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Self-assembled membranes with uniform pore sizes tunable in 0.1-nm steps have been developed for organic solvent nanofiltration. 

Soft materials are usually defined as materials made of mesoscopic entities, often self-organised, sensitive to thermal fluctuations and to weak perturbations. Archetypal examples are colloids, polymers, amphiphiles, liquid crystals, foams. The importance of soft materials in everyday commodity products, as well as in technological applications, is enormous, and controlling or improving their properties is the focus of many efforts. From a fundamental perspective, the possibility of manipulating soft material properties, by tuning interactions between constituents and by applying external perturbations, gives rise to an almost unlimited variety in physical properties. Together with the relative ease to observe and characterise them, this renders soft matter systems powerful model systems to investigate statistical physics phenomena, many of them relevant as well to hard condensed matter systems. Understanding the emerging properties from mesoscale constituents still poses enormous challenges, which have stimulated a wealth of new experimental approaches, including the synthesis of new systems with, e.g. tailored self-assembling properties, or novel experimental techniques in imaging, scattering or rheology. Theoretical and numerical methods, and coarse-grained models, have become central to predict physical properties of soft materials, while computational approaches that also use machine learning tools are playing a progressively major role in many investigations. This Roadmap intends to give a broad overview of recent and possible future activities in the field of soft materials, with experts covering various developments and challenges in material synthesis and characterisation, instrumental, simulation and theoretical methods as well as general concepts. 

Lyotropic liquid crystals (LLCs) have drawn attention in numerous technical fields as they feature a variety of nanometer-scale structures, processability, and diverse chemical functionality. However, they suffer from poor mechanical properties and thermal stability. Polymerization in LLCs, referred to as LLC templating, is an effective approach to overcome this issue. While the templating approach results in robust mechanical, physical, and thermal properties, retention of the parent LLC structure after polymerization has been a major concern in the field. Therefore, there have been several efforts to introduce new materials and techniques to preserve the native LLC nanostructure after polymerization. In this review, we survey the efforts put in this area along with the applications of the obtained materials from LLC templating, after providing a brief introduction of LLC structures. Moreover, polymerization kinetics in different LLC structures, as a key player in the structure retention, are analyzed. Furthermore, we discuss the outlook of the field and available opportunities. 

A single-head/single-tail surfactant with a polymerizable group at each end is presented as a new simplified motif for intrinsically cross-linkable, gyroid-phase lyotropic mesogens. The resulting nanoporous polymer networks exhibit excellent structural stability in various solvents and are capable of molecular size discrimination. 

Reconfigurable arrays of 2D nanomaterials are essential for the realization of switchable and intelligent material systems. Using liquid crystals (LCs) as a medium represents a promising approach, in principle, to enable such control. In practice, however, this approach is hampered by the difficulty of achieving stable dispersions of nanomaterials. Here, we report on good dispersions of pristine CdSe nanoplatelets (NPLs) in LCs, and reversible, rapid control of their alignment and associated anisotropic photoluminescence, using a magnetic field. We reveal that dispersion stability is greatly enhanced using polymeric, rather than small molecule, LCs and is considerably greater in the smectic phases of the resulting systems relative to the nematic phases. Aligned composites exhibit highly polarized emission that is readily manipulated by field-realignment. Such dynamic alignment of optically-active 2D nanomaterials may enable the development of programmable materials for photonic applications and the methodology can guide designs for anisotropic nanomaterial composites for a broad set of related nanomaterials.

 

Bicontinuous cubic (Q) lyotropic liquid crystal (LLC)‐derived polymer networks possess periodic, uniform‐size, 3D‐interconnected nanopores that make them highly desirable organic materials for selective molecular separation and uptake applications. To date, there are no reported examples of a Q‐phase network with additional functional properties, such as catalytic reactivity, response to external stimuli, or gated transport, that would expand the usefulness of this class of porous materials. Here, a functionalized gyroid‐type Q polymer network material that can be used for potential gated transport or adaptive uptake applications is presented. This material contains a novel spiropyran‐containing dopant monomer that upon blending and cross‐linking with a gyroid‐forming LLC monomer, yields a gyroid polymer material that retains its phase architecture while reversibly responding to changes in external solution and vapor pH. Studies also demonstrate that this system is capable of strongly binding to aq. Pb²⁺ions when activated by UV light, allowing it to function as a potential colorimetric sorbent or gated‐response material.