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1.
Food Chem ; 459: 140358, 2024 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-39003852

RESUMEN

Betalains in beetroots offer notable colouring properties and health benefits, including antioxidant, anti-inflammatory, hepatoprotective, and antitumorous activities. However, they degrade due to processing and storage conditions like temperature, pH, oxygen, and light-exposure. Traditional betalain determination methods are resource-intensive solid-liquid extractions. This study proposes a novel approach using a smart polymer to rapidly quantify betalains in processed beetroots. The polymer, containing N,N-dimethylaminoethyl methacrylate, selectively interacts with compounds like betalains. Characterization shows thermal stability over 250 °C and suitable mechanical properties. The film changes to colour upon interaction with betalains, allowing quantification via smartphone. The sensory polymer's efficacy was validated across 27 beetroot samples, showing no significant differences compared to traditional methods. Combining the smart polymer with a colour analysis app, "Colorimetric Titration," provides a robust and efficient means of quantifying total betalains in beetroot puree, reducing the quantification time from 180 to 90 min, promising implications for routine food industry quality assessments.


Asunto(s)
Beta vulgaris , Betalaínas , Polímeros , Teléfono Inteligente , Betalaínas/química , Betalaínas/análisis , Beta vulgaris/química , Polímeros/química , Culinaria , Raíces de Plantas/química , Colorimetría
2.
J Hazard Mater ; 476: 135006, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38941828

RESUMEN

Water pollution from industrial or household waste, containing dyes from the textile industry, poses a significant environmental challenge requiring immediate attention. In this study, we have developed a crosslinked-smart-polymer film based on 2-(dimethylamino)ethyl methacrylate copolymerized with other hydrophilic and hydrophobic commercial monomers, and its efficacy in removing 21 different textile dyes was assessed. The smart polymer effectively interacts with and adsorbs dyes, inducing a noticeable colour change. UV-Vis spectroscopy analysis confirmed a removal efficiency exceeding 90 % for anionic dyes, with external diffusion identified as the primary influencing factor on process kinetics, consistent with both pseudo-first-order kinetics and the Crank-Dual model. Isothermal studies revealed distinct adsorption behaviors, with indigo carmine adhering to a Freundlich isotherm while others conformed to the Langmuir model. Permeation and fluorescence analyses corroborated isotherm observations, verifying surface adsorption. Significantly, our proof-of-concept demonstrated the resilience of the smart-film to common fabric softeners and detergents without compromising adsorption capacity. Additionally, the material exhibited reusability (for at least 5 cycles), durability, and good thermal and mechanical properties, with T5 and T10 values of 265 °C and 342 °C, respectively, a Tg of 168 °C, and a water swelling percentage of 54.3 %, thus confirming its stability and suitability for industrial application. ENVIRONMENTAL IMPLICATION: Dyes released during laundry processes should be classified as "hazardous materials" owing to their significant toxicity towards aquatic organisms, with the potential to disrupt ecosystems and harm aquatic biodiversity. This paper discusses the development of a novel acrylic material in film form, engineered to extract toxic anionic dyes. This study directly contributes to mitigating the environmental impact associated with the fashion industry and the domestic use of textiles. It can be implemented on both an industrial and personal scale, thereby encouraging more sustainable practices and promoting collaborative citizen science efforts towards.

3.
Sensors (Basel) ; 24(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38931634

RESUMEN

In recent years, sensory polymers have evolved significantly, emerging as versatile and cost-effective materials valued for their flexibility and lightweight nature. These polymers have transformed into sophisticated, active systems capable of precise detection and interaction, driving innovation across various domains, including smart materials, biomedical diagnostics, environmental monitoring, and industrial safety. Their unique responsiveness to specific stimuli has sparked considerable interest and exploration in numerous applications. However, along with these advancements, notable challenges need to be addressed. Issues such as wearable technology integration, biocompatibility, selectivity and sensitivity enhancement, stability and reliability improvement, signal processing optimization, IoT integration, and data analysis pose significant hurdles. When considered collectively, these challenges present formidable barriers to the commercial viability of sensory polymer-based technologies. Addressing these challenges requires a multifaceted approach encompassing technological innovation, regulatory compliance, market analysis, and commercialization strategies. Successfully navigating these complexities is essential for unlocking the full potential of sensory polymers and ensuring their widespread adoption and impact across industries, while also providing guidance to the scientific community to focus their research on the challenges of polymeric sensors and to understand the future prospects where research efforts need to be directed.

4.
ACS Appl Mater Interfaces ; 16(7): 9293-9302, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38324477

RESUMEN

Aramids, renowned for their high-performance attributes, find applications in critical fields such as protective equipment, aerospace components, and industrial filters. However, challenges arise in scenarios in which frequent washing is impractical, leading to bacterial proliferation, especially in textiles. This study outlines a straightforward and scalable method for preparing aramid-coated textiles and films endowed with inherent bactericidal activity, achieved by reacting parent aramids with vanillin. The functionalization of the aramids with bactericide moieties not only preserved the high-performance characteristics of commercial aramids but also improved their crucial mechanical properties. Tensile tests revealed an increase in Young's modulus, up to 50% compared to commercial m-aramid, accompanied by thermal performance comparable to commercial m-aramids. The evaluation of these coated textiles as bactericidal materials demonstrated robust effectiveness with A parameters (antibacterial activity) of 4.31 for S. aureus and 3.44 for K. pneumoniae. Reusability tests (washing the textiles in harsh conditions) underscored that the bactericide-coated textiles maintain their performance over at least 5 cycles. Regarding practical applications, tests performed with reconstructed human epidermis affirmed the nonirritating nature of these materials to the skin. The distinctive qualities of these metal-free intrinsic bactericidal aramids position them as ideal candidates for scenarios demanding a synergy of high performance and bactericidal properties. Applications such as first responders' textiles or filters stand to benefit significantly from these advanced materials.


Asunto(s)
Antibacterianos , Staphylococcus aureus , Humanos , Antibacterianos/farmacología , Textiles , Piel
5.
Polymers (Basel) ; 15(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37959995

RESUMEN

Gradient porous materials, particularly carbon-based materials, hold immense potential in the fields of batteries, energy storage, electrocatalysis, and sensing, among others, by synergistically combining the attributes associated with each pore size within a unified structural framework. In this study, we developed a gradient porous aramid (GP-Aramid) by incorporating cellulose acetate as a porosity promoter in the polymer casting solution in different proportions. These GP-Aramids were subsequently transformed into their pyrolyzed counterparts (GP-Pyramids), retaining their original structures while displaying diverse cellular or dense microstructures inherited from the parent aramid, as confirmed via scanning electron microscopy. X-ray diffraction spectra provided evidence of the conversion of aramids into carbonaceous materials. The materials showed structural defects observed through the intensity ratio of the G and D bands (ID/IG = 1.05) in the Raman spectra, while X-ray photoelectron spectra (XPS) revealed that the carbonization process yielded pyrolyzed carbon materials unusually rich in nitrogen (6%), oxygen (20%), and carbon (72%), which is especially relevant for catalysis applications. The pyrolyzed materials showed bulk resistivities from 5.3 ± 0.3 to 34.2 ± 0.6 depending on the meta- or para-orientation of the aramid and the porous structure. This work contributes to understanding these gradient porous aromatic polyamides' broader significance and potential applications in various fields.

6.
Polymers (Basel) ; 14(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36433081

RESUMEN

Polymers are extensively used in food and beverage packaging to shield against contaminants and external damage due to their barrier properties, protecting the goods inside and reducing waste. However, current trends in polymers for food, water, and beverage applications are moving forward into the design and preparation of advanced polymers, which can act as active packaging, bearing active ingredients in their formulation, or controlling the head-space composition to extend the shelf-life of the goods inside. In addition, polymers can serve as sensory polymers to detect and indicate the presence of target species, including contaminants of food quality indicators, or even to remove or separate target species for later quantification. Polymers are nowadays essential materials for both food safety and the extension of food shelf-life, which are key goals of the food industry, and the irruption of smart materials is opening new opportunities for going even further in these goals. This review describes the state of the art following the last 10 years of research within the field of food and beverage polymer's applications, covering present applications, perspectives, and concerns related to waste generation and the circular economy.

7.
Materials (Basel) ; 14(11)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34070343

RESUMEN

We describe the synthesis and characterization of three novel aromatic diamines containing oxyethylene sequences of different lengths. These diamines were polymerized using the low-temperature solution polycondensation method with isophthaloyl chloride (IPC), terepthaloyl chloride (TPC), [1,1'-biphenyl]-4,4'-dicarbonyl dichloride (BDC), and 4,4'-oxybis(benzoyl chloride) (OBE), obtaining twelve poly(ether amide)s with short segments of polydisperse polyethyleneoxide (PEO) sequences in the polymer backbone. These polymers show reasonably high molecular mass materials (Mw > 12,000), and the relationship between their structure and properties has been carefully studied. Compared with conventional polyamides containing monodisperse PEO sequences, the polydispersity of the PEO segments within the structural units exerts a significant influence on the crystallinity, flexibility, solubility, and the thermal properties of the polymers. For instance, the all-para oriented polyamides (TPCP-A), with an average number of 8.2 ethylenoxide units per structural unit can be transformed conventionally (Tm = 259 °C) in comparison with thermally untransformable polymer with 2 ethylenoxide units (Tm = 425 °C).

8.
Polymers (Basel) ; 12(8)2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32785165

RESUMEN

We prepared high-performance aromatic copolyamides, containing bithiazole and thiazolo-thiazole groups in their main chain, from aromatic diamines and isophthaloyl chloride, to further improve the prominent thermal behavior and exceptional mechanical properties of commercial aramid fibers. The introduction of these groups leads to aramids with improved strength and moduli compared to commercial meta-oriented aromatic polyamides, together with an increase of their thermal performance. Moreover, their solubility, water uptake, and optical properties were evaluated in this work.

9.
Polymers (Basel) ; 9(9)2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30965723

RESUMEN

We describe herein the state of the art following the last 8 years of research into aromatic polyamides, wholly aromatic polyamides or aramids. These polymers belong to the family of high performance materials because of their exceptional thermal and mechanical behavior. Commercially, they have been transformed into fibers mainly for production of advanced composites, paper, and cut and fire protective garments. Huge research efforts have been carried out to take advantage of the mentioned characteristics in advanced fields related to transport applications, optically active materials, electroactive materials, smart materials, or materials with even better mechanical and thermal behavior.

10.
Chem Commun (Camb) ; 50(19): 2484-7, 2014 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-24457981

RESUMEN

This study developed sensory polymeric materials for the colorimetric sensing of TNT in aqueous media. Solid films and coated fabrics permitted the detection of TNT, through colour change, and its quantification, by taking a picture of the materials and processing their RGB parameters to define the evolved colour.

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