Fluorescent Polyurethane Research Articles

A Fluorescent Polyurethane with Covalently Cross-Linked Rhodamine Derivatives.

Rhodamine derivatives (RDs) with three reactive hydrogens were synthesized and well characterized by Fourier transform infra-red spectroscopy (FTIR), 1H nuclear magnetic resonance (1H NMR) and electrospray ionization mass spectra (ESI mass). Then, the obtained RD was covalently cross-linked into polyurethane (PU) matrix through chemical linkages to fabricate a network structure, and the fluorescent properties, mechanical properties, thermal stability, and emulsion particle size were systematically investigated. Results demonstrate that PU-RD maintains initial fluorescent properties and emits desirable yellow fluorescence under ultraviolet irradiation. Moreover, compared with linear PU without fluorescers, PU-RD shows clearly improved mechanical properties and thermal stability, on account of the formed network structures.

Reaction-based highly selective and sensitive monomer/polymer probes with Schiff base groups for the detection of Hg2+ and Fe3+ ions.

It is urgent and important to detect heavy metals in environments. In this work, novel reaction-based fluorescent probes were obtained by Schiff base reaction. The probes with Schiff base moiety (-C=N-) undergo irreversible hydrolysis in the presence of Hg2+ and Fe3+. They exhibit perfect high selectivity and sensitivity to Hg2+and Fe3+ ions. Upon the addition of Hg2+and Fe3+, fluorescence intensity of the probes increased notably. And the color of the probe changes from brown to bright green under UV light, which can realize "naked eye" detection. In addition, Schiff base group was introduced into polyurethane chain through condensation polymerization reaction. As expected, the fluorescent polyurethane probe (P2) maintained the detection performance of its original small molecules (BSD). Even more P2 showed a more sensitive detection effect than BSD, and the detection limits of P2 for Hg2+ and Fe3+ reach 0.19μM and 0.21μM, respectively. It indicates that Reaction-based probes could be a useful tool for the detection of Hg2+ and Fe3+.

Cover Feature: Bioinspired Healable Mechanochromic Function from Fluorescent Polyurethane Composite Film (ChemistryOpen 3/2020)

Cover Feature: Bioinspired Healable Mechanochromic Function from Fluorescent Polyurethane Composite Film (ChemistryOpen 3/2020)

Bioinspired Healable Mechanochromic Function from Fluorescent Polyurethane Composite Film.

Camouflage and wound healing are two vital functions for cephalopods to survive from dangerous ocean risks. Inspired by these dual functions, herein, we report a new type of healable mechanochromic (HMC) material. The bifunctional HMC material consists of two tightly bonded layers. One layer is composed of polyvinyl alcohol (PVA) and titanium dioxide (TiO2) for shielding. Another layer contains supramolecular hydrogen bonding polymers and fluorochromes for healing. The as‐synthesized HMC material exhibits a tunable and reversible mechanochromic function due to the strain‐induced surface structure of composite film. The mechanochromic function can be further restored after damage because of the incorporated healable polyurethane. The healing efficiency of the damaged HMC materials can even reach 98 % at 60 °C for 6 h. The bioinspired HMC material is expected to have potential applications in the information encryption and flexible displays.

Synthesis and Morphological Control of Biocompatible Fluorescent/Magnetic Janus Nanoparticles Based on the Self-Assembly of Fluorescent Polyurethane and Fe₃O₄ Nanoparticles.

Functionalized Janus nanoparticles have received increasing interest due to their anisotropic shape and the particular utility in biomedicine areas. In this work, a simple and efficient method was developed to prepare fluorescent/magnetic composite Janus nanoparticles constituted of fluorescent polyurethane and hydrophobic nano Fe3O4. Two kinds of fluorescent polyurethane prepolymers were synthesized by the copolymerization of fluorescent dye monomers, and the fluorescent/magnetic nanoparticles were fabricated in one-pot via the process of mini-emulsification and self-assembly. The nanostructures of the resulting composite nanoparticles, including core/shell and Janus structure, could be controlled by the phase separation in assembly process according to the result of transmission electron microscopy, whereas the amount of the nonpolar segments of polyurethane played an important role in the particle morphology. The prominent magnetic and fluorescent properties of the Janus nanoparticles were also confirmed by vibrating magnetometer and confocal laser scanning microscope. Furthermore, the Janus nanoparticles featured excellent dispersity, storage stability, and cytocompatibility, which might benefit their potential application in biomedical areas.

Toward Enhancing Wearability and Fashion of Wearable Supercapacitor with Modified Polyurethane Artificial Leather Electrolyte

Inspired by the sophisticated artificial leather garment industry and toward enhancing wearability of energy storage devices, we demonstrate a polyurethane artificial leather supercapacitor with large sheet electrodes embedded in the leather layer simultaneously working as a polyelectrolyte. This design totally reserves textiles underneath and thus addresses the well-known challenge of wearing comfortability. It provides a revolutionary configuration of wearable supercapacitors: the artificial leather on garment is also a supercapacitor. Unlike the polyvinyl alcohol-based acidic electrolytes, which are widely used, sodium chloride is used to modify the intrinsically fluorescent polyurethane leather for ionic transportation, which has no harm to human. The fluorescent leather supercapacitor is easily transferrable from any arbitrary substrates to form various patterns, enabling multifunctionalities of practical wearability, fashion, and energy storage.

Synthesis and Characterization of a Fluorescent Water-Borne Polyurethane Based on a Novel Naphthalimide Dye

ABSTRACTA waterborne-polyurethane (WPU) dye, based on the fluorescent dye 4-diamino propane-N-allyl-1,8- naphthalimide (WPU-DAN), was synthesized by attaching 4-diamino propane-N-allyl-1,8- naphthalimide (DAN) onto both ends of the polyurethane (PU) chains according to a prepolymer−ionomer process. The synthetic process was confirmed by Fourier transform infrared spectroscopy (FTIR) and UV-visible absorption. The glass transition temperature, molecular weight and average particle sizes were measured. The glass transition temperatures of WPU and WPU-DAN were 46.6 and 49.8°C, respectively. In addition, the particle size distributions of WPU-DAN and WPU were 140 and 134 nm, respectively. The thermal behaviour of WPU-DAN showed improvement compared to WPU. The fluorescence intensity of WPU-DAN was enhanced more than DAN due to the naphthalimide groups attached to the chains, and the fluorescence intensity of WPU-DAN and DAN were increased by increasing temperature. Moreover, the fluorescence intensity of WPU-DAN emulsion was stable during 30 days and no loss of fluorescence intensity occurred for these days.

4"-p-N,N-Bis(2-hydroxyethyl)benzyl-3,3':6',2"-Terpyridine에 기초한 형광성 수분산 우레탄의 합성과 특성연구

4"-p-N,N-Bis(2-hydroxyethyl)benzyl-3,3':6',2"-Terpyridine에 기초한 형광성 수분산 우레탄의 합성과 특성연구

A novel 1,8-naphthalimide green fluorescent dye and its corresponding intrinsically fluorescent polyurethane latexes

A novel green fluorescent dye, 4-hexylamino-N-(2-hydroxy-1-hydroxymethylethyl)-1,8-naphthalimide (AHHNA), was designed and synthesized, and then used as a chain extender to prepare a series of intrinsically green fluorescent polyurethane (PU) latexes. The chemical structure of AHHNA and the properties of the fluorescent PU latexes and their films were characterized. It was found that the UV–Vis and the fluorescent spectra of the PUs remained fairly consistent with AHHNA, and the fluorescence emitting capacity of 1,8-naphthalimide group was enhanced by covalently bonding AHHNA onto the PU chain. The amount of AHHNA used in the latex preparation had no obvious effect on the latex colloid properties including particle size, poly index, and zeta potential. Results showed that the color difference (ΔE) and the extraction rate (R e) of the intrinsically fluorescent PU latex film were 5.72% and 3.1%, respectively, while the ΔE and R e of the extrinsically fluorescent PU latex film were 8.31% and 84.7%, respectively, indicating that the light fastness and the solvent fastness of the intrinsically fluorescent PU latex film were much better than those of the extrinsically fluorescent PU latex film.

Smart multifunctional polyurethane microcapsules for the quick release of anticancer drugs in BGC 823 and HeLa tumor cells.

Smart multifunctional drug delivery systems (DDSs) based on cytophilic fluorescent polyurethane copolymer microcapsules with high tumor cell internalization, triggered release, quick cancer cell death and real time fluorescent monitoring abilities is developed as a facile and versatile approach for precision cancer therapy.

Fluorescent PU films for detection and removal of Hg2 +, Cr3 + and Fe3 + ions

Three small molecular boron dipyrromethene (BODIPY) derivatives (B3a, B3b and B3c) were well-designed and synthesized at first, and then were incorporated into polyurethane to obtain macromolecular fluorescent sensors. These small molecular BODIPY derivatives exhibited high sensitivity and selectivity to Hg2+, Cr3+ and Fe3+ ions. The colors of these chemicals changed rapidly upon the addition of Hg2+, Cr3+ and Fe3+ ions. In addition, their fluorescence peaks shifted and was enhanced as well. B3a, B3b and B3c still remained the sensing properties when being introduced to polyurethane (PU). The functionalized PU films not only showed color change and fluorescence shift for detecting Hg2+, Cr3+ and Fe3+ ions as their small molecular counterparts, but also triggered a new emission peak in 500–600nm. Besides, the functionalized PU film (PU-B3a as a sample) could absorb Hg2+ ions more than 84mg/g in unit time and volume. It suggested that as long as the structure of the small molecular sensor was remained, the fluorescent ability remained even it is introduced to the macromolecular chains. In addition, Glass transition temperature (Tg) of the PU films changed when B3a, B3b and B3c were introduced.

Synthesis and Properties of Naphthalimide Fluorescent Dye and Covalent Fluorescent Polyurethane Emulsion

The reactive fluorescent dye 4- methoxy- N-(2- hydroxy- 1- hydroxymethylethyl) naphthalimide(MHHNA) was first synthesized by imidization and substitution reactions using 4-bromo-1,8-naphthalic anhydride,2- amino- 1,3- propanediol, and sodium methoxide as initial materials. A series of covalent fluorescent polyurethane(PU)(PU-MHHNA) emulsions were then fabricated using MHHNA as the chain extender through a phase inverse self-emulsification process. The chemical structure of the synthesized fluorescent dyes and the properties of PU-MHHNA emulsions and their latex films were characterized by1 H nuclear magnetic resonance(1H NMR) spectroscopy,13 C nuclear magnetic resonance(13C NMR) spectroscopy, Fourier transform infrared(FTIR) spectroscopy, elemental analysis, ultraviolet- visible(UV- Vis) absorption spectroscopy,fluorescent spectroscopy, particle size analysis, and xenon arc aging measurements. The fluorescent quantum yields of MHHNA and PU-MHHNA were 0.73 and 0.92, respectively. The amount of MHHNA had no obvious influence on the colloidal properties of the PU-MHHNA emulsions. The maximum wavelength(λmax) of the UVVis absorption spectra was 360.6 nm, and fluorescent spectroscopy analysis indicated that the maximum excitation wavelength(λex) and maximum emission wavelength(λem) of PU-MHHNA in acetone were 362 and435 nm, respectively. In addition, the fluorescence intensity of PU- MHHNA decreased with increasing temperature. The light fastness and solvent fastness of the PU-MHHNA film were much better than those of the non-covalent fluorescent polyurethane(PU/MBNA) film.

Pyrene-anchored ZnO nanoparticles through click reaction for the development of antimicrobial and fluorescent polyurethane nanocomposite

This work demonstrates the development of a multifunctional, antimicrobial and fluorescent polyurethane–ZnO hybrid nanocomposite coating with the aid of azide–alkyne click chemistry. Firstly, the surface of ZnO nanoparticles was successfully modified with 3-azidopropyltriethoxysilane coupling agent. The azide-terminated nanoparticles were then reacted with separately synthesized propargylpyrene in order to obtain pyrene-anchored ZnO nanoparticles. The size of the modified nanoparticles was measured using dynamic light scattering and field emission scanning electron microscopy. Thermogravimetric analysis showed that the thermal stability of the nanoparticles decreased with surface modification. The intensities of UV absorption and fluorescence emission were improved with an increase of pyrene units on the ZnO surface. These nanoparticles were incorporated into a triazole-rich hyperbranched polyurethane matrix in various weight percentages. It was observed that thermal stability and the intensity of UV absorption and fluorescence emission of the resulting polyurethane nanocomposite hybrid films were improved with loading of the modified nanoparticles. These hybrids are extremely resistant towards various bacterial and fungal attacks, which is attributed to the presence of the ZnO nanoparticles in the coatings. © 2014 Society of Chemical Industry

Synthesis and Fluorescent Performance of Fluorescein-functionalized Waterborne Polyurethane

A novel yellow fluorescent diisocyanate 3,6-di(hexamethylene urethano)spiro[xanthene-9,3′-phthalide] diisocyanate (DIX) was synthesized by the reaction of fluorescein with hexamethylene diisocyanate first. Using DIX to substitute partially isophorone diisocyanate (IPDI), a kind of yellow fluorescent waterborne polyurethane DIX-WPU was prepared by blocking the fluorophore of DIX into the polyurethane chain using IPDI, polytetramethylene ether glycol and 2,2-dimethylol propionic acid. The molecular structure of DIX and DIX-WPU was confirmed by means of Fourier transform infrared spectroscopy. The fluorophore is fixed permanently in the polyurethane chain and is difficult to migrate due to the covalent bonding with other component during the synthesis. The fluorescence intensity of DIX-WPU fluorescent dispersion was enhanced greatly comparing with that of fluorescein in a wide range of fluorophore content between 1 × 10–7 and 1 × 10–3 mol/L. The fluorescence of DIX-WPU dispersion is very stable not only for the long term storage but also for the fluorescence quencher. It was found that the fluorescence intensity of DIX-WPU increased with the increase of temperature.

Synthesis and fluorescence enhancement behavior of a novel fluorescent aqueous polyurethane emulsion DDAQ-TDI-PU

Abstract A novel fluorescent aqueous polyurethane emulsion DDAQ-TDI-PU was synthesized by blocking the anthraquinone moiety of 1,4-diamino-2,3-diphenoxyanthraquinone (DDAQ) into polyurethane chain using 2,4-tolylene diisocyanate (TDI), poly(propylene glycol) and 2,2-dimethylol propionic acid. The chain structure of DDAQ-TDI-PU was confirmed by means of Fourier transform infrared spectroscopy and UV–vis analysis. Comparing to the UV–vis spectrum of DDAQ, DDAQ-TDI-PU showed a hypsochromic shift from the absorption maxima of 518, 558, 609 nm to 510, 548, 586 nm, respectively. It was found that the fluorescence intensity of DDAQ-TDI-PU emulsion was enhanced greatly comparing with that of DDAQ. The fluorescence of DDAQ-TDI-PU was very stable not only for the long term storage but also for the fluorescence quencher.

Fluorescent Polyurethane Nanocapsules Prepared via Inverse Miniemulsion: Surface Functionalization for Use as Biocarriers

The functionalization of well-defined PU nanocapsules with an aqueous core prepared by performing a polyaddition at the interface of inverse (water-in-oil) miniemulsion droplets is demonstrated. The miniemulsion technique involving the nanoreactor concept allows one to obtain an encapsulation efficiency as high as 90% within the nanocapsules. A pH independent fluorescent dye is used as a model system for the aqueous core. By varying the molar ratio of the diol to the diisocyanate at a fixed surfactant concentration, the shell thickness of the nanocapsules can be finely tuned. The carboxy- and amino-functionalized surface of the nanocapsules can be tailored by an in-situ carboxymethylation reaction and by physical adsorption of a cationic polyelectrolyte, i.e. PAEMA or PEI. The increased uptake of amino-functionalized fluorescent nanocapsules by HeLa cells clearly demonstrates the potential of the functionalized nanocapsules to be successfully exploited as biocarriers.