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1.
J Fluoresc ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153169

RESUMO

Fluorescent polyurethane has been widely used as fluorescent probes and switches due to its diverse structure and properties, but most of them are solvent-based and synthesized from petroleum-based products. A new type of rosin-based anthraquinone fluorescent waterborne polyurethane (WPU-DAAQ) with good and stable fluorescence properties was synthesized by reacting rosin modified ester (RAG) as a diol and 2, 6-diaminoanthraquinone (DAAQ) as a fluorescent agent with diisocyanate. The structure of WPU-DAAQ was characterized by Fourier transform infrared spectroscopy, UV-vis absorption spectroscopy, and hydrogen magnetic resonance spectroscopy. The fluorescence properties, water resistance, and solvent resistance of WPU-DAAQ were tested. The results showed that DAAQ was successfully grafted onto the polyurethane molecular chain. The fluorescence intensity of WPU-DAAQ increases and then decreases with increasing excitation wavelengths, and increases with the increase of solvent ether content, and is significantly enhanced compared to DAAQ. The dispersion stability was good with the increase of DAAQ. The introduction of DAAQ into polyurethane improved the thermal stability, hydrophobicity, and solvent resistance of WPU-DAAQ. Therefore, WPU-DAAQ is a new type of fluorescent waterborne polyurethane with stable dispersion properties, good fluorescent properties, heat resistance and water resistance.

2.
Int J Biol Macromol ; 273(Pt 2): 133152, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878928

RESUMO

The design of polymer-based composites possessing good mechanical and self-healing properties remains a challenge in the development of high-performance self-healing materials. In this study, we used two-dimensional polyamide (2DPA), biomass rosin ester, and a dynamic crosslinking agent poly (urethane-urea) as raw materials, and prepared biomass rosin-based composites via in situ polymerization. The composites with 1 wt% 2DPA exhibited excellent self-healing properties (self-healing efficiency of 94 % after 24 h at 80 °C) and mechanical properties (tensile strength = 7.8 MPa). Moreover, the composites were applied to anticorrosion and antimicrobial coatings, which possessed excellent anticorrosion and antimicrobial properties. This study provides a new strategy for developing high-performance bio-based self-healing composites.


Assuntos
Anti-Infecciosos , Nylons , Resinas Vegetais , Nylons/química , Resinas Vegetais/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Resistência à Tração , Poliuretanos/química
3.
J Fluoresc ; 33(4): 1593-1602, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36790631

RESUMO

Rosin-based fluorescent polyurethane emulsion (FPU) was prepared using isophorone diisocyanate, ester of acrylic rosin and glycidyl methacrylate, 1,5-dihydroxy naphthalene (1,5-DN), and 1,4-butanediol as the raw materials. Then, rosin-based fluorescent polyurethane microspheres (FPUMs) were successfully prepared by suspension polymerization method using FPU as the main material, azodiisobutyronitrile as the initiator, and gelatin as the dispersant. FPUMs were characterized by Fourier transform infrared spectra, thermogravimetric analysis, optical microscopy, scanning electron microscopy and fluorescence spectra, and the response performance of FPUMs to pH was studied. The results showed that FPUMs were successfully prepared. With the increase of the level of 1,5-DN, the particle size of FPUMs increased gradually, and the fluorescence intensity increased first and then decreased. When the level of 1,5-DN was 3 wt.%, the average particle size was 49.3 µm, the particle distribution index (PDI) was 1.05, and the fluorescence intensity was the largest (3662 a.u.). The fluorescence intensity of FPUMs increased linearly with the decrease of pH, which can be used for pH detection in solution. Furthermore, the FPUMs exhibited good thermal stability, anti-interference and recoverability.

4.
ACS Omega ; 6(1): 476-482, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33458499

RESUMO

In this paper, a waste fluid catalytic cracking (FCC) catalyst is used as a carrier to prepare a supported non-noble metal nickel catalyst (Ni/wFCC), which is applied to the selective hydrogenation of citral to citronellal. X-ray powder diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used to analyze the structural characteristics of the Ni-loaded sample. The catalyst after loading Ni still maintained a good zeolite structure, and the surface impurities were reduced. The effect of reaction conditions on the Ni/wFCC-catalyzed hydrogenation of citral to citronellal was investigated, and the optimal reaction conditions were obtained as follows: a Ni loading of 20 wt %, a catalyst amount of 5.6%, a hydrogenation temperature of 180 °C, a hydrogenation time of 90 min, and a hydrogenation pressure of 3.0 MPa. Under these conditions, the conversion of citral and selectivity of citronellal were 98.5 and 86.6%, respectively, indicating that the Ni/wFCC catalyst had strong catalytic activity and selectivity. This research provided new ideas for the recycling of waste FCC catalysts and industrial synthesis of citronellal.

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