Monomer Solution Research Articles

Conducting Poly[N-(4-Methoxy Phenyl)Maleamic Acid]/Metals Oxides Nanocomposites for Corrosion Protection and Bioactivity Applications

Corrosion is considered as the most common cause of steel material property degradation, while coatings are effective and popular corrosion protection methods. Coatings come in a variety of forms, each with its own set of effectiveness, methods and constituents. This study used an electrochemical oxidation approach to make Poly [N-(4-Methoxy Phenyl) maleamic acid] from monomer [N-(4-Methoxy Phenyl) maleamic acid] (NPM) in a 3.5% seawater solution. On a low carbon steel [L.C.S] electrode (working electrode), a polymer film was produced. The polymer was created, according to infrared, SEM and FTIR examinations. Using the electrochemical polarization approach, the anticorrosion function of polymer films on L.C.S was examined. Also, adding nanoparticles (NP), like CuO and ZnO to the monomer solution improved the polymers anticorrosion. The results revealed that there was an increase in the L.C.S corrosion rate with the increase of temperature from 293K to 323K, while the values related to coatings polymer inhibition efficiency improved with NPs addition. For the corrosion of L.C.S in salt medium prior to and following polymeric coating, thermodynamic and kinetic activation parameters were estimated. The impact of preparing polymers on certain bacteria strains was also investigated.

Photo-modulation of supramolecular polymorphism in the self-assembly of a scissor-shaped azobenzene dyad into nanotoroids and fibers.

Recent advances in the research field of supramolecularly engineered dye aggregates have enabled the design of simple one-dimensional stacks such as fibers and of closed structures such as nanotoroids (nanorings). More complex and advanced supramolecular systems could potentially be designed using a molecule that is able to provide either of these distinct nanostructures under different conditions. In this study, we introduced bulky but strongly aggregating cholesterol units to a scissor-shaped azobenzene dyad framework, which affords either nanotoroids, nanotubes, or 1D fibers, depending on the substituents. This new dyad with two trans-azobenzene arms shows supramolecular polymorphism in its temperature-controlled self-assembly, leading to not only oligomeric nanotoroids as kinetic products, but also to one-dimensional fibers as thermodynamic products. This supramolecular polymorphism can also be achieved via photo-triggered self-assembly, i.e., irradiation of a monomeric solution of the dyad with two cis-azobenzene arms using strong visible light leads to the preferential formation of nanotoroids, whereas irradiation with weak visible light leads to the predominant formation of 1D fibers. This is the first example of a successful light-induced modulation of supramolecular polymorphism to produce distinctly nanostructured aggregates under isothermal conditions.

Fast Customization of Microneedle Arrays by Static Optical Projection Lithography.

Customized microneedle arrays (CMNAs) hold great promise for precise transdermal delivery in a minimally invasive manner. Currently, the fast customization of microneedle arrays remains a great challenge. Here, we show a static optical projection lithography (SOPL) technology for fast 3D printing CMNAs. In this technology, the digital light is statically projected to induce the spatial polymerization of monomer solutions, and therefore microneedle formation can be precisely controlled by the intensity distribution of the projected light. The obtained CMNAs do not have the stair-like surface and layer-by-layer structure that are associated with the common 3D-printing technologies. This method enables fast fabrication of CMNAs with designed shape, size, and distribution in seconds without mechanical motion system. Up-conversion nanoparticles (UCNPs) were delivered into skin by the CMNAs, to form a personalized dot matrix for in vivo information storage. Under the irradiation of near-infrared (NIR) light, the UCNPs in skin displayed a visible dot matrix, presenting information encoded in the structure of CMNAs. This work demonstrates a SOPL technology for rapidly customizing high-quality microneedle arrays and a CMNA-mediated in vivo information storage strategy.

Patterning Silver Nanowires by Inducing Transient Concentration Gradients in Reaction Mixtures.

Patterning nanocrystals in polymer films is essential for the widespread use of nanocrystals in various fields from optics to electronics; therefore, the development of patterning methods for nanocrystals is an important task. Here, we report a unique approach for patterning silver nanowires (AgNWs) using a thermodynamic driving force induced by transient concentration gradients in reaction mixtures. The procedure starts with the preparation of a photocurable monomer solution containing homogeneously dispersed AgNWs. Ultraviolet illumination through a straight-line mask reduces the polymerization rate of monomers in the masked area, decreasing the polymer concentration in comparison with that in the unmasked area. Such transient polymer concentration gradients yield imbalances in the chemical potentials of AgNWs, inducing the migration of AgNWs to form a straight-line pattern of AgNWs. The pattern of AgNWs was visualized via photoluminescence imaging under a laser scanning confocal microscope and compared with the light patterns applied to the mixture. These observations revealed that the magnitude of the AgNW migration is enhanced as the transient concentration gradient increases by thickening the mask to decrease the intensity of light passing through the mask. The structural features of the AgNW pattern were reproduced using numerical simulations based on a set of reaction-diffusion equations, which suggested the key role of the polymerization kinetics characterized by the Trommsdorff-Norrish effect. Moreover, as the AgNW pattern becomes clearer, the electrical resistance along the patterns decreases and more complex patterns can be produced, indicating the potential of the method. Overall, the present patterning method constitutes a simple approach that only requires illumination through a mask to generate the AgNW pattern, which renders it a promising alternative for patterning nanocrystals in polymer films.

Submicron 3D imaging of liquid–vapor interfaces formed in the Cassie–Baxter state

In this work, we present a method to microscopically investigate the liquid–vapor interfaces on the bottom side of droplets, which were placed on superhydrophobic structures, so that wetting in the Cassie–Baxter (CB) state occurred. These interfaces are hard to access optically, especially when an opaque substrate material is used, which is usually the case for technical applications. In that case, the menisci have to be observed through the droplet, which substantially deteriorates the imaging quality. Other methods that circumvent these distortions, such as optical coherence tomography, are restricted to a resolution of several micrometers. Confocal or fluorescence microscopy additionally requires a transparent substrate. To measure the liquid–vapor interfaces formed in the Cassie–Baxter state with high accuracy liquid droplets of a monomer solution that chemically reacts to form the elastomer, polydimethylsiloxane was placed on structured surfaces. Because double reentrant structures were used, wetting occurred in the Cassie–Baxter state despite the low surface tension of the monomer solution. After curing, it was possible to remove the solid droplets from the surface and investigate them using confocal microscopy, which provides an excellent height resolution of 10 nm. Test structures such as arrays of stripes and holes with variable spacing or diameter were used to investigate the impact of their geometry on the liquid–vapor interfaces formed in the CB state. Although the maximum height of the menisci on the droplet's bottom side is in the region of several 10 μm, the 10 nm resolution is required to adequately compare their topography with simplified theoretical models.

Improving the mechanical performance of P(N‐hydroxymethyl acrylamide/acrylic acid/2‐acrylamido‐2‐methylpropanesulfonic acid) hydrogel via hydrophobic modified nanosilica

AbstractHydrogels with high mechanical strength are essential for its most industrial applications. In this work, the hydrophobic SiO2nanoparticles (M‐SiO2NPs) modified with octadecyltrimethoxysilane were used as physical crosslinker to toughen the mechanical properties of hydrogels. The solution of monomers containing M‐SiO2NPs, N‐hydroxymethyl acrylamide (NHAM), acrylic acid (AA), 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS), was polymerized to prepare a P(NHAM/AA/AMPS)‐based composite hydrogel without any chemical cross‐linker. The composition and microstructure of the hydrogel were carefully studied with Fourier transform infrared spectroscopy and scanning electron microscopy. The mechanical properties of the hydrogel were investigated through compressive and tensile tests. Dynamic swelling tests were carried out at different pH values (1.0–12.0) and salinity (2000–20,000 mg/L) to study the acid resistance, alkali resistance, and salt resistance of the hydrogel. The obtained results showed that the hydrogel exhibited excellent mechanical performance, which was attributed to the unique 3D network formed by the hydrogen bond between M‐SiO2NPs and polymer as well as the hydrophobic association effect between the hydrophobic chains of M‐SiO2NPs. Furthermore, the hydrophobic association effect was enhanced when contacting with salt, acid, and alkali solutions, thus endowing the hydrogel with intensified salt resistance and wider acid–base adaptability range.

One-Pot Preparation of Metal-Polymer Nanocomposites in Irradiated Aqueous Solutions of 1-Vinyl-1,2,4-triazole and Silver Ions.

Metal–polymer nanocomposite polyvinyltriazole–silver nanoparticles were obtained using one-pot synthesis in irradiated aqueous solutions of 1-vinyl-1,2,4-triazole (VT) and silver ions. Gel permeation chromatography data show that upon radiation initiation, the molecular weight of poly(1-vinyl-1,2,4-triazole) increases with increasing monomer concentration. To study the kinetics of polymerization and the features of the radiation–chemical formation of nanoparticles, UV-Vis spectroscopy was used. TEM images show a relatively small average size of the forming nanoparticles (2–3 nm) and a narrow size distribution, which shows the effective stabilization of nanoparticles by triazole substituents at a molar ratio of VT and silver ions of 25/1. The addition of ethyl alcohol was used to increase the efficiency of synthesis and suppress the crosslinking of macromolecules in solution. The results of the work show that aqueous–alcoholic solutions of 1 wt.% VT can be used to obtain soluble nanocomposite materials. 10 wt.% monomer solutions have prospects for use in the preparation of polymer gels filled with nanoparticles.

Solubility of Aβ40 peptide

In this work we measured, by using a direct approach, the equilibrium solubility of recombinant Aβ40 peptide to be S ​= ​0.36 ​± ​0.15 ​μM in aqueous solution of 20 ​mM sodium phosphate buffer at pH 7.4. Microfluidic diffusional sizing (MDS) and mass spectrometry (MALDI-TOF/TOF) with isotope standard were used to quantify the concentration of soluble Aβ40 species coexisting with formed fibrils. A sample set of Aβ40 at different concentrations was incubated at 37 ​°C under quiescent conditions and for different incubation times. After incubation, the samples were centrifuged and the concentration of Aβ40 in the supernatant was determined. This allowed us to also determine the metastable zone in supersaturated Aβ40 monomer solutions, as a function of the observation time, as well as the monomer concentration coexisting with formed fibrils. Moreover, the hydrodynamic radius ( R H ) of the Aβ40 species detected in the supernatant at different time points was also measured, and showed a constant value of ∼1.8 ​nm, consistent with random coil Aβ40 monomers.

High separation performance thin film composite and thin film nanocomposite hollow fiber membranes via interfacial polymerization for organic solvent nanofiltration

Hollow fiber (HF) organic solvent nanofiltration (OSN) membrane has unique self-supporting structure and larger specific surface area over flat OSN membranes, which is much more beneficial for separation processes intensification in chemical related industries. The key of this technology is HF OSN membrane. However, the research works on HF OSN membranes was relatively less till now. In this work, an outer-skinned polyimide HF substrate membrane was spun, and then thin film composite (TFC) membrane was prepared via interfacial polymerization (IP) between ultra-low concentration m-phenylenediamine (MPD) in the aqueous phase and trimesoyl chloride (TMC) in the organic phase on the HF substrate surface, with sodium dodecyl sulfate (SDS) as aqueous additives and triethylamine (TEA) as aqueous catalyst, and subsequently accompanied by crosslinking and solvent activation procedures. Further, thin film nanocomposite (TFN) HF OSN membrane incorporated with graphene oxide (GO) was also prepared. The combination of lower MPD concentration with SDS and TEA as additives in the aqueous monomer solution promote the formation of a TFC HF OSN membrane with average roughness of less than 3 nm, and a rhodamine B (RDB) rejection close to 100%, together with an ethanol permeance higher than 12 L m−2 h−1 MPa−1 under the optimum fabrication conditions. The optimal TFN membrane at a doping GO content of 5.0 mg L−1 achieves up to 20 L m−2 h−1 MPa−1 for the ethanol permeance without sacrificing the RDB rejection (nearly 100%). Moreover, both HF OSN membranes possess good swelling resistance, which proves their application potential in organic solvent system.

Luminescent hydrogels with tunable emission colors and excellent adhesion performance fabricated by lanthanide complexes induced crosslinking and physical interaction

Hydrogels with tunable and responsive luminescence have attracted considerable attention because of their excellent biocompatibility and optical properties. However, most of luminescence hydrogels do not exhibit sufficient adhesion, limiting their further application. Herein, we report the construction of a lanthanide-based luminescent hydrogel with excellent adhesion performance via lanthanide complexes induced crosslinking and physical interaction. Especially, the lanthanide complexes not only can be uniformly dispersed in the monomer solution, but also can be acted as both the coordination crosslinking agent and luminophores. Moreover, upon the addition of lanthanide complexes into the polyacrylamide polymer network containing quaternary ammonium group, the adhesive strength as well as the mechanical behavior of the hydrogel are significantly improved. This work develops a simple strategy for the construction of luminescent hydrogels with adhesion performance and pushes forward their potential application in chemical and biomedical fields.

Fabrication of a Hydrophilic Low-Friction Poly(hydroxyethyl methacrylate) Coating on Silicon Rubber.

Silicon rubber has been widely used in the biomedical field due to its excellent mechanical properties and physiological inertia. However, the hydrophobic properties of silicon rubber surfaces limit their further application. Therefore, constructing a silicon rubber coating with hydrophilic and low-friction surface properties would be highly significant. Existing methods to achieve such coatings, including grafting polymer brushes and the deposition of hydrophilic materials, suffer from several deficiencies such as complicated coating processes and insufficient coating firmness. In this paper, we report a hydrophilic polymer poly(hydroxyethyl methacrylate) (PHEMA) coating that can easily coat the surface of silicon rubber to provide low-friction performance. Sample silicon rubber was treated with benzophenone and hydroxyethyl methacrylate monomer solution in turn. The as-prepared coating was characterized by infrared spectroscopy, X-ray photoelectron spectroscopy, white light interference, and MFT-5000 wear test. The results indicated that the PHEMA coating had excellent hydrophilic properties (with a low contact angle of 9.39°) compared to uncoated silicon rubber. As the concentration of glycerol in the monomer solution was increased, the thickness and surface roughness of the as-prepared coating gradually decreased. The coating was firmly adsorbed on the substrate, and it had a zero-class bonding strength. In addition, the as-prepared coating demonstrated good friction-reduced properties, with the coefficient of friction being reduced by 98.0% compared with the uncoated silicon rubber in simulated blood. In summary, a hydrophilic and low-friction coating was successfully prepared using a simple method, and the results reported herein provide valuable insight into the surface design of similar soft materials.

One-pot electrosynthesis of ultrathin overoxidized poly(3,4-ethylenedioxythiophene) films

In an aqueous electrolyte under an anodic polarization, most of the conductive polymers could undergo an overoxidation due to the hydroxyl radicals formed during water oxidation. Regarding poly(3,4-ethylenedioxythiophene) (PEDOT) only a few reports studied its overoxidation. In this paper, we propose a facile and rapid strategy to prepare an ultrathin (15 nm), pinhole-free and non-conductive overoxidized PEDOT film by electropolymerization of EDOT under potentiostatic conditions in the presence of solely weak-acid anions in the monomer solution. The influence of the pH of this solution as well as the applied potential was studied notably by electrochemical impedance spectroscopy. It was pointed out that the PEDOT film is overoxidized when its electrosynthesis is performed in an aqueous monomer solution of pH 10.5, at 1.1 V/SCE, the monomer solution containing only weak-acid ions as anions (phosphates or carbonates). XPS analyses show that some C and S atoms of the film are oxidized leading to a break of the polymer conjugation and therefore to a decrease of its electronic conductivity. Finally, after adding in the monomer phosphate solution of pH 10.5 perchlorate ions that allow to avoid total overoxidation of the film formed at the very beginning of the process, PEDOT nanowires were obtained.

Templateless Electrosynthesis of Nanostructured PEDOT Films

Conducting polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) and polypyrrole (PPy) have been widely used as electrode materials for supercapacitors. PEDOT is a promising electrode material because of its high electrical conductivity, great environmental stability and high cycling stability. Nanostructuration of the polymers can provide better performances of volumetric swelling and shrinking during charge/discharge processes. We have already described the templatefree electrosynthesis of PPy nanostructures [1-3] but to the best of our knowledge, the easy templateless electrosynthesis of nanostructured PEDOT in aqueous solutions has not been reported yet. This work demonstrates a simple one-step templatefree electrosynthesis method of preparing various structured PEDOT films which show good specific capacitance and cycling stability. By varying some experimental parameters, we have obtained various nanostructures: nanofiber networks, nanorods, nanospheres and nanowires of PEDOT (Figure 1, SEM micrographs of various morphologies of PEDOT obtained using a templateless electrochemical route.). These structures were obtained by simply adjusting the applied potential and the composition of the monomer solution i.e. the concentration of weak-acid anions such as HPO4 2- and the concentration of non-acid anions such as ClO4 -. The growth mechanism of the nanostructured PEDOT films will be discussed. At the very beginning of the process, water oxidation takes place which leads to the formation of hydroxyl radicals and to the evolution of O2. Moreover, the nanostructured PEDOT films show high specific capacitance (~100-200 F/g) and cycling stability (capacitance retention is about 90% after 1000 scans). Therefore, the nanostructured electrogenerated PEDOT films could be used for many applications, such as supercapacitors.

A novel conducting polyamic acid/nanocomposite coating for corrosion protection

Corrosion are of paramount interests to a researcher due to their important impacts on both people’s safety and economy. A recent strategy bases on a new material has been utilized for mitigating corrosions. Conducting polymer-based Nano composites are classes of material that can be promising for corrosion protection. PAA- Nano composites on mild steel (MS) and Electropolymerization of polyamic acid (PAA) was applied in monomer solutions by the techniques of constant potential. The protection property of coating was investigated in 3.5% solution of NaCl by Tafel polarizations at varied temperature (293 - 323K). The effect of varied Nano materials (ZnO and Graphen (G)) upon the protections performances of the Nano composite coating were compared. The results revealed that PAA/Nano composite and PAA provides the best performances for corrosions protections of the MS by reducing its corrosions current densities in comparison with the blank MS. In addition, this coating is featured by AFM, and FT-IR, SEM method. Also، the effect of increasing temperature presented as thermodynamic and kinetic parameters {Ea, ΔH*, ΔS*, and ΔG*}, were calculated and discussed.

In‐situ polymerization of polyaniline in PDADMAC/PSS complex membranes: Effect of the polyelectrolyte stoichiometry

AbstractThe direct polymerization of a polymer in a polyelectrolyte complex membrane is a quick and simple method to enhance the properties and add functionality to a pre‐formed membrane. Here, polyelectrolyte complex membrane (PECs) of poly (diallyl dimethyl ammonium chloride) (PDADMAC) [P+] and poly (styrene sulfonate) [P−] were modified by the in‐situ polymerization of aniline monomer into polyaniline (PANI). The initial PECs were prepared by the co‐precipitation of polyelectrolytes with various [P+]: [P−] molar ratio and were formed into 100 micron thin membranes by compression molding. The in‐situ polymerization of PANI was achieved by sequential dipping of the PECs in ammonium peroxydisulfate solution to load the oxidant and in the aniline monomer solution to initiate the polymerization. Both the polyelectrolyte stoichiometry and the NaCl concentration used during the formation of the complex were found to have a profound effect on the polymerization reaction. UV–visible spectroscopy, X‐ray diffraction, and infrared spectroscopy were used to characterize the changes in color of the PANI membranes and to confirm the synthesis of PANI. Scanning electron microscopy revealed the presence of a dense coating of PANI at the surface of the PEC.

Advanced anticorrosive coating prepared from poly [N-(Pyridine-2-yl) maleamic acid]/graphene derivatives nanocomposites

Poly [N-(Pyridine-2-yl) maleamic acid] (PNPM) is made by the electro chemical polymerization of N-(Pyridine-2-yl) maleamic acid (NPM) monomer on low carbon steel {LCS} substrate as anti -corrosion coating. Graphene modification (G) graphene oxide (GO) and utilizing this material in fabricating Nano composite with polymer matrix has been investigated. Scanning electrons microscope {SEM}, Atomic forces microscope {AFM}, Cyclic voltammetry {CV} and Fourier transform infrared technique {FTIR} have been utilized for characterizing the property and the structure of the polymer Nano composite layer and polymer. The behavior of corrosion of coated and uncoated LCS are measured from the Tafel plots utilizing potentiostatic technique in 3.5% NaCl solution as the environment of corrosive at temperature ranging (293–323) K. Nano materials like graphene oxide (GO) and graphene (G) are added to monomer solution for improving the resistance of corrosion of LCS surface so that the result revealed that the value of corrosion protection efficiencies for polymeric coatings rises after adding Nano materials. Besides, the kinetic and thermodynamic parameters were measured for LCS corrosion after and before polymeric coatings in saline water.

Influence of UV-irradiation intensity and exposure duration on the hemobiocompatibility enhancement of a novel synthesized phosphobetaine zwitterions polyethersulfone clinical hemodialysis membranes.

To improve the biocompatibility of polyethersulfone (PES) membranes utilized for biomedical hemodialysis (HD) applications, surface grafting with hydrophilic polymers has become a reliable modification strategy. Like most photochemical catalyzed reactions, UV-assisted grafting is distinctly advantageous for inducing permanent surface chemistry, enhancing hydrophilicity, improving morphology, and surface charge of membranes. PES membranes may be hydrophilic and chemically stable; however, they also have low protein-binding capacity and very susceptible to fouling and target analyte binding. In this study, novel zwitterionic polymers (PVP-ZW) have been synthesized by UV-assisted grafting PVP to a phosphobetaine monomer in a reaction involving dimethylamino and dioxaphospholane-2-oxide terminal groups in an NVP monomer solution at varying UV exposure conditions. The highlight of the present study is the investigation of the hemocompatibility of coated PES HD membranes at varying UV exposure conditions with respect to membrane chemistry and morphology and its influence on human serum protein adsorption. A clinical investigation of inflammatory biomarker release from incubated coated membranes within uremic blood samples of HD patients reveals they are weak complement and coagulation activators compared to bare PES membrane. The trend of fibrinogen adsorption on coated PES membranes was observed to increase with reducing UV intensity and exposure duration. Fibrinogen adhesion only increased with roughened membrane surfaces, and this also led to the formation of biological activation pathways hindering biocompatibility. Resistance against fibrinogen absorption on zwitterionic modified PES membrane could be linked with the creation of electrostatically induced neutral zwitterionic PVP-phosphobetaine hydration layer with hydrophilic character. Experimental results are accompanied by spectroscopic and morphological imaging evidence. Zwitterion coated PES membranes (PES-PVP-ZW) fabricated from higher UV intensities through longer exposure durations showed significant presence of surface deformations in the forms of inherent exfoliations due to harsh UV reaction conditions. The zeta potential and surface roughness of coated membranes also played significant role in the fibrinogen adsorption on PES membranes during ultrafiltration.

Identical Water Dynamics in Acrylamide Hydrogels, Polymers, and Monomers in Solution: Ultrafast IR Spectroscopy and Molecular Dynamics Simulations.

The dynamics and structure of water in polyacrylamide hydrogels (PAAm-HG), polyacrylamide, and acrylamide solutions are investigated using ultrafast infrared experiments on the OD stretch of dilute HOD/H2O and molecular dynamics simulations. The amide moiety of the monomer/polymers interacts strongly with water through hydrogen bonding (H-bonding). The FT-IR spectra of the three systems indicate that the range of H-bond strengths is relatively unchanged from bulk water. Vibrational population relaxation measurements show that the amide/water H-bonds are somewhat weaker but fall within the range of water/water H-bond strengths. A previous study of water dynamics in PAAm-HG suggested that the slowing observed was due to increasing confinement with concentration. Here, for the same concentrations of the amide moiety, the experimental results demonstrate that the reorientational dynamics (infrared pump-probe experiments) and structural dynamics (two-dimensional infrared spectroscopy) are identical in the three acrylamide systems studied. Molecular dynamics simulations of the water orientational relaxation in aqueous solutions of the acrylamide monomer, trimer, and pentamer are in good agreement with the experimental results and are essentially chain length independent. The simulations show that there is a slower, low-amplitude (<7%) decay component not accessible by the experiments. The simulations examine the dynamics and structure of water H-bonded to acrylamide, in the first solvent shell, and beyond for acrylamide monomers and short chains. The experiments and simulations show that the slowing of water dynamics in PAAm-HG is not caused by confinement in the polymer network but rather by interactions with individual acrylamide moieties.

Tiny yet tough: Maximizing the toughness of fiber-reinforced soft composites in the absence of a fiber-fracture mechanism

Tiny yet tough: Maximizing the toughness of fiber-reinforced soft composites in the absence of a fiber-fracture mechanism

Thermal Induced Polymerization of l‐Lysine forms Branched Particles with Blue Fluorescence

AbstractThe polycondensation of amino acids can originate complex polymers that display fascinating structural and optical properties. Thermally induced amidation of l‐lysine allows forming a branched polymer without the support of any catalyst. The polycondensation is completed at 240–250 °C; at higher temperatures, the amino acid degrades. The obtained polylysine particles have been studied by transmission electron microscopy (TEM), nuclear magnetic resonance, and infrared spectroscopy that allow for investigating the different steps of the synthesis. The resulting structure is characterized by peculiar optical properties, e.g., excitation‐dependent blue fluorescence and good quantum efficiency. Hydrogen bonds and the interactions of the amino acids are considered responsible for the optical properties of both l‐lysine monomer solutions at high concentrations and the branched nanopolymers.