Oxidative Polymerization Research Articles

Synthesis and Characterization of PVA/PANI Nanofiber as Active Material for Humidity Sensors

PANI is a nanostructure conductive polymer that has been widely researched by making nanofibers using electrospinning, by adding PVA as a non-conductive material. In this research, we have successfully synthesized PVA/PANI nanofiber using the electrospinning method and applied it as a humidity sensor. The oxidation polymerization method was conducted to produce polyaniline (PANI) powder. PVA was used as a non-conductive polymer to carry PANI. PANI is blended with 10 % PVA to produce nanofiber PVA/PANI. The results of the synthesis of PVA/PANI nanofibers using the electrospinning method have been characterized by FTIR and EDX to identify the functional groups and elements of PVA/PANI. The FTIR results confirmed that for the PVA nanofiber samples, the type of polyvinyl alcohol bond has been identified according to the reference. The EDX results show the elements C, O and N. The element nitrogen (N) is the characteristic element of polyaniline (C6H5(NH)2)n. The optical Microscope and Scanning Electron Microscope show that the electrospinning method has succeeded in synthesizing PVA/PANI nanofibers with a fiber size of around 0.313 mm. The porosity of PVA/PANI is around 55 %, which is related to the ability of PVA/PANI sensitivity to detect humidity. These results are demonstrated by measurements using a Four-Point Probe (FPP), with the humidity value varying from 64 - 80 %. The results show that variations of PANI powder content improve the sensitivity performance of PVA/PANI nanofibers. This method can optimize PVA/PANI nanofiber as a humidity sensor, increase conductivity flexibility, make it easier and enhance the PANI to use as an active sensor. HIGHLIGHTS The active material for the sensor is polyaniline-based. Polyaniline oxidation polymerization using a method with solid acid doping, which can increase the conductivity of polyaniline (PANI). The formation of PANI nanofibers increases the sensing activities’ effectiveness. Polyvinyl alcohol (PVA) is used as a carrier to facilitate the synthesis process by electrospinning. GRAPHICAL ABSTRACT

Melanin-Ce6-loaded polydopamine nanoparticles-based enhanced phototherapy for B16 melanoma cancer cells

Melanoma is one of the most aggressive and lethal types of cancer owing to its metastatic propensity and chemoresistance property. An alternative therapeutic option is photodynamic and photothermal therapies (PDT/PTT), which employ near-infrared (NIR) light to generate heat and reactive oxygen species (ROS). As per previous reports, Melanin (Mel), and its synthetic analogs (i.e. polydopamine nanoparticles) can induce NIR light-mediated heat energy, thereby selectively targeting and ameliorating cancer cells. Similarly, chlorin e6 (Ce6) also has high ROS generation ability and antitumor activity against various types of cancer. Based on this tenet, In the current study, we have encapsulated Mel-Ce6 in a polydopamine (PDA) nanocarrier (MCP NPs) synthesized by the oxidation polymerization method. The hydrodynamic diameter of the synthesized spherical MCP NPs was 139 ± 10 nm. The MCP NPs, upon irradiation with NIR 690 nm laser for 6 min, showed photothermal efficacy of more than 50 °C. Moreover, the red fluorescence in the MCP NPs due to Ce6 can be leveraged for diagnostic purposes. Further, the MCP NPs exhibited considerable biocompatibility with the L929 cell line and exerted nearly 70% ROS-mediated cytotoxicity on the B16 melanoma cell line after the laser irradiation. Thus, the prepared MCP NPs could be a promising theranostic agent for treating the B16 melanoma cancer.

Surface hydration of trimethylamine N–oxide/perovskites hybrid aerogel facilitates anti–fouling solar desalination and seawater electrocatalysis

Developing active and stable electrocatalysts for oxygen evolution reaction is of great significance to generate oxygen and hydrogen by seawater electrolysis, which however remains some issues that high energy consumption and chloride corrosion. Here we pioneered a polymer/inorganic hybrid engineering strategy for achieving excellent salt resistance solar evaporation and oxygen evolution performance (OER). The La0.9Sr0.1CoO3/nickel foam–cellulosic aerogel (LSC1/NF–CA) was synthesized by engineering Trimethylamine N–oxide (TMAO) polymer brush onto the surface of hybrid aerogels composed of La0.9Sr0.1CoO3/Ni foam (LSC1/NF) and cellulose/polyvinyl alcohol, which has good hydrophilic features, intrinsic solar capture capacity, and stable OER performance in seawater. Benefiting from the synergy of solar desalination with surface hydration effect of TMAO, the LSC1/NF–CA presents a superior catalytic activity, requiring a lower overpotential of 341 mV and a tafel slope of 58.2 mV dec−1 at 10 mA cm−2 under 6.0 sun illumination. Our results establish a new strategy that can guide the design of stable and efficient polymer/inorganic hybrid catalysts, which shows a promising prospect as alternatives to noble metal–based catalysts for seawater splitting.

Synthesis and Oxidative Degradation of Leucine-Based Poly(diacylhydrazine).

Diacylhydrazine is thermally and chemically stable, and it remains inert to oxygen even at high temperatures. However, it is rapidly oxidized by sodium hypochlorite, leading to its decomposition into carboxylic acid and nitrogen gas. In the synthesis of a novel poly(diacylhydrazine) as an oxidatively degradable polymer, L-leucine methyl ester is acylated by terephthaloyl chloride. Subsequent hydrazination yields a bishydrazide monomer. The oxidative coupling polymerization of this monomer produces poly(diacylhydrazine). The molecular structures of the products are confirmed by an 1H NMR analysis. A polymodal molecular weight distribution and a large polydispersity index are observed by GPC in all cases. A 10% weight loss temperature is noted at 286 °C in air by TGA. The obtained polymer is not oxidized by oxygen. No glass transition is observed below the decomposition temperature. Upon the treatment of the poly(diacylhydrazine) with sodium hypochlorite solution, decomposition occurs rapidly, resulting in monomeric carboxylic acid and nitrogen gas. The L-leucine-based poly(diacylhydrazine) serves as a novel on-demand degradable polymer with high levels of thermal and chemical stability during usage.

Designing hard carbon microsphere structure via halogenation amination and oxidative polymerization reactions for sodium ion insertion mechanism investigation

Hard carbon as a negative electrode material for sodium-ion batteries (SIBs) has great commercial potential and has been widely studied. The sodium-ion intercalation in graphite domains and the filling of closed pores in the low voltage platform region still remain a subject of controversy. We have successfully constructed hard carbon materials with a pseudo-graphitic structure by using polymerizable p-phenylenediamine and dichloromethane as carbon sources. This was achieved by a halogenated amination reaction and oxidative polymerization. It was found that the capacity of hard carbon materials mainly originates from intercalation into graphite domains. The study found that the prepared hard carbon could store 339.33 mAh g−1 of sodium in a reversible way at a current density of 25 mA g−1, and it had an initial coulomb efficiency of 80.23%. It even maintained a reversible sodium storage capacity of 125.53 mAh g−1 at a high current density of 12.8 A g−1. Based on the analysis of hard carbon structure and electrochemical performance, it was shown that the materials conform with an “adsorption-intercalation” mechanism for sodium storage.

Polyaniline-supported g-C3N4/ZnO/Ag2CrO4 composite for photodegradation of methylene blue under visible light irradiation

Organic dyes are a major source of environmental pollution from different industries. To remove these recalcitrant, a novel ternary g-C3N4/ZnO/Ag2CrO4 and its polyaniline-supported (PANI) composites were synthesized using an “in situ” oxidative polymerization approach. XRD, SEM, UV–Vis DRS, and PL techniques were utilized to characterize the as-prepared composites. The photocatalytic efficiency was evaluated using a model organic pollutant, methylene blue (MB), and samples of the effluent of the textile industry. The as-synthesized ternary g-C3N4/ZnO/Ag2CrO4 (ZT3= 87.87 %) composite showed better photocatalytic performance than the single (5 %) and binaries (15–25 %) counterparts for MB degradation. The influence of various experimental settings on the photodegradation of MB dye was examined and these were an initial dye amount of 10 ppm, photocatalyst load of 0.15 g/L, and pH 10. Under optimized conditions, PANI-supported g-C3N4/ZnO/Ag2CrO4 composite (PAST) demonstrated substantial degradation efficiency (97.5 %). The reusability study of the spent catalyst revealed a reduced efficiency from 97.5 to 78.5 % photodegradation of MB after four successive cycles, demonstrating the photocatalyst's stability and efficiency. According to the study on the effect of scavengers, h+ plays a significant part in the discoloration of MB. The PAST photocatalyst outperformed the MB discoloration (97.5 %) and adequate degradation for real textile effluent samples (77.7 %) collected from Hawassa textile industries. The photodegradation efficiency result of this study demonstrated that PANI-supported g-C3N4/ZnO/Ag2CrO4 might serve as an advantageous photocatalyst for the efficient removal of MB and other dyes under visible light irradiation at the optimum conditions. The total estimated cost analysis of synthesis and photocatalytic degradation using Polyaniline-supported g-C3N4/ZnO/Ag2CrO4 composite found that it was quite affordable, costing around $5 per 1,000 L of wastewater treatment.

Functional carbon nanoparticles modified poly(3,4-ethylenedioxythiophene) nanocomposites with enhanced dielectric and antibacterial properties

The importance of nanocomposites with tailored properties is growing due to their applications in various fields. In the present study, poly(3,4-ethylenedioxythiophene) (PEDOT) and functionalized carbon nanoparticles (f-CNPs) are synthesized by in-situ chemical oxidative polymerization and pyrolysis methods, respectively. The f-CNPs-PEDOT nanocomposites are prepared by varying the concentration of PEDOT (i.e., 1, 2.5, 5, 10, and 20 wt%), and the thermal stability, dielectric properties and antibacterial activities of f-CNPs-PEDOT nanocomposites were evaluated. The dielectric studies indicated that the addition of PEDOT has enhanced the dielectric properties due to interfacial polarization effect, whereas decreased the thermal stability due to degradation of PEDOT in the nanocomposite, however, it is higher than the pure PEDOT. The antimicrobial potential of synthesized f-CNPs-PEDOT nanocomposites was studied against two different bacterial strains, namely Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The findings of this research have potential to open new opportunities for employing f-CNPs-PEDOT nanocomposites in physical sciences and antimicrobial applications.

Quaternary Ammonium Assisted Synthesis of Melanin-like Poly(l-DOPA) Nanoparticles with a Boosted Photothermal Effect.

Poly(levodopa) nanoparticles (P(l-DOPA) NPs) are another kind of melanin mimetic besides well-established polydopamine nanoparticles (PDA NPs). Due to the presence of carboxyl groups, the oxidative polymerization of l-DOPA to obtain particles was not as efficient as that of dopamine. Several established methods toward P(l-DOPA) NP fabrication do not combine convenience, morphological regularity, size controllability, low cost, and adaptability to metal-free application scenarios. In this work, P(l-DOPA) NPs were successfully prepared in hot water with the assistant of organic quaternary ammonium, due to the extra physical cross-linking mediated by cations. The employed physical interactions could also be affected by quaternary ammonium structure (i.e., number of cation heads, length of alkyl chain) to achieve different polymerization acceleration effects. The obtained P(l-DOPA) NPs retained superior photothermal properties and outperformed PDA-based melanin materials. Furthermore, P(l-DOPA) NPs were used in photothermal tumor therapy and showed better efficacy. This study offers new insights into the synthesis of melanin-like materials, as well as new understanding of the interaction between quaternary ammonium and bioinspired polyphenolic materials.

Synthesis of transparent polymer hybrids consisting of gelatin, as a natural polymer, and zinc oxide

Abstract Gelatin and zinc oxide (ZnO) polymer hybrids were prepared via the sol–gel reaction of zinc acetate dihydrate in the presence of gelatin. When the gelatin/ZnO ratio was 9/1, a transparent polymer hybrid was obtained. This hybrid contained no phase separations consisting of organic and inorganic phases. Microscopic or submicroscopic aggregations and separations between gelatin and ZnO were clearly observed in the sample with a high inorganic content. The results of thermal analysis showed that the yield of ceramic decreased as ZnO content increased, and a 10% weight loss temperature increased as gelatin content increased. FT-IR measurements suggested the formation of intermolecular interactions, thought to be hydrogen bonds, between gelatin and ZnO. Furthermore, the results of XRD measurements revealed that the hybrid with a ZnO content of 10% is amorphous.

Synthesis of novel conducting triblock copolymer poly(thiophene-co-pyrrole-co-aniline) by chemical oxidative polymerization method for gas sensor application

The conducting triblock copolymer P(Th-co-Py-co-Ani) of thiophene (Th), pyrrole (Py), and aniline (Ani) has been synthesized by chemical oxidative polymerization method using anhydrous iron (III) chloride (FeCl3) as an oxidizing agent in presence of acetonitrile solvent at 0–8°C. Characterizations of the synthesized copolymer were performed by Attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction analysis (PXRD), UV-Vis spectroscopy, elemental analysis (CHNS), Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM). Notably, UV-Vis spectroscopy revealed that triblock copolymers exhibit highly conjugated conducting polymer backbone, essential for its electrical conductivity and suitability for various applications. The prepared P(Th-co-Py-co-Ani) material was investigated for the gas sensing property of several gases such as ammonia, acetone, carbon monoxide, ethanol and methane. The gas sensing study revealed that P(Th-co-Py-co-Ani) demonstrates promising gas sensing capabilities, particularly at room temperature.

A Review of Weathering Studies in Plastics and Biocomposites-Effects on Mechanical Properties and Emissions of Volatile Organic Compounds (VOCs).

Polymeric materials undergo degradation when exposed to outdoor conditions due to the synergistic effects of sunlight, air, heat, and moisture. The degradation can lead to a decline in mechanical properties, fading, surface cracking, and haziness, attributed to the cleavage of the polymer chains and oxidation reactions. Accelerated weathering testing is a useful technique to evaluate the comparative photodegradation of materials within a reasonable timeframe. This review gives an overview of the different degradation mechanisms occurring in conventional plastics and bio-based materials. Case studies on accelerated weathering and its effect on the mechanical properties of conventional plastics and biocomposites are discussed. Different techniques for analysing volatile organic emissions (VOCs) have been summarized and studies highlighting the characterization of VOCs from aged plastics and biocomposites after aging have been cited.

Preparation of polypyrrole-functionalized recycled cotton fiber as a renewable and eco-friendly cellulose-based adsorbent for water decolorization: Comprehensive batch and fixed-bed column study

Cotton fiber is a low-cost material made from renewable and eco-friendly cellulose and can be used for various applications. However, raw cellulose has a low capacity for capturing pollutants. In this study, recycled cotton fiber was modified with polypyrrole through a chemical oxidative polymerization approach to enhance its implementation and suitability for removing reactive orange 5 (RO5) and reactive yellow 15 (RY15) from aqueous solutions. The cotton/polypyrrole (cotton/ppy) was characterized using SEM, EDS FTIR, and XRD techniques. These analyses indicated that polypyrrole was successfully coated on the cotton fiber. The optimal conditions for maximizing adsorption efficiency, including contact time, concentration of dye, adsorbent dosage, pH levels, and temperature, were determined. RO5 and RY15 eliminations are enhanced in the acidic environment (pH=2, contact time (RO5: 120 min, RY15: 90 min, adsorbent dosage: 200 mg, dye concentration (RO5: 20 mg/L, RY15: 40 mg/L)). The best fit for the adsorption procedure of RO5 and RY15 is the Temkin isotherm model, which indicates a chemisorption process delivers viable mechanism for the adsorption of RO5 (R2 =0.992) and RY15 (R2 = 0.987). Moreover, pseudo-first-order is the leading kinetic model for both RO5 (R2 = 0.999) and RY15 (R2 = 0.995). Furthermore, the study of the fixed-bed column was carried out, showing that the service volume decreased as the flow rate increased. The removal efficiency for RO5 and RY15 exceeded 80% even after using cotton/ppy adsorbent eight times. Therefore, the sustainable polypyrrole-functionalized recycled cotton fiber adsorbent is an excellent choice to eliminate dye effluents.

How Wide and High can Polyhedral Liquid Marbles be Fabricated?

AbstractLiquid marbles (LMs) are liquid droplets in gaseous phase, which are generally millimeter size, coated by solid particles. In this study, how wide and high LMs can be fabricated is investigated. Polyhedral LMs are fabricated using polymer plates with millimeter to meter sizes as a stabilizer and water as an inner liquid. Rectangular LMs with widths exceeding 1 m, the largest width ever reported, can be successfully fabricated. The height of the LMs is found to be subject to restriction by the hydrostatic pressure and cubic LMs with heights of up to 5 mm, which is the maximum height limit for LMs stabilized with nano/micrometer‐sized particles, are fabricated. Reduction of the hydrostatic pressure by changing the LM shape from cube to pyramid and introduction of particle‐stabilized bubble into the LM enabled the increase of height of the LM up to 9.8 mm, the highest height ever reported. Investigation using non‐aqueous liquids as an inner liquid confirmed that the longer the capillary length, the higher the maximum possible height of LMs. Finally, the polyhedral LMs are demonstrated to function as a microreactor for silver mirror reaction and chemical oxidative polymerization, resulting in the formation of Janus polymer plates.

Correction to “Ultrathin Zn-Gallate Catalyst: A Remarkable Performer in CO2 and Propylene Oxide Polymerization”

Correction to “Ultrathin Zn-Gallate Catalyst: A Remarkable Performer in CO₂ and Propylene Oxide Polymerization”

Smart polyurethane endosponges for endoluminal vacuum therapy: Integration of a bacteria sensor

The development of smart biomedical devices as efficient tools in early diagnosis and therapy monitoring has recently witnessed unprecedented growth, becoming an emerging field in biomedical engineering. Sponges for endoluminal vacuum therapy, which are intended for transmitting negative pressure as trigger for tissue regeneration and for draining infections in anastomotic leakages, are massively used implants with very complex geometry and high risk of infection. In this work, commercial polyurethane (PU) sponges have been converted into smart biomedical devices by incorporating an electrochemical sensor to monitor the growth of bacteria. Such innovative approach, which allows to track the tissue healing process avoiding further infection development, has been performed applying a three-step process: 1) activation of PU using low pressure oxygen plasma; 2) incorporation of conducting polymer (CP) nanoparticles (NPs) at the surface of the activated PU by chemical oxidative polymerization; and 3) formation of a homogeneous electroactive coating using the CP NPs obtained in 2), as growth nuclei in an electrochemical polymerization. The functionalized PU sponge is able to monitor the bacteria growth in the surrounding media by detecting the concentration of nicotinamide adenine dinucleotide (NADH) from respiration reactions in the cytosol (i.e. bacteria do not have mitochondria). Conversely, respiration in normal eukaryotic cells takes place in the mitochondria, whose double membrane is not permeable to NADH. The sensing performance of the CP-coated PU sponges (limit of detection: 0.06 mM; sensitivity: 1.21 mA/cm2) has been determined in the lab using NADH solutions, while a proof of concept have been conducted using Escherichia coli bacteria cultures.

Room-temperature NH3-sensor: SnO2@PANI core-shell hollow spheres

A novel room-temperature NH3-sensing material (SnO2@PANI core-shell hollow nanospheres) was synthesized by coating various amounts of PANI on SnO2 hollow nanospheres using a simple in-situ chemical oxidation polymerization method. The morphology and nanostructures of the synthesized sensing materials were characterized using SEM, TEM, FTIR, and XRD. Gas-sensing tests demonstrate that SP-5 exhibits the highest response to NH3 at room temperature, with a response value (26.48 at 500 ppm) more than 6 times higher than that of pure PANI (4.35). This sensor displays excellent selectivity, with good anti-interference capability to CO and NO2. The improved sensing performance of the core-shell hollow structure is attributed to the unique structure and p-n heterojunction between PANI and SnO2, which is confirmed by EIS spectra.

Biocompatible PANI-Encapsulated Chemically Modified Nano-TiO2 Particles for Visible-Light Photocatalytic Applications.

Polyaniline (PANI) constitutes a very propitious conductive polymer utilized in several biomedical, as well as environmental applications, including tissue engineering, catalysis, and photocatalysis, due to its unique properties. In this study, nano-PANI/N-TiO2 and nano-PANI/Ag-TiO2 photocatalytic composites were fabricated via aniline's oxidative polymerization, while the Ag-and N-chemically modified TiO2 nanopowders were synthesized through the sol-gel approach. All produced materials were fully characterized. Through micro-Raman and FT-IR analysis, the co-existence of PANI and chemically modified TiO2 particles was confirmed, while via XRD analysis the composites' average crystallite size was determined as ≈20 nm. The semi-crystal structure of polyaniline exhibits higher photocatalytic efficiency compared to that of other less crystalline forms. The spherical-shaped developed materials are innovative, stable (zeta potential in the range from -26 to -37 mV), and cost-effective, characterized by enhanced photocatalytic efficiency under visible light (energy band gaps ≈ 2 eV), and synthesized with relatively simple methods, with the possibility of recycling and reusing them in potential future applications in industry, in wastewater treatment as well as in biomedicine. Thus, the PANI-encapsulated Ag and N chemically modified TiO2 nanocomposites exhibit high degradation efficiency towards Rhodamine B dye upon visible-light irradiation, presenting simultaneously high biocompatibility in different normal cell lines.

Exploiting Principal Component Analysis (PCA) to reveal temperature, buffer and metal ions' role in neuromelanin (NM) synthesis by dopamine (DA) oxidative polymerization

Neuromelanin (NM) plays a well-established role in neurological disorders pathogenesis; the mechanism of action is still discussed and the investigations in this field are limited by NM's complex and heterogeneous composition, insolubility, and low availability from human brains. An alternative can be offered by synthetic NM obtained from dopamine (DA) oxidative polymerization; however, a deep knowledge of the influence of both physicochemical parameters (T, pH, ionic strength) and other compounds in the reaction media (buffer, metal ions, other catecholamines) on DA oxidation process and, consequently, on synthetic NM features is mandatory to develop reliable NM preparation methodologies. To partially fulfill this aim, the present work focuses on defining the role of temperature, buffer and metal ions on both DA oxidation rate and DA oligomer size. DA oxidation in the specific conditions is monitored by UV–Vis spectroscopy and Principal Component Analysis (PCA) is run either on the raw spectra to model the background absorption increase, related to small DA oligomers formation, or on their first derivative to rationalize DA consumption. After having studied three case studies, 3-Way PCA is applied to directly evaluate the effect of temperature and buffer type on DA oxidation in the presence of different metal ions. Despite the proof-of-concept nature of the work and the number of compounds still to be included in the investigation, the preliminary results and the possibility to further expand the chemometric approach represent an interesting contribution to the field of in vitro simulation of NM synthesis.

A universal method for preparing biomass derived topologically defective carbons with superior catalytic performance in cationic radical polymerization

This study aims to develop a universal preparation method for biomass-derived topologically defective carbons and reveal the catalytic mechanism of such carbons for cationic radical polymerization. Firstly, bamboo fiber-derived topologically defective carbon (BFTC) is prepared by an ammonia-assisted heat treatment method. BFTC can significantly promote the chemical oxidative polymerization of 3-aminophenylboronic acid (a typical cationic radical polymerization process) and obtain high molecular weight products, which is mainly attributed to the rich topological defect structure of BFTC. Secondly, the ammonia-assisted heat treatment method is applied to two other biomasses, and the derived carbons have similar microstructure and chemical composition to BFTC, indicating the universality of this method at the material preparation level; meanwhile, these derived carbons also exhibit excellent catalytic properties when they promote 3-aminophenylboronic acid (ABA) polymerization, which further confirms the universality of this method from the perspective of material properties. Finally, research on the catalytic mechanism shows that there is an interaction based on partial electron transfer between the topological defects of the carbon catalyst and ABA or ABA-derived radical. This effect promotes the rapid derivatization of ABA into cationic radical, and also improves the stability of the radical, thereby achieving efficient polymerization of ABA around the topological defect active center. Therefore, this study confirms the universality of the ammonia-assisted heat treatment method to prepare biomass-derived topologically defective carbon, and such defective carbons are likely to serve as catalysts for cationic radical polymerization.

Light-triggered AND logic tetrapeptide dynamic covalent assembly

We demonstrate light-triggered dynamic covalent assembly of a linear short tetrapeptide containing two terminal cysteine residues in an AND logic manner. A photobase generator is introduced to accomplish light-mediated pH regulation to increase the reduction potential of thiols in the tetrapeptide, which activates its oxidative polymerization through disulfide bonds. Interestingly, it is elucidated that under light irradiation, mere co-existence of photobase generator and the oxidizing agent permits the polymerization performance of this tetrapeptide. Hence, a light-triggered AND logic dynamic covalent assembly of a tetrapeptide is achieved. Further, upon redox response, the reversible aggregation and disaggregation can be transformed for numerous times due to the dynamic covalent feature of disulfide bond. As a comparison, no assembly occurs for a short peptide containing one terminal cysteine residue under the same stimuli condition. This work offers a new approach to remotely control programmable molecular assembly of short linear peptides based on dynamic covalent bond, holding great potential in wide bioapplications.