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A versatile, stable, and highly air-tolerant triplet–triplet annihilation up-conversion system based on block copolymer micelles was designed and fabricated.

Self-assembly to build high-level structures, which is ubiquitous in living systems, has captured the imagination of scientists, striving to emulate the intricacy, homogeneity and versatility of the naturally occurring systems, and to pursue a similar level of organization in artificial building blocks. In particular, self-sorting assembly in multicomponent systems, based on the spontaneous recognition and consequent spatial aggregation of the same or interactive building units, is able to realize very complicated assembly behaviours, and usually results in multiple well-ordered products or hierarchical structures in a one-step manner. This highly efficient assembly strategy has attracted tremendous research attention in recent years, and numerous examples have been reported in artificial systems, particularly with supramolecular and polymeric building blocks. In the current review, we summarize the progress in recent years, and classify them into five main categories, based on their working mechanisms or principles. With the review of these strategies, we hope to provide not only some deep insights into this field, but also and more importantly, useful thoughts in the design and fabrication of self-sorting systems in the future.

Achieving full-color emission from a single chromophore is not only highly desirable from practical considerations, but also greatly challenging for fundamental research. Herein, we demonstrated the density-dependent emission colors from a single boron-containing chromophore, from which multi-color fluorescent polyurethanes were prepared as well. Originating from its switchable molecular conformations, the emission color of the chromophore was found to be governed by the packing density and strongly influenced by hydrogen bonding interactions. The chromophore was incorporated into polyurethanes to achieve full-color emitting materials; the emission color was only dependent on the chromophore density and could be tuned via synthetic approach by controlling the compositions. The emission colors could also be modulated by physical approaches, including by swelling/deswelling process, compression under high pressure, and even blending the fluorescent polyurethane with non-emitting ones.

A series of triphenylene esters with two ester groups at 2,3-, 2,7-, 2,6- and 3,6- substituent positions was successfully synthesized and fully investigated. Their self-assembly properties were exhaustively examined by DSC, POM, 1DXRD, 2DXRD, SAXS, TEM methods together with EDM and ESP calculations. It was unexpected that the 3,6-substituted triphenylene ester T5E36 formed an uncommonly helical hexagonal columnar superlattice structure made up of 91 right-handed helixes with a pitch of 60.3 A. This helical superlattice structure was further studied by using transmission electron microscopy and the diameter of the T5E36 particles was found to be at the nanometer scale. Ultimately, the bipolar charge carrier mobility was measured by the time-of-flight method to be in the order of 10−1 cm2 V−1 s−1. The formation of this helical superlattice nanostructure no doubt improved their electronic properties and made them more attractive in organic electronics.

The discotic liquid crystals composed of a rigid aromatic core and peripheral flexible side chains, are easy to be stacked into a one-dimensional ordered column structures by π–π interactions [1, 2, 3]. Although the discotic liquid crystals have been studied for many years, the research on discotic liquid crystal polymer (DLCP) is still fundamental, and its performance has not been studied widely in the fields of organic electronics and optoelectronics, such as the application of field-effect transistors, light-emitting diodes, and photovoltaic solar cells. To enrich the studies of the properties of discotic liquid crystal polymers, here we have successfully prepared poly {[3,6,7,10,11-pentakis(hexyloxy)-2-oxytriphenylene] methacrylate} (PMTS) via anionic polymerization for the first time. The chemical structure of the polymer was determined by FT-IR and 1H-NMR. The molecular weight of the polymer PMTS was characterized by Gel Permeation Chromatography (GPC). Its number average molecular weight was approximately 32,000 while its weight-average molecular weight was about 36000. The distribution of the molecular weight was 1.4. And then, their thermodynamics and liquid crystal properties were studied by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC).

A novel discotic liquid crystal donor-acceptor dyad was designed and synthesized based on triphenylene and perylene units, which was linked by a flexible alkyl chain. The mesogenic properties were investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM), and their chemical structures were determined by 1H-NMR and FT-IR. The discotic liquid crystal compound exhibited good mesomorphic properties and liquid crystal columnar phase properties, providing useful information for organic optoelectronic applications.

2D organic superlattice nanostructures of high charge carrier mobility of up to 8.1 × 10−2 cm2 V−1 s−1 were formed via hierarchical self-assembly of discotic liquid crystals as demonstrated by X-ray diffraction pattern and TEM. The supperlattice nanostructures, first reported by us, are expected to be used in optoelectronic devices such as OLEDs, OPVs and OFETs.

To reveal the relationships among molecular structures, self-assembly behavior and the organic electronic properties of discotic liquid crystals, 2-(neopentyloxy)-3,6,7,10,11-pentakis(pentyloxy)triphenylene (T5ON1) and 2-pivalate-3,6,7,10,11-penta-pentyloxy-triphenylene (T5EP1) have been synthesized based on hexapentyloxy-triphenylene (HAT5). Their mesomorphic properties were studied by differential scanning calorimetry (DSC), one-dimensional wide-angle X-ray diffraction (1D WAXD) and two-dimensional wide-angle X-ray diffraction (2D WAXD). T5ON1 and T5EP1 showed an ordered hexagonal columnar phase and a highly ordered hexagonal columnar plastic phase, respectively. To our surprise, Transmission Electron Microscope (TEM) images proved that a uniformly distributed superlattice nanostructure formed in the organic system of T5EP1. In addition, the hole and electron mobilities of T5EP1, which were 3.66 × 10−2 cm2 V−1 s−1 and 3.33 × 10−2 cm2 V−1 s−1, respectively, indicated that T5EP1 was a bipolar charge carrier transport material.

The highly ordered columnar plastic (Colhp) phase with charge carrier mobility up to 10−2 cm2 v−1 s−1 which is comparable to that of organic single crystals is considered as a potential charge transport material applied in electronic devices. The Colhp phase formed by monomers hexapropoxytriphenylene (HAT3) and hexabutoxytriphenylene (HAT4) as well as their corresponding symmetrical dimers can be supercooled into glassy states but with no monodomains obtained. It is expected that longer-lasting glassy states with monodomains can be engineered by making them subtly unsymmetrical. Unsymmetrical dimers with a Colhp phase can be constructed by the combination of any two of the three different monomers (HAT3, HAT4 and HAT5). Herein, three series of triphenylene-based dimers T3,4Dm, T4,5Dm, and T3,5Dm were synthesized by changing the spacer length (m = 6–12) and their mesophase was investigated by differential scanning calorimetry, polarizing optical microscopy, and wide-angle X-ray diffraction. These dimers can not only retain the order of the corresponding monomers but also obtain highly ordered single domains much more easily. To our surprise, the superlattice structure was firstly observed among these unsymmetrical dimers which made them not only be tractable models for discotic polymers with charge carrier mobility up to 10−2 cm2 v−1 s−1 but also provide a practical way for cultivating single crystals from discotic liquid crystals. The molecular stacking suggested that two different subunits tend to self-recognize and stack together, which was firstly reported by us and is very meaningful for supramolecular self-organization.

A novel triphenylene-based discotic liquid crystal 6-[3,6,7,10,11-Pentakis(pentyloxy)triphenylen-2-yloxy]-hexyl methacrylate. Chemical structure of this compound has determined by 1HNMR and FT-IR spectrum, and its mesophase was investigated by differential scanning calorimeter (DSC) and polarizing optical microscopy (POM) methods. This new compound has the unique optical properties of discotic liquid crystals because of their remarkable photoconductivity and high charge carrier mobility. Columnar discotic liquid crystals based on triphenylene show great potential as molecular organic materials for optoelectronic devices.

A novel triphenylene-based discotic liquid crystal 5-3,6,7,10,11-pentakispentyloxytriphenylen-2-yloxypentyl methacrylate was successfully synthesized. Chemical structure of this compound was determined by 1H-NMR and FT-IR spectrum, and its mesomorphism was investigated under the guidance of differential scanning calorimeter (DSC) and polarizing optical microscopy (POM) method. This compound apparently exhibited a classical texture of columnar phase in the mesophase temperature. The double bond on the side chain made it possible for this compound to be a candidate of designing and synthesizing liquid crystal polymer.

This study explored the effects of probucol on atherosclerotic plaques and soluble thrombomodulin in patients with coronary heart disease (CHD). Five hundred and eighty-three patients with CHD who were admitted to Jining First People's Hospital from February 2013 to February 2014. A total of 300 of them received conventional treatment, and were assigned to the control group, while the remaining 283 patients were treated with probucol in addition to the conventional treatment, and were assigned to the observation group. A retrospective analysis was performed on the total cholesterol levels, atherosclerotic plaque sizes, and soluble thrombomodulin levels. Probucol was administered at a dose of 500 mg twice a day for a period of 16 weeks. The total cholesterol level decreased gradually over time during the treatment. After 8 weeks of treatment, the total cholesterol level in the observation group was lower than that in the control group (P

The target product 2-hexylhexanoate-3,6,7,10,11-pentabutoxytriphenylene based molecules was synthesized and characterized. Several known experimental techniques had been used to determine the chemical structure, physical mesophase behavior of the compounds, by FT-IR spectroscopy, 1H-NMR, differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). By π-π stacking and dipole-dipole interaction, this compound can self-organize into columnar structures, providing useful information to organic optoelectronic applications.

A kind of new triphenylene-based liquid crystal 2-undecenoate-3,6,7,10,11-pentapentyloxytri-phenylene containing carbon-carbon double bonds was synthesized by esterification. The structure of the compounds was determined via 1HNMR and FT-IR spectroscopy. The thermal properties of the compound were studied in depth by differential scanning calorimeter (DSC) which showed a wide mesophase temperature from 113.8 °C to room temperature. The optical properties of the compound had also been studied by polarized light microscopy (POM) which showed a typical pyramid texture of the columnar phase. The derivative is expected to be used as polymerized monomers for the preparation of liquid crystal polymers via reversible addition chain transfer (RAFT) polymerization.

A series of discotic liquid crystals based on hexapentyloxytriphenylene (HAT5) have been investigated where one out of the six ether side chains of a triphenylene core was replaced by an ester side chain and named for 5a-5h. During the process of studying these compounds, the characteristic straight line defect of ordered columnar structure was identified by polarizing optical microscopy (POM) and liquid crystal state over a wide temperature range was obtained by differential scanning calorimetry (DSC). Basic phase structure and molecular arrangement were assigned by one-dimensional wide-angle X-ray diffraction (1D WAXD), small-angle X-ray scattering (SAXS), two-dimensional wide-angle X-ray diffraction (2D WAXD), and transmission electron microscope (TEM). Combined with sharp and regular dots in 2D WAXD patterns and characteristic peaks at small angle in SAXS pattern which indicated the existence of superlattice, we proved that 2D superlattice formed from self-assembly of discotic molecules with a polar group via π-π stacking and dipole-dipole interaction. In order to verify the effect of orientation on charge carrier mobility, their electron and hole mobilities were measured by time-of-flight (TOF) device, among which the charge carrier mobility could achieve almost twice as that of HAT5. The formation of superlattice no doubt improved their electronic properties and made them more attractive in organic electronics.

Correction for ‘Highly ordered columnar superlattice nanostructures with improved charge carrier mobility by thermotropic self-assembly of triphenylene-based discotics’ by Jingze Bi et al., J. Mater. Chem. C, 2019, 7, 12463–12469.