical phenomena and useful properties. Over the past nearly 50 years, there has been significant expansion in the field, with developments in new chain architectures, new classes of mesogens, and exploration of new properties and applications. Opportunities for LCPs, particularly in nanopatterning and beyond, are emerging with the ability to access small feature sizes and fluidity of the LC mesophase presenting compelling possibilities for orientation control.
Article
Polymer Science
Maninderjeet Singh, Wenjie Wu, Monali N. Basutkar, Joseph Strzalka, Abdullah M. Al-Enizi, Jack F. Douglas, Alamgir Karim
Summary: The study demonstrates a rapid self-assembly technique for achieving vertical orientation of block copolymer films on unmodified substrates, leading to faster formation of ordered structures.
Article
Polymer Science
R. Simonutti, D. Bertani, R. Marotta, S. Ferrario, D. Manzone, M. Mauri, M. Gregori, A. Orlando, M. Masserini
Summary: This study investigates the effect of using different common solvents on the self-assembly behavior of block copolymer nanoparticles, finding that the hydrogen bonding ability of the solvent strongly influences the size and shape of the particles, as well as their cytotoxicity.
Article
Chemistry, Physical
Maurice Brogly, Sophie Bistac, Diane Bindel
Summary: This study investigates the adsorption of PE-b-PEO block copolymer thin film on a gold substrate. The originality lies in using PM-IRRAS technology to study the conformational state of the copolymer thin film when physisorbed. The results indicate that the PEO sequences preferentially adsorb on the gold substrate, while the PE sequences are randomly distributed on the upper surface of the copolymer film.
APPLIED SURFACE SCIENCE
(2022)
Article
Polymer Science
Ki Hyun Kim, Mincheol Kim, Junsoo Moon, June Huh, Joona Bang
Summary: In this study, bottlebrush copolymers were designed as neutral additives to block copolymer (BCP) thin films, achieving vertically oriented microdomains through architectural effects. This concept could potentially be extended to various applications requiring polymer films with functional surfaces.
Article
Polymer Science
Gregory S. Doerk, Ruipeng Li, Masafumi Fukuto, Kevin G. Yager
Article
Chemistry, Multidisciplinary
Samantha R. Nowak, Katchen K. Lachmayr, Kevin G. Yager, Lawrence R. Sita
Summary: The ultra-low molecular weight disaccharide-polyolefin conjugates undergo irreversible thermotropic order-order transitions with temperature, forming nanostructured phases including the exceptional stable double gyroid phase. These results establish the class of sugar-polyolefin conjugates as a new material platform for nanoscience and nanotechnology.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Julia T. Early, Alison Block, Kevin G. Yager, Timothy P. Lodge
Summary: This study investigated the effect of molecular weight on the fragmentation kinetics of micelles formed by PB-PEO copolymers in an ionic liquid. It was found that the fragmentation times increased strongly with increasing degree of polymerization N, following a tau similar to N-1.8 relationship.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Multidisciplinary Sciences
Pawel W. Majewski, Aaron Michelson, Marco A. L. Cordeiro, Cheng Tian, Chunli Ma, Kim Kisslinger, Ye Tian, Wenyan Liu, Eric A. Stach, Kevin G. Yager, Oleg Gang
Summary: The rapid development of DNA-based assembly methods allows for the creation of organized nanomaterials with versatile capabilities. By creating inorganic, silica-based replicas of 3D periodic DNA-NP structures, the formed nanomaterials demonstrate excellent resiliency and stability under extreme conditions. This approach opens up new possibilities for the use of DNA assembly strategies in creating organized nanomaterials for a broad range of operational conditions.
Article
Polymer Science
Kristof Toth, Suwon Bae, Chinedum O. Osuji, Kevin G. Yager, Gregory S. Doerk
Summary: The study investigates the dependence of domain spacing in thin film blends of a lamellar polystyrene-block-poly(methyl methacrylate) diblock copolymer on thickness and homopolymer molar mass variations. The addition of homopolymers influences domain spacings, with thicker films and different homopolymer compositions leading to changes in lamellae orientation. Molecular simulations suggest that these effects are driven by homopolymer segregation to film surfaces.
Correction
Polymer Science
Kristof Toth, Suwon Bae, Chinedum O. Osuji, Kevin G. Yager, Gregory S. Doerk
Article
Chemistry, Multidisciplinary
Suwon Bae, Kevin G. Yager
Summary: Experimental and simulation studies have shown that the nanoscale morphology of BCP thin films is determined by chain architecture, and blending can stabilize new motifs and lead to the appearance of coexistence phases.
Editorial Material
Nanoscience & Nanotechnology
Kevin G. Yager
Summary: The self-assembly of a triblock bottlebrush polymer at one length scale determines the organization of the self-assembly at a smaller scale, creating a hierarchical unit cell.
NATURE NANOTECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Sebastian T. Russell, Suwon Bae, Ashwanth Subramanian, Nikhil Tiwale, Gregory Doerk, Chang-Yong Nam, Masafumi Fukuto, Kevin G. Yager
Summary: This article introduces a method to access new non-equilibrium morphologies using layering assembly. By controlling the initial configuration and ordering history of thin films, as well as thermal annealing for evolution, higher diversity of non-native morphologies can be achieved.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Gregory S. Doerk, Aaron Stein, Suwon Bae, Marcus M. Noack, Masafumi Fukuto, Kevin G. Yager
Summary: In this study, machine-guided discovery of emergent morphologies from a cylinder/lamellae block copolymer blend directed by a chemical grating template was demonstrated without direct human intervention on a synchrotron x-ray scattering beamline. This approach enables mapping of the morphology-template phase space in less time than manual characterization, and highlights regions that warrant further investigation. The results reveal localized, template-directed partitioning of coexisting lamella- and cylinder-like subdomains at the template period length scale, resulting in previously unknown morphologies such as aligned alternating subdomains, bilayers, or a ladder morphology. This work emphasizes the crucial role that autonomous characterization can play in advancing the paradigm of directed self-assembly (DSA).
Review
Nanoscience & Nanotechnology
Kevin G. Yager, Pawel W. Majewski, Marcus M. Noack, Masafumi Fukuto
Summary: Autonomous experimentation is an emerging paradigm that aims to automate the entire experiment workflow, including the decision-making step. By exploiting Gaussian process modeling and objective function, recent progress has been made in the application of this concept at synchrotron x-ray scattering beamlines. The automation of measurement instrument, data analysis, and decision-making, coupled with in situ processing platforms, facilitates efficient exploration of physical spaces and discovery of new materials.
Article
Chemistry, Physical
Samantha R. Nowak, Nikhil Tiwale, Gregory S. Doerk, Chang-Yong Nam, Charles T. Black, Kevin G. Yager
Summary: Blends of block copolymers are capable of responding to interfacial energy, allowing for the selection of pure or coexisting phases based on surface chemistry. This behavior stabilizes usually metastable structures, resulting in the generation of pure hexagonally perforated lamellar thin films across various thicknesses and surface energies. The responsiveness of the blend materials allows for the spatial definition of morphology through multi-tone chemical surface patterns.
Article
Chemistry, Multidisciplinary
Suwon Bae, Marcus M. Noack, Kevin G. Yager
Summary: This study investigates the ordering of diblock copolymers in thin films using coarse-grained molecular dynamics simulations, focusing on chain makeup, substrate surface energy, and surface tension disparity between the two constituent blocks. A machine-learning approach using a Gaussian process control algorithm is used to explore the parameter space and train a GP model that captures the system response and extracts material knowledge. It is found that the vertical orientation of BCP phases depends on multiple energetic contributions, including entropic and enthalpic material enrichment, distortion of morphological objects, and interfacial energies.
Article
Chemistry, Multidisciplinary
Kristof Toth, Chinedum O. Osuji, Kevin G. Yager, Gregory S. Doerk
Article
Materials Science, Multidisciplinary
Eli D. Kinigstein, Hsinhan Tsai, Wanyi Nie, Jean-Christophe Blancon, Kevin G. Yager, Kannatassen Appavoo, Jacky Even, Mercouri G. Kanatzidis, Aditya D. Mohite, Matthew Y. Sfeir
ACS MATERIALS LETTERS
(2020)