To celebrate the growth and development of the RSC Applied Polymers community and to highlight the remarkable authors who continue to contribute their high quality work to the journal, we would like to share the opinions and insights of these authors through this introductory blog post. Once dubbed #RSCAppliedfirst50, our blog posts aim to give a voice to the authors behind the research and hope that their insights might shed light upon growing challenges and progress in polymer science and its applications.
In this edition, we hear from Preeti Yadav, from the Okinawa Institute of Science and Technology Graduate University, as they discuss their recently published article, ‘Chloroform outperforms chlorobenzene for enhanced mobility in amphiphilic polymer OFETs‘.
An interview with Preeti Yadav
Can you tell us about the highlights of this study?
Our work demonstrates that OFET devices processed from chloroform, a volatile solvent, exhibited higher charge carrier mobility compared to those processed from chlorobenzene, challenging the conventional paradigm that high performance OFETs can be achieved only using low-volatility processing solvents. This breaks widely held beliefs where fast-drying solvents have generally been dismissed for device fabrication. This distinctive performance is enabled by the design of an amphiphilic polymer. A detailed analysis of polymer microstructure reveals that the improved charge mobility arises from differences in side-chain interactions in solution, which influences the polymer self-assembly during film formation leading to a microstructure more favourable for charge transport. In chloroform processed films, the relatively large crystallite size and uniform face-on orientation of crystallites contribute to enhanced mobility, even though chlorobenzene processed films exhibit greater local order, fewer crystal defects and mixed orientation. We hypothesize that chlorobenzene, due to its higher hydrophobicity exhibits a strong preference for hydrophobic side chains compared to chloroform, producing micelle like structures which interfere with polymer self-assembly thereby restricting the crystal growth and limiting the crystallite size. Overall, the amphiphilic polymer design approach coupled with unique solvent performance in this work offers new opportunities to address conventional processing limitations thereby establishing a foundation for designing next generation polymer systems and advancing innovation in sustainable technologies.
What aspect of your work are you most excited about at the moment?
Beyond the unexpected performance, our work establishes a new molecular design principle whereby the interplay between polymer amphiphilicity and processing solvent can be leveraged to control polymer self-assembly and ultimately device performance. Our study demonstrates an alternative strategy for enhancing charge carrier mobility and presents design guidelines for the development of polymers compatible with scalable and potentially sustainable fabrication of large-area organic electronic devices.
In your opinion, what are the most important questions to be asked/answered in your field of research?
The most important questions in the field of polymer-based electronics can be broadly grouped into three areas. First, can we develop predictive design rules that connect material structure and their properties to achieve optimal device performance instead of relying on empirical optimization? Although significant advances have been made in material development, we do not yet fully understand how molecular design and self-assembly can be used to precisely control polymer microstructure and approach the intrinsic performance limits of these materials. This could enable clearer molecular design guidelines and optimized device architecture that would lead to further improvement in carrier mobilities and other key performance metrics. Second, how can high-performance materials be realized while maintaining long-term operational stability, reproducibility and compatibility with scalable manufacturing process, all of which remain major barriers to real-world application of polymer-based technologies. Third, can we develop high-performance sustainable materials and environmentally friendly processing strategies that minimize environmental impact while remaining compatible with large-scale device fabrication? In our study, we contributed towards addressing these three challenges through the design of an amphiphilic copolymer. By incorporating amphiphilic side chains, we showed how controlling side-chain interactions in solution can influence the solution-state aggregation, self-assembly, resulting solid-state microstructure and device performance. Beyond this, the broader opportunity lies in identifying applications where polymer electronics can offer unique advantages that cannot be achieved with conventional inorganic semiconductor-based technologies.
What do you find most challenging in your work?
One of the things we find challenging is to understand the complex interplay between molecular design, solid-state microstructure and device performance in polymer materials. The resulting properties and device characteristics of these materials are governed not only by their chemical structure but also by microstructure and morphology, which are dictated by intermolecular interactions between polymer and solvent, and processing conditions. These relationships are difficult to predict and control because of the inherently complex nature of the polymer systems and even small changes can alter their performance. In addition, structural defects and batch to batch variations in material properties, which remain largely unavoidable despite advances in synthetic precisions can also significantly affect polymer microstructure and device characteristics. As a result, a major challenge is to identify which specific factors dominate the performance under competing influences through a thorough investigation and to understand how they can be controlled to establish universal design rules for development of high-performance polymer electronics.
Chloroform outperforms chlorobenzene for enhanced mobility in amphiphilic polymer OFETs
Preeti Yadav, Shunsuke Yamamoto, Kodai Yamanaka, Hengyuan Wang, Nadège Bonnet, Yabing Qi, Itaru Osaka and Christine K. Luscombe
RSC Appl. Polym., 2026, 4, 716-724. DOI: 10.1039/D5LP00320B
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