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In this account article, we give an overview of our contribution to the development of stable micellar carriers obtained by self-assembly and photo-polymerization of diacetylenic amphiphiles. The stabilized micelles can be loaded with active substances and used for diagnostic and therapeutic applications, or loaded with a metal catalyst to promote some synthetic transformations in fully aqueous medium. Table of content 1 Introduction 2 Polydiacetylene Micelles Applied to Nanomedicine 2.1 From Amphiphilic Units to Micelles 2.2 In vivo Behavior of Micelles 2.3 Passive Targeting of Tumors with Micelles 2.4 Drug Delivery with Micelles 2.5 Towards Improved Delivery of Micelles to Tumors Using Sonoporation 2.6 Active Targeting with Micelles 2.7 Behavior of Micelles at the Cellular Level and Potential Cytotoxicity 2.8 Micelles for siRNA Transfection 3 Polydiacetylene Micelles Applied to Catalysis 3.1 Copper Nanoparticles in Micelles 3.2 Copper Salts in Micelles 4 Conclusion [ABSTRACT FROM AUTHOR]

Solvatochromism plays a pivotal role in various scientific and technological fields including those that explore molecular interactions, sensing technologies, and organic electronics. Notably, despite their ease of manipulation, direct visualization, and potential for single particle‐based sensing, micro‐sized solid particles have been the focus of a surprisingly low number of solvatochromism investigations. In this study, polydiacetylene (PDA) particles are synthesized and their solvatochromism is investigated at the single particle level using optical laser tweezers‐based methods. The findings reveal that unpolymerized monomers within PDA particles at the water/n‐decane interface undergo dissolution in the n‐decane phase to form internal voids in the particles. This phenomenon leads to structural deformation of the PDA which triggers a solvatochromic response. Studies that integrate this phenomenon with established particle‐based methodologies should provide deeper insights into diverse chromism behaviors and potential applications of solvatochromic materials. [ABSTRACT FROM AUTHOR]

In the present study, electrospinning of polyvinylpyrrolidone (PVP) and polydiacetylene (PDA) with pomegranate peel (PG) extract was investigated for the preparation of smart and antibacterial nanofibers. Briefly, PDA-PVP solutions were firstly prepared at two different ratios and electrospun under different conditions. Based on the SEM results, the 1:3 ratio of PDA:PVP nanofibers, with an average fiber diameter of 130 ± 40 nm, electrospun at a voltage of 15 kV, feeding rate of 0.5 ml/h and collector distance of 15 cm was selected as the optimal conditions. The addition of PG resulted in an increase in the diameter of the fibers. The color of the electrospun fibers was altered from blue to red due to changes in either temperature or pH or exposure to different solvents. The antibacterial test showed high antimicrobial activity of the fibers loaded with PG extract against both S. aureus and E. coli. MTT assay and cell attachment also validated the biocompatibility of the fabricated nanofibers. Thus, the prepared smart PG-loaded nanofibers had a high potential to be used in wound dressing applications. [ABSTRACT FROM AUTHOR]

Functional supramolecular materials exhibit important features including structural versatility and versatile applications. Here, this study reports the construction of unique hierarchically organized nanotoroids exhibiting fluorescence, photocatalytic, and sensing properties. The nanotoroids comprise of macrocyclic diacetylenes (MCDA) and 8‐anilino‐1‐naphthalene sulfonate (ANS), a negatively charged aromatic fluorescent dye. This study shows that the hierarchical structure of the nanotoroids consist of MCDA nanofibers formed by stacked diacetylene monomers as the basic units, which are further bent and aligned into toroidal organization by electrostatic and hydrophobic interactions with the ANS molecules. The amine moieties on the nanotoroids surface are employed for deposition of gold nanostructures – Au nanoparticles or Au nanosheets – which constitute effective platforms for photocatalysis and surface enhanced Raman scattering (SERS)‐based sensing. [ABSTRACT FROM AUTHOR]

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene (PDA) materials have always been a challenging issue. In this work, a series of diacetylene monomers (m-PCDA) containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid (PCDA) through the esterification or amidation reactions. The effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability, and the thermochromic mechanism of their corresponding polymers (m-PDA) were investigated and discussed in detail. The results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction, and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA materials. The thermochromic behavior of m-PDA depends on its melting process. The initial color-change temperature (blue to red) is determined by the onset melting temperature, and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting range. According to the proposed thermochromic mechanism of PDA, various new PDA materials with precise thermochromic temperatures and reversible thermochromic temperature ranges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene monomer. This work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials. [ABSTRACT FROM AUTHOR]

Polydiacetylene (PDA) is a kind of photopolymerizable polymer, which exhibits a unique color transition in response to external stimuli such as heat, pH, and solvent. PDAs are attractive as eye‐detection stimulus sensors with excellent time performance; however, the sensitivity of PDAs should be improved. Considering the biological membrane‐like structure of diacetylene (DA) vesicles, their modification by incorporating membrane lipids (e.g., diacylphosphocholine, PC) can be used to control the membrane fluidity, and consequently molecular ordering of DAs in the vesicle. Inspired by biological membrane systems, lipid vesicles are employed as platforms to generate PDA, and essential factors that influence the sensitivity of PDA are investigated. By lowering the polymerization temperature, the generation of PDA becomes slower, while the sensitivity improves. By adding PCs at the molar ratio of lipid:DA = 1:1, the sensitivity of PDA can be varied: the PCs with lower phase transition temperatures (Tm) made PDA insensitive, while the PCs with higher Tm improved the sensitivity as compared to pure poly(PCDA). It is concluded that the photopolymerization of DAs with a lower membrane fluidity induces highly sensitive PDA, while the photopolymerization of DAs with a higher membrane fluidity induces insensitive PDA with robustness toward stimuli. [ABSTRACT FROM AUTHOR]

This study develops a vitamin C controlled-release system, trackable via color changes as a function of vitamin C release. The system is composed of coaxial microfibers prepared via coaxial electrospinning, with a core of poly(ethylene oxide) (PEO) incorporating vitamin C, and a shell composed of polycaprolactone (PCL) containing polydiacetylene (PDA) as the color-changing material. The shell thickness is controlled by adjusting the amount of PCL ejected during electrospinning, allowing regulation of the release rate of vitamin C. When vitamin C added to PEO penetrates the PCL layer, the color of PDA changes from blue to red, indicating a color change. The results of this study can be applied to devices that require immediate detection of vitamin C release levels. [ABSTRACT FROM AUTHOR]

Colorimetric chemical sensing of target gases, such as hydrogen peroxide vapors, is an evolving area of research that implements responsive materials that undergo molecule-specific interaction, resulting in a visible color change. Due to the intuitive nature of an observable color change, such sensing systems are particularly desirable as they can be widely deployed at low cost and without the need for complex analytical instrumentation. In this work, we describe our development of a new spray-on sensing material that can provide a colorimetric response to the presence of a gas-phase target, specifically hydrogen peroxide vapor. By providing a cumulative response over time, we identified that part per million concentrations of hydrogen peroxide vapor can be detected. Specifically, we make use of iron chloride-containing formulations to enable the catalysis of hydrogen peroxide to hydroxyl radicals that serve to initiate polymerization of the diacetylene-containing amphiphile, resulting in a white to blue color transition. Due to the irreversible nature of the color change mechanism, the cumulative exposure to hydrogen peroxide over time is demonstrated, enabling longitudinal assessment of target exposure with the same coatings. The versatility of this approach in generating a colorimetric response to hydrogen peroxide vapor may find practical applications for environmental monitoring, diagnostics, or even industrial safety. [ABSTRACT FROM AUTHOR]

Solvatochromism plays a pivotal role in various scientific and technological fields including those that explore molecular interactions, sensing technologies, and organic electronics. Notably, despite their ease of manipulation, direct visualization, and potential for single particle‐based sensing, micro‐sized solid particles have been the focus of a surprisingly low number of solvatochromism investigations. In this study, polydiacetylene (PDA) particles are synthesized and their solvatochromism is investigated at the single particle level using optical laser tweezers‐based methods. The findings reveal that unpolymerized monomers within PDA particles at the water/n‐decane interface undergo dissolution in the n‐decane phase to form internal voids in the particles. This phenomenon leads to structural deformation of the PDA which triggers a solvatochromic response. Studies that integrate this phenomenon with established particle‐based methodologies should provide deeper insights into diverse chromism behaviors and potential applications of solvatochromic materials.

Colorimetric detection of long chain fatty acids by polydiacetylenes (PDAs)-based sensors is quite a challenge, mainly due to their relatively low solubility in aqueous media. In this study, we developed PDA/Zn2+/ZnO nanocomposites in various organic solvents for detecting fatty acids. Oleic acid and steric acid were used as representatives of fatty acids with bent and linear structures, respectively. The nanocomposites dispersed in ethanol exhibited blue-to-red color transition upon increasing the concentration of oleic acid. The use of other solvents including 1-butanol, 1-hexanol, 1-octanol, 1,4-dioxane, hexane, octane and toluene affected the sensitivity of nanocomposites. Furthermore, incorporating cetyltrimethylammonium bromide (CTAB) into the structure of the nanocomposites resulted in a systematic increase of sensitivity. The use of organic solvents simplified the method and allowed direct sensing of the fatty acids. Paper-based sensor was fabricated and utilized as a mobile test kit. This class of colorimetric sensors can also distinguish the bent and linear structures of fatty acids. Our study extends the utilization of PDA-based materials as colorimetric sensors of fatty acids in food industries.

A novel platform of a polydiacetylene combined with rhodamine B (PDA-Rho) colorimetric chemosensor array was prepared from a diacetylene monomer and rhodamine B derivative. Rhodamine B derivative as the ion-recognition element was embedded in the polydiacetylene matrix. To fabricate chemosensor, diacetylene monomer connected rhodamine B derivatives (DA-Rho) was coated onto a filter paper surface via drop-casting technique and transformed to polydiacetylene by polymerisation through ultraviolet (UV) irradiation. From the result, PDA-Rhoen exhibited high sensitivity and selectivity for Au3+ and could be monitored directly by naked eyes providing a fast, portable and easy-to-use as a molecular device in the real system. The DFT calculation results showed a stable complex between PDA-Rho and Au3+. We believe that, this method offers a sensitive and accurate process for Au3+ ion detection in real environmental and biological applications. [ABSTRACT FROM AUTHOR]

The development of smart materials with reversible thermochromic properties is of great importance in the fields of sensors, displays and anticounterfeitings. In this article, a diacetylene monomer (AQDA) containing aminoquinoline as a head group was synthesized. Together with fluorescein-substituted diacetylene (FDA) and 10,12-pentacosadiynoic acid (PCDA), hybrid PDA vesicles were obtained through self-assembly and topochemical polymerization process. The hybrid PDA vesicles (FDA, AQDA and PCDA with molar ratio of 7:2:1) display an partially reversible green-to-orange red colorimetric change in a wider temperature range from 20 to 100 °C focusing on the stronger hydrogen bonding and aromatic interactions. This work may provide fundamental understanding of the mechanism and strategies for the design of reversible thermochromic PDA materials. [ABSTRACT FROM AUTHOR]

Polydiacetylene (PDA) has been actively employed as sensing vehicles owing to its unique colorimetric feature upon environmental stimulation. Here, blue phase PDA has been constructed by topological polymerization of commercial diacetylene acid (DA) noncovalently modified by guest amines. Specifically, PDA including 1‐naphthylmethylamine noncovalently bonded on both sides exhibits long‐term stability in polar organic solvents. The stability of PDA depended upon both the structures of the DA and the guest molecule, underscoring a stabilizing mechanism dominated by noncovalent bonding and strong π–π interaction. Accordingly, the blue phase PDA shows a colorimetric response from blue to red upon exposure to stimuli influencing noncovalent bonding and π–π interaction, such as elevated temperature, the existence of acid or alkali at concentrations as low as 50 ppm. Therefore, the PDA developed in this study has the potential of serving as a colorimetric sensor for detecting subtle environment changes and especially for measuring the quality of polar organic solvents recovered from industrial effluent. [ABSTRACT FROM AUTHOR]

Food waste is a huge problem worldwide, and spoilage during storage is a major contributor. Food freshness monitoring systems can help reduce food waste by providing consumers with information to more accurately predict the shelf life of their food. In the case of milk, pH can be used as a freshness indicator. As milk spoils, microbial activity converts lactose to lactic acid, which produces hydrogen ions (H+) and consequently lowers the pH of the milk. In this paper, we propose a paper sensor that can detect the pH of milk in a refrigerated state (− 4 ℃) by color change. Polydiacetylene (PDA)/zinc oxide (ZnO) nanocomposite, which changes its color from blue to red as the pH decreases, was used as the color changing material. Specifically, the nanocomposite was applied to a nitrocellulose (NC) membrane, which is approved as a food packaging material for monitoring freshness during transport or on the shelf. The freshness monitoring function of the sensor was verified by applying artificially spoiled milk samples to the PDA/ZnO@NC membrane. In particular, it was demonstrated that the PDA/ZnO@NC membrane was shown to detect spoiled milk samples with pH 4.5 in 10 min at low temperature. Furthermore, the color change of the sensor upon detection of spoilage remained stable even after long-term storage. In conclusion, the PDA/ZnO@NC membrane presented in this study can be widely applied to the freshness monitoring of various food products stored at low temperatures whose spoilage is evaluated by pH. [ABSTRACT FROM AUTHOR]

2D polydiacetylene (PDA) layered composites with added guest molecules have demonstrated an excellent tunable mechanochromic properties toward the development of mechanochromic force sensors in energy‐related and medical applications. However, its force sensitivity at the nanoscale is left uncharacterized due to a lack of technique to conveniently apply forces to the 2D films in different directions, limiting the quantitative understanding of the sensitivity‐tuning mechanism. In this work, the quantitative friction force microscopy combined with fluorescence microscopy is introduced to measure the force sensitivity of the PDA layered composites with guest organic amines at the nanoscale. Intercalating nonylamine and 1‐aminodecane increase the sensitivity of 10,12‐pentacosadiynoic acid by 127% and 111%, respectively, whereas adding n‐tridecaylamine and stearylamine reduce it by 77% and 86%. This force sensitivity at the nanoscale is inversely correlated to the thermochromic temperature and the Young's moduli of the films, suggesting that the softer film has both higher force‐ and thermo‐sensitivity. [ABSTRACT FROM AUTHOR]

There are different methods used for the determination of antimicrobial activity of bacteriocins. The most commonly used are the disk-diffusion and dilution methods. The other methods such as point inoculation method, agar overlay assay, cross streak method, radial streak method, agar plug diffusion method, spot-on-lawn assay, Oxford cup method, agar well diffusion assay, and vesicle-based colorimetric assay are also used for the determination of antimicrobial activity of bacteriocins. The inhibitory effect of bacteriocins is dependent on time, concentration and type of bacteriocins. The antimicrobial activity is also dependent on the solid or liquid medium used for the growth of indicator bacteria. A vesicle-based assay which is indicator-independent has also been used for the detection of antimicrobial activity of bacteriocins. In this review, we have discussed the conventional and modern methods which are indicator-dependent and -independent for the detection of bacteriocins and high-throughput screening of bacteriocin-producing strains of lactic acid bacteria. [ABSTRACT FROM AUTHOR]

Polydiacetylenes (PDAs) are a family of highly conjugated polymers that generate optical response sensitively if exposed to stimuli, the color would change from blue to red. PDAs with reusability and color reversibility are at the central of current research efforts generously. They enhance the electrostatic interaction between cations and the negatively charged carboxylate head groups to increase the rigidity and decrease the energy barrier by introducing Ni2+ into the side chains of PDAs. The amphiphilic 10,12‐pentacosadiynoic acid (PCDA) molecules with the hydrophilic and hydrophobic group are dispersed into Ni2+ aqueous solution and self‐assembled in situ into nanoparticles. Transferring the solution onto a paper base to yield a precisely controlled thickness of PDAs thermal paper. The thermal paper undergoes UV‐induced topological chemical polymerization and further cross‐linking to form stably blue. Because of the reduced energy barrier, red thermal paper after thermal stimulation can undergo color reduction under UV light irradiation. Increasing the photopolymerization time from 5 s to 600 s leads to the rising of the color change temperature from approximately 76.4 °C to 105.4 °C. The polydiacetylene/Ni2+ (PDA/Ni2+) thermal paper can be available for green printing, thermal history recording, and temperature visualization. [ABSTRACT FROM AUTHOR]

Fundamental physical chemical properties of a monolayer film comprised of the chiral, photopolymerizable phospholipid 1,2‐bis(10,12‐tricosadiynoyl)‐sn‐glycero‐3‐phosphocholine (Diyne PC) and the impact of a model perfluorocarbon, perfluorotetradecanoic acid (PF), on these film properties have been investigated, both with and without UV photopolymerization. Enantiomerically pure Diyne PC formed compact, stable monolayers at the air‐water interface, exhibited typical phospholipid phase transitions in surface pressure‐area isotherms and yielded micron‐scale, linear domains upon film compression. Photopolymerized films were significantly more expanded in comparison with the unpolymerized films and the resulting domains had a spiral morphology with a strongly preferred spiral direction. Mixing Diyne PC with PF altered the isotherm behavior, with the principal effects being a significant reduction in the plateau region associated with the characteristic LE‐LC phase transition and no larger‐scale spiral domain formation in the monolayers of the mixed films. Results are discussed in the context of interactions between the two different film components and the tendency of perfluorinated surfactants to disperse condensed phase regions of phospholipid‐based monolayer films. Overall, the tendency of PF to disperse condensed regions of the film makes patterning of films in mixed phospholipid‐perfluorocarbon monolayers particularly difficult. [ABSTRACT FROM AUTHOR]

Polydiacetylenes (PDAs), conjugated and stimuli-responsive polymers, are of interest for colorimetric sensing technologies. Commercially available PDAs with carboxylic headgroup do not show any colorimetric response to acid. To achieve acid-responsive property, the headgroups of PDAs are often modified with some functional moieties, involving complicated synthetic processes. This contribution presents a facile approach to develop acid-responsive materials via co-assembly of PDA and excess sodium hydroxide (NaOH). After low-temperature incubation and photopolymerization, the mixtures of 10,12-tricosadiynoic acid (TCDA) and NaOH develop into red-phase poly (TCDA-Na+) assemblies. A unique red-to-blue color transition occurs when the poly (TCDA-Na+) assemblies are exposed to hydrogen chloride (HCl) acid both in aqueous solution and gas phase. Increasing the concentrations of NaOH and TCDA monomer during the self-assembly process affects the molecular organization and morphologies of the resultant poly (TCDA-Na+) assemblies, which in turn govern the sensitivity to acid. The results of this study offer a simple and inexpensive method for developing acid-responsive PDAs, extending their colorimetric sensing applications.

This study develops a vitamin C controlled-release system, trackable via color changes as a function of vitamin C release. The system is composed of coaxial microfibers prepared via coaxial electrospinning, with a core of poly(ethylene oxide) (PEO) incorporating vitamin C, and a shell composed of polycaprolactone (PCL) containing polydiacetylene (PDA) as the color-changing material. The shell thickness is controlled by adjusting the amount of PCL ejected during electrospinning, allowing regulation of the release rate of vitamin C. When vitamin C added to PEO penetrates the PCL layer, the color of PDA changes from blue to red, indicating a color change. The results of this study can be applied to devices that require immediate detection of vitamin C release levels.

Colorimetric chemical sensing of target gases, such as hydrogen peroxide vapors, is an evolving area of research that implements responsive materials that undergo molecule-specific interaction, resulting in a visible color change. Due to the intuitive nature of an observable color change, such sensing systems are particularly desirable as they can be widely deployed at low cost and without the need for complex analytical instrumentation. In this work, we describe our development of a new spray-on sensing material that can provide a colorimetric response to the presence of a gas-phase target, specifically hydrogen peroxide vapor. By providing a cumulative response over time, we identified that part per million concentrations of hydrogen peroxide vapor can be detected. Specifically, we make use of iron chloride-containing formulations to enable the catalysis of hydrogen peroxide to hydroxyl radicals that serve to initiate polymerization of the diacetylene-containing amphiphile, resulting in a white to blue color transition. Due to the irreversible nature of the color change mechanism, the cumulative exposure to hydrogen peroxide over time is demonstrated, enabling longitudinal assessment of target exposure with the same coatings. The versatility of this approach in generating a colorimetric response to hydrogen peroxide vapor may find practical applications for environmental monitoring, diagnostics, or even industrial safety.

Abstract 2D polydiacetylene (PDA) layered composites with added guest molecules have demonstrated an excellent tunable mechanochromic properties toward the development of mechanochromic force sensors in energy‐related and medical applications. However, its force sensitivity at the nanoscale is left uncharacterized due to a lack of technique to conveniently apply forces to the 2D films in different directions, limiting the quantitative understanding of the sensitivity‐tuning mechanism. In this work, the quantitative friction force microscopy combined with fluorescence microscopy is introduced to measure the force sensitivity of the PDA layered composites with guest organic amines at the nanoscale. Intercalating nonylamine and 1‐aminodecane increase the sensitivity of 10,12‐pentacosadiynoic acid by 127% and 111%, respectively, whereas adding n‐tridecaylamine and stearylamine reduce it by 77% and 86%. This force sensitivity at the nanoscale is inversely correlated to the thermochromic temperature and the Young's moduli of the films, suggesting that the softer film has both higher force‐ and thermo‐sensitivity.

This study aims to produce smart nanocomposite fibers using the electrospinning method for potential sensing applications. For this purpose, polyvinylpyrrolidone (PVP) and polydiacetylene (PDA) solutions at two different ratios are prepared and electrospun at the voltage of 15 kV, distance to the collector of 15 cm, and the flow rate of 1 mL/h. To enhance the mechanical properties and sensitivity of the fibers, graphene oxide (GO) is then added to the polymer solution at different percentages of 0.5 to 2 wt%, and electrospinning is performed under the optimized conditions. Based on SEM analysis, with increasing the percentage of GO, the average fiber diameter decreases from 180 nm (without graphene) to 150 nm (1.5 wt% GO) due to the higher conductivity of the polymer solution after incorporation of GO. FTIR spectra reveal the possible hydrogen bonding between the components. In order to investigate the colorimetric behavior of the electrospun nanofibers, they are subjected to various temperatures and pHs, and a color change from bluish‐purple to reddish‐pink is observed due to conformational changes in PDA macromolecules. Finally, DSC results confirm the higher thermal stability of the nanocomposite fibers containing GO. Therefore, the fabricated thermochromic nanofibers are potentially appropriate candidates as sensors. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) can be generated from chiral luminescent materials. It can also be achieved from achiral emissive dyes by selectively filtering their fluorescence with chiroptical active materials. In this work, a novel polydiacetylene‐based supramolecular chiral gel is fabricated as a handedness‐selective fluorescence filter for generating CPL. The gelator consists of a diacetylene alkyl chain and a chiral histidine (His) head group (HisDA). It can self‐assemble into nanoribbon and turn into the blue phase, purple phase and red phase polydiacetylene‐His (HisPDA) upon photopolymerization. The resulting L/D‐HisPDA gels show variable circular dichroism (CD) with the change in color. Furthermore, multiple CPL signals are achieved after fluorescence excited with achiral dyes D1–D3 passing through HisPDA gel. The intensity of CPL increases gradually in both D1 and D3 dye systems along with the change of the HisPDA gel from blue phase to red phase, while the CPL signal is inverted for the D2 dye system. The handedness of the CPL signal is opposite to the CD signal of HisPDA gel in all the cases, demonstrating that CPL is originated through a handedness‐selective fluorescence adsorption mechanism. This study offers a new strategy for obtaining tunable CPL via adjustable chiral fluorescence filters. [ABSTRACT FROM AUTHOR]

Circularly polarized light (CPL) has attracted considerable interest since it can impart chiral bias into photochemical reactions and open up a novel opportunity for synthesizing chiral polymer materials. Despite numerous reports describing the chiral induction effect with single CPL, the synergistic or competitive effect between two types of CPL—i.e., circularly polarized ultraviolet light (CPUV) for triggering asymmetric polymerization while circularly polarized visible light (CPVL) only for accelerating helical chain propagation—is rarely reported. Here, this work demonstrates that the selective regulation on the asymmetric photopolymerization can be realized by the arbitrarily coupled irradiation with CPUV and CPVL, either constructively or destructively. In the former case, further chirality amplification can be achieved. Remarkably, for the latter case, the opposite handed CPVL can bias the polymer helicity during the chain propagation process and thereby overrule the helical preference inducted by CPUV. This work highlights the importance of chiral induction effect in helical chain propagation process and is highly valuable for deeper understanding of helical preference in CPL‐triggered asymmetric photopolymerization. [ABSTRACT FROM AUTHOR]

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Sprayable stimuli-responsive material coatings represent a new class of detection system which can be quickly implemented to transform a surface into a color-responsive sensor. In this work, we describe a dipicolylamine-terminated diacetylene-containing amphiphile formulation for spray coating on to a simple paper substrate to yield disposable test strips that can be used to detect the presence of lead ions in solution. We find the response to be very selective to only lead ions and that the sensitivity can be modulated by altering the UV curing time after spraying. Sensitive detection to at least 0.1 mM revealed a clear color change from a blue to red phase. This represents the first demonstration of a spray-on sensor system capable of detection of lead ions in solution. [ABSTRACT FROM AUTHOR]

Organic supercapacitors are considered attractive alternatives to traditional inorganic‐based charge storage devices due to their synthetic versatility, low cost, and environment‐friendliness features. Photopolymerized anthraquinone‐polydiacetylene is employed as a core component in high‐performance asymmetric supercapacitors (ASCs). Specifically, interspersed polydiacetylene‐anthraquinone/polyaniline (PANI) electrodes are prepared via drop‐casting and used as cathodes in devices employing polypyrrole/reduced graphene oxide anodes using aqueous or ionic liquid electrolytes. The excellent electrochemical properties of the polydiacetylene‐anthraquinone/PANI electrodes, specifically high capacitance (specific capacitance ≈720 F g−1 at 1 A g−1), long discharge time, and cycling stability, are ascribed to the superior redox profile of the anthraquinone and ambipolar charge transport associated with the polydiacetylene framework. The asymmetric supercapacitor prepared using the polydiacetylene‐anthraquinone/PANI electrodes displays a high energy density of 36 Wh kg−1 at a power density of 995 W kg−1, underscoring possible utilization of the anthraquinone‐polydiacetylene derivative in practical energy storage devices. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of a new representative of hemicurcuminoids with a nonyloxy substituent (HCur) as a fluorescent amphiphilic structural element of vesicular aggregates based on phosphatidylcholine (PC), phosphatidylserine (PS), and 10,12-pentacosadiynoic acid (PCDA). Both X-ray diffraction analysis of the single crystal and 1H NMR spectra of HCur in organic solvents indicate the predominance of the enol-tautomer of HCur. DFT calculations show the predominance of the enol tautomer HCur in supramolecular assemblies with PC, PS, and PCDA molecules. The results of the molecular modeling show that HCur molecules are surrounded by PC and PS with a rather weak exposure to water molecules, while an exposure of HCur molecules to water is enhanced under its supramolecular assembly with PCDA molecules. This is in good agreement with the higher loading of HCur into PC(PS) vesicles compared to PCDA vesicles converted into polydiacetylene (PDA) ones by photopolymerization. HCur molecules incorporated into HCur-PDA vesicles exhibit greater planarity distortion and hydration effect in comparison with HCur-PC(PS) ones. HCur-PDA is presented as a dual fluorescence-chromatic nanosensor responsive to a change in pH within 7.5–9.5, heavy metal ions and polylysine, and the concentration-dependent fluorescent response is more sensitive than the chromatic one. Thus, the fluorescent response of HCur-PDA allows for the distinguishing between Cd2+ and Pb2+ ions in the concentration range 0–0.01 mM, while the chromatic response allows for the selective sensing of Pb2+ over Cd2+ ions at their concentrations above 0.03 mM. [ABSTRACT FROM AUTHOR]

Imaging and measuring compression stresses secure a safe and healthy life. Compression stresses in kPa range are not easily detected by conventional mechanoresponsive materials because microscopic molecular motion of the chromophores is not induced by such weak stresses. Moreover, imaging of the stress distribution is not achieved so far. The present study shows a sponge device combining two stimuli‐responsive materials, a capsule releasing interior liquid and color‐changing polymer in responses to compression stress and chemical stimulus, respectively. The stimuli‐responsive capsule is dispersed on a melamine sponge comprised of the fibers with coating the layered polydiacetylene (PDA). The application of weak compression stresses induces collapse of the capsules, outflow of the interior liquid, and subsequent irreversible color change of PDA. The cascading response in the sponge device colorimetrically enables imaging of the distribution and measuring the strength of the compression stresses in kPa range. Furthermore, the device demonstrates imaging and measuring unknown weak compression stresses applied by the irregular‐shaped objects. A couple of clinical issues in surgical operation of intestine are studied using the stress‐imaging sponge device. The device and its design strategy can be applied to stress imaging in a variety of fields. [ABSTRACT FROM AUTHOR]

Polyarylene ether nitrile (PEN) is a novel high-performance engineering plastic with various applications, particularly in thermoresistance-required fields. In this study, a well-known stimuli-response polydiacetylene monomer, 10, 12-pentacosadiynoic acid (PCDA), was encapsulated within electrospun PEN nanofibers to fabricate a colorimetric membrane with satisfactory thermal and corrosion resistance. To optimize the compatibility with PCDA, two PENswith distinct molecular chains were utilized: PEN−PPL and PEN−BPA. The chemical structure and elemental mapping analysis revealed that the PCDA component was successfully incorporated into the PEN fibrous. The PCDA bound significantly better to the PEN−PPL than to the PEN−BPA; due to the carboxyl groups present on the side chains of PEN−PPL, the surface was smooth and the color changed uniformly as the temperature rose. However, owing to its poor compatibility with PEN−BPA, the PCDA formed agglomerations on the fibers. The thermal analysis demonstrated that the membranes obtained after PCDA compounding maintained their excellent heat resistance. The 5% weight loss temperatures of composite nanofibrous membranes manufactured by PEN−PPL and PEN−BPA were 402 °C and 506 °C, respectively, and their glass transition temperatures were 219 °C and 169 °C, respectively, indicating that the blended membranes can withstand high temperatures. The evaluation of application performance revealed that the composite membranes exhibited good dimensional stability upon high thermal and corrosive situations. Specifically, the PEN−P−PCDA did not shrink at 170 °C. Both composite membranes were dimensionally stable when exposed to the alkali aqueous solution. However, PEN−P−PCDA is more sensitive to OH−, exhibiting color transition at pH > 8, whereas PEN−B−PCDA exhibited color transition at high OH− concentrations (pH ≥ 13), with enhanced alkali resistance stability owing to its nanofibrous architecture. This exploratory study reveals the feasibility of PEN nanofibers functionalized using PCDA as a desirable stimulus-response sensor even in high-temperature and corrosive harsh environments. [ABSTRACT FROM AUTHOR]

Here, a benzaldehyde substituted diacetylene vesicle formed through a self‐assembly strategy in water is reported. Under UV irradiation, conjugated polydiacetylene (PDA) could be generated in the blue phase by 1,4‐addition topopolymerization. Furthermore, this newly developed PDA vesicle displays distinctive colorimetric response to triple stimuli, including temperature, pH, and organic amines. Specifically, a clear blue‐to‐purple‐to‐red chromatic transition is observed for the PDA vesicle upon a gradient heating procedure from 25 to 75 °C. Although no obvious colorimetric changes happen when the PDA vesicle is exposed to acidic environments, it gradually turns into red color in alkaline aqueous solution or atmosphere with increasing pH values. More interestingly, this PDA vesicle can serve as an excellent sensor to distinguish some typical aliphatic/aromatic amines based on its different colorimetric and morphologic transformation behaviors. It is suggested that the incorporated benzaldehyde head group in PDA plays an essential role for the resulting responsiveness to the various environmental stimuli. As the preparation method is simple and straightforward, the novel PDA vesicle introduced here holds great potential as a promising sensor with the naked eye. [ABSTRACT FROM AUTHOR]

Abstract Imaging and measuring compression stresses secure a safe and healthy life. Compression stresses in kPa range are not easily detected by conventional mechanoresponsive materials because microscopic molecular motion of the chromophores is not induced by such weak stresses. Moreover, imaging of the stress distribution is not achieved so far. The present study shows a sponge device combining two stimuli‐responsive materials, a capsule releasing interior liquid and color‐changing polymer in responses to compression stress and chemical stimulus, respectively. The stimuli‐responsive capsule is dispersed on a melamine sponge comprised of the fibers with coating the layered polydiacetylene (PDA). The application of weak compression stresses induces collapse of the capsules, outflow of the interior liquid, and subsequent irreversible color change of PDA. The cascading response in the sponge device colorimetrically enables imaging of the distribution and measuring the strength of the compression stresses in kPa range. Furthermore, the device demonstrates imaging and measuring unknown weak compression stresses applied by the irregular‐shaped objects. A couple of clinical issues in surgical operation of intestine are studied using the stress‐imaging sponge device. The device and its design strategy can be applied to stress imaging in a variety of fields.

Antibiotic resistance is a global public health issue, accelerated by the misuse and overuse of antibiotics. Microenvironment-targeted antimicrobial delivery is an emergent and promising strategy for selective antibiotic delivery that targets the site of infections and may reduce drug resistance. The local pH of infected tissues can be a primary target for designing materials with pH-triggered antimicrobial activity. Given the urgent need to combat bacterial infections in diseases with an elevated pH, we report on the design and synthesis of a new alkaline-responsive antimicrobial hydrogel. The gels are based on a polydiacetylene-peptide (PDA-Pep) having pH-dependent molecular and macromolecular structure and packing. Upon pH elevation, the peptide domain is deprotonated and triggers the conformational change of the PDA domain, leading to a colorimetric transition from blue to purple. Simultaneously, the deprotonation induces a gel-to-sol macroscopic phase transition of the fiber network formed in PDA-Pep hydrogels, which causes the selective release of the antimicrobial agents that are encapsulated in the gels into the infection site to kill bacteria. The translational potential of PDA-Pep hydrogels for pH-sensing and on-demand alkaline-triggered antibiotic delivery was demonstrated on inoculated pig skins. The work lays the foundation for the development of multifunctional alkaline-responsive materials in which multiple small molecule or macromolecular therapeutics can be encapsulated to achieve synergistic biological functions against a wide range of multidrug-resistant pathogens.

Creation of new two‐dimensional (2D) architectures has attracted significant attention in the field of self‐assembly for structural diversity and new functionalization. Although numerous 2D polymer nanosheets have been reported, 2D nanosheets with tubular channels have been unexplored. Herein, we describe a new strategy for the fabrication of stimulus‐responsive conjugated polymer 2D nanosheets with hollow cavities. Amphiphilic macrocyclic diacetylenes self‐assembled in an aqueous solution in a columnar manner to afford bilayered 2D nanosheets with intrinsically tubular nanochannels. UV‐induced polymerization resulted in the generation of blue‐colored tubular conjugated polydiacetylene 2D nanosheets. Immobilization of gold nanoparticles, fluorescence labeling with FRET phenomenon and colorimetric DNA sensing were demonstrated with these new 2D nanosheets. In addition, the free NH2 containing polymerized 2D nanosheet was utilized for conductivity behavior and grafting on graphene oxide (GO). [ABSTRACT FROM AUTHOR]

The composite with strong interaction force was prepared based on organic magadiite (OMAG) and polydiacetylene (PDA). Structural analyses indicate that γ-Aminopropyl triethoxysilane (KH550) acts as a bridge, connecting PDA and OMAG by electrostatic interactions and hydrogen bonding. Thus, PDA can be assembled on OMAG orderly, which allows the PDA-KH550-OMAG to have the properties of reversible dynamic structural changes during hot and cold conversion. It stands for reversible thermochromism. To fabricate the film with higher strength and good applicability, we polymerized nanocomposite film in carboxymethylcellulose matrix via simple preparation method. The film change from bluish purple to red when heated from 20 to 80 ℃, and normalized signal can can recover to 1.2 after ten heating cycles. The film persists in different organic solutions stably, expanding the application scope in harsh environments to become better smart sensing materials. Other coupling agents are difficult to achieve the same results, which further illustrates that amino plays an essential role in the reversible conformation of PDA chain. [ABSTRACT FROM AUTHOR]

Poly-ion complex (PIC) integrating non-antibiotic theranostics holds great promise in the combat against drug-resistant bacteria. Photosensitizers with aggregation-induced emission (AIE) characteristic are particularly intriguing theranostic agents, but incorporating them into antibacterial PIC to enable both fluorescence and reactive oxygen species (ROS) generation turn-on deems a great challenge. Here we report the development of a PIC that can dually boost the fluorescence and ROS generation in the presence of pathogen bacteria. The PIC is constructed based on an anionic polydiacetylene poly(deca-4,6-diynedioic acid) (PDDA), which completely degrades in the presence of ROS. A cationic polymer quaternized poly(2-(dimethylamino)ethyl methacrylate) (PQDMA) that can disrupt bacterial membrane is co-loaded together with a highly efficient AIE photosensitizer TPCI in the PIC. PIC is nonfluorescent initially in that PDDA can quench the AIE of TPCI in PIC. When pathogenic bacteria are present, they can disturb the assembly of PIC to release TPCI, the fluorescence of which turns on sensitively to indicate the existence of bacteria. The on-demand irradiation can be subsequently applied to excite TPCI, which generates ROS to degrade PDDA and deform the PIC. As a result, TPCI and PQDMA are completely released to eliminate bacteria through a synergy of turned-on photodynamic therapy (PDT) and membrane disruption. The highly efficient detection and inhibition against both Gram-negative and Gram-positive bacteria have validated this polydiacetylene-based PIC system as an effective non-antibiotic antibacterial theranostic platform as well as a new strategy to enable "turn-on" fluorescence sensing and imaging of AIE fluorophores. [ABSTRACT FROM AUTHOR]

Colorimetric detection of long chain fatty acids by polydiacetylenes (PDAs)-based sensors is quite a challenge, mainly due to their relatively low solubility in aqueous media. In this study, we developed PDA/Zn 2+ /ZnO nanocomposites in various organic solvents for detecting fatty acids. Oleic acid and steric acid were used as representatives of fatty acids with bent and linear structures, respectively. The nanocomposites dispersed in ethanol exhibited blue-to-red color transition upon increasing the concentration of oleic acid. The use of other solvents including 1-butanol, 1-hexanol, 1-octanol, 1,4-dioxane, hexane, octane and toluene affected the sensitivity of nanocomposites. Furthermore, incorporating cetyltrimethylammonium bromide (CTAB) into the structure of the nanocomposites resulted in a systematic increase of sensitivity. The use of organic solvents simplified the method and allowed direct sensing of the fatty acids. Paper-based sensor was fabricated and utilized as a mobile test kit. This class of colorimetric sensors can also distinguish the bent and linear structures of fatty acids. Our study extends the utilization of PDA-based materials as colorimetric sensors of fatty acids in food industries., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Designing surfaces that enable controlled presentation of multivalent ligand clusters (e.g., for rapid screening of biomolecular binding constants or design of artificial extracellular matrices) is a cross-cutting challenge in materials and interfacial chemistry. Existing approaches frequently rely on complex building blocks or scaffolds and are often specific to individual substrate chemistries. Thus, an interlayer chemistry that enabled efficient nanometer-scale patterning on a transferrable layer and subsequent integration with other classes of materials could substantially broaden the scope of surfaces available for sensors and wearable electronics. Recently, we have shown that it is possible to assemble nanometer-resolution chemical patterns on substrates including graphite, use diacetylene polymerization to lock the molecular pattern together, and then covalently transfer the pattern to amorphous materials (e.g., polydimethylsiloxane, PDMS), which would not natively enable high degrees of control over ligand presentation. Here, we develop a low-viscosity PDMS formulation that generates very thin films (<10 μm) with dense cross-linking, enabling high-efficiency surface functionalization with polydiacetylene arrays displaying carbohydrates and other functional groups (up to 10-fold greater than other soft materials we have used previously) on very thin films that can be integrated with other materials (e.g., glass and soft materials) to enable a highly controlled multivalent ligand display. We use swelling and other characterization methods to relate surface functionalization efficiency to the average distance between cross-links in the PDMS, developing design principles that can be used to create even thinner transfer layers. In the context of this work, we apply this approach using precision glycopolymers presenting structured arrays of N -acetyl glucosamine ligands for lectin binding assays. More broadly, this interlayer approach lays groundwork for designing surface layers for the presentation of ligand clusters on soft materials for applications including wearable electronics and artificial extracellular matrix.

Sprayable stimuli-responsive material coatings represent a new class of detection system which can be quickly implemented to transform a surface into a color-responsive sensor. In this work, we describe a dipicolylamine-terminated diacetylene-containing amphiphile formulation for spray coating on to a simple paper substrate to yield disposable test strips that can be used to detect the presence of lead ions in solution. We find the response to be very selective to only lead ions and that the sensitivity can be modulated by altering the UV curing time after spraying. Sensitive detection to at least 0.1 mM revealed a clear color change from a blue to red phase. This represents the first demonstration of a spray-on sensor system capable of detection of lead ions in solution.

Comprehensive Summary: Wearable devices are a mainstream for our future daily life, where responsive polymer composite fibers represent one of the key components. However, their practical applications are hampered by several challenges, including poor responsive reversibility, poor controllability and low stability as well as single function. Herein, we share our recent studies on overcoming the above challenges for achieving novel responsive polymer composite fibers, especially focusing on chromatic fibers, deformational fibers and their integrations. Furthermore, we introduce a type of novel materials for these responsive fiber materials, i.e., aligned carbon nanotube sheets and fibers simultaneously with excellent electrical, optical and mechanical properties. For the future development, we further highlight the possible directions in this field. What is the most favorite and original chemistry developed in your research group? The conception and realization of display textile. Displays are the basic building blocks of electronics. Integrating displays into textiles offers exciting opportunities for smart electronic textiles, which are believed to change the future life of the human being. For instance, display textiles serve to bridge human‐machine interactions, and a real‐time communication tool may become true for individuals with voice or speech disorders. After hard work for over ten years, we have finally achieved this goal at lab and further produced such display textiles at large scale at industry. How do you get into this specific field? Could you please share some experiences with our readers? When I started to do research independently at Fudan University, I tried to do something unique. I just did not hope to simply follow the available direction. I majored at chemical fibers during my undergraduate study and later made research on electronic devices, so it was natural for me to combine fibers and electronics together. I do not remember the detail time I figured out the idea. In my mind, it should be very interesting and must be very cool. I did not know and even had not thought whether they were useful or not. After the paper was published in 2021, so many people contacted us for the use of display textiles for a spectrum of applications. During the study on the display textiles that have been also investigated for smart systems, we started to explore new smart fiber materials almost at the same time. These smart fiber materials are discussed in this article. How do you supervise your students? First, it is important for me to understand them as every student is unique. Second, according to their characteristics, I may choose specific research projects, often following their interests. Third, I fully respect them when they start the research. They are totally free to decide the work time and work style. I trace the process mainly aiming at solving problems for them. Of course, I keep asking them to enhance their scientific tastes and make the first‐class research, not only so‐called original science or technology. I will try my best to help them to publish their results at top journals, which is important for their future development. During the whole training process, the most important thing I hope to achieve is enjoying science, at least feel successful. It is obviously not easy. Sometimes we make it, and sometimes we fail. We always work for the better full of hope. I sincerely hope that every student, after graduation, will have a good memory at my lab. What is the most important personality for scientific research? I think there are two very important characteristics. One is brave. A scientist should be brave to solve the most difficult problem in the field. The other is imagination. Science is pretty similar to arts in many aspects. We may fix the gap sometimes through imagination. However, it is particularly challenging to train scientists for good imagination in science. [ABSTRACT FROM AUTHOR]

Amphiphilic sugar-functionalised diacetylene lipids undergo facile self-organisation in the solid state, enabling a photo-initiated polymerisation, leading to the formation of sugar-coated polydiacetylenes. The presence of hydrophilic sugar moiety and the long aliphatic chains promote amphiphilicity-driven mesomorphism in these polymers. Maintaining the lyophilic segment uniform, glycolipids that vary in their sugar constitution are prepared, in order to assess mesomorphic changes with respect to varying sugar segment. Mono- and disaccharides are chosen that allow further to identify the changes in the emerging mesomorphic property with the sugar configurations. Whereas a smectic layering is observed common in these glycolipid polymers, the mesophase temperature range and the structural ordering are observed to vary depending on the sugar segment, as adjudged by optical polarising microscopy, calorimetry and X-ray diffraction assessments. Higher clearing temperatures are seen for disaccharide containing glycolipid polymer, as compared to the monosaccharide containing polymer. Further, in conjunction with energy minimised structures, interdigitised lamellar structure is inferred to the polymers. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel attempt: Applying supramolecular polymers to intelligent food packaging. • Multifunctionality: High-strength, gas & UV-barrier, anti-bacterial, and degradable film. • Excellent colorimetric response of the film, accompanied by shrimp spoilage. • Eco-friendly strategy: All materials selected are biodegradable and non-hazardous. The development of sustainable and functional packaging materials has become a very promising way to reduce pollution from traditional plastics. To address the shortcomings of natural materials with single function, poor antimicrobial and mechanical properties, and to develop more competitive green food packaging, a sodium carboxymethyl cellulose based multifunctional packaging film interspersed with wheat straw cellulose fibers (CF) and cellulose nanofibers (CNF) was proposed in this study, where CF and CNF increased the surface area of the film and loading capacity of the functional materials at the micrometer and nanometer levels, respectively. A biodegradable supramolecular polymer, polydiacetylene (PDA), was introduced into the film. Then, ZnO nanoparticles and PDA carboxylate head group coordination self-assembly strategy was utilized to build a PDA/Zn2+ intercalation composite structure, which was able to produce a highly sensitive specific response to biogenic amine and endowed the film with the ability of visual indication, as well as to effectively improve the film's antimicrobial, ultraviolet light shielding, gas barrier, and water resistance properties. Moreover, the dense structure enables the film to withstand more than 50 reciprocal folds of nearly 180°, far exceeding that of ordinary packaging paper (about 10 folds). Composite packaging film enabled effective quality retention and spoilage monitoring of high protein products, especially shrimp with high biogenic amine release. This study provides a valuable reference for the application of supramolecular polymers, such as PDA, in food packaging materials, and gives a diversified development idea for plastic alternative packaging and multifunctional food packaging. [ABSTRACT FROM AUTHOR]

Polydiacetylene (PDA) is a class of color-responsive materials that has been utilized in advanced sensing applications. The development of PDA as an acid sensor often requires structural modification of the headgroup, involving time-consuming synthetic processes. In this study, we have found a versatile route for achieving acid response of PDA materials via a sol-gel method. Simple mixing of sodium hydroxide and a commercial diacetylene monomer, 5,7-hexadecadiynoic acid (HDDA), in an aqueous solution leads to supramolecular assembly to form nanoribbons and consequently gelation under ambient conditions. Interestingly, solid-state sensors of poly-(HDDA-Na+) fabricated from the gels exhibit a colorimetric response to hydrogen chloride (HCl) gas. The red-to-orange color transition takes place at an HCl gas concentration as low as 400 ppm. The response time at 1300 ppm of HCl gas, the lowest lethal concentration causing fatality of a human, is within 1 min. The quick response of the poly-(HDDA-Na+) sensor allows visual detection of HCl gas and provides sufficient time to take safety precautions. This sol-gel process is simple, showing potential for large-scale production. Our study also offers a development path for PDA materials that expands their applications as acid sensors. [ABSTRACT FROM AUTHOR]

The successful topochemical polymerization of bis(selenocyanatomethyl)butadyine 1 is achieved upon association in a 1 : 1 co‐crystal with 1,2‐bis(2‐pyridyl)ethylene (2‐bpen) through strong and linear (NC)−Se⋅⋅⋅NPy chalcogen bonding (ChB) interactions, allowing for an appropriate parallel alignment of the diacetylene moieties toward the solid‐state reaction. Co‐crystal 1⋅(2‐bpen) undergoes polymerization upon heating at 100 °C. The reaction progress was monitored by IR, DSC and PXRD. An enhancement of the polymer conductivity by 8 orders of magnitude is observed upon iodine doping. Strikingly, the course of polymerization is accompanied with sublimation of the ChB acceptor molecules 2‐bpen, providing the polymer in a pure form with full recovery of the co‐former, at variance with the usual hydrogen‐bonded co‐crystal strategies toward polydiacetylenes. [ABSTRACT FROM AUTHOR]

Due to the unique optical and chromatic properties toward various external stimuli, conjugated polydiacetylene (PDA) materials are attracting a great attention from scientists. And the fabrication of PDA embedded composites would further expand the application prospect. In this work, aniline substituted diacetylene derivative was embedded into wax matrix to form a writable composite. After UV induced 1,4‐topochemical polymerization, the patterns generated from the PDA/wax composite showed clearly a blue‐to‐purple‐to‐red colorimetric change upon thermal stimulus. More interestingly, with the introduction of two representative near‐infrared (NIR) dyes to the composite, the PDA also showed blue‐to‐red chromatic transition in response to distinctive NIR lights irradiation. [ABSTRACT FROM AUTHOR]