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Carbohydrate Polymers Nov 2023The healing of wounds in diabetic patients is a huge challenge issue in clinical medicine due to the disordered immune. Recruiting endogenous cells to play a role in the...
The healing of wounds in diabetic patients is a huge challenge issue in clinical medicine due to the disordered immune. Recruiting endogenous cells to play a role in the early stage and timely reducing inflammation to promote healing in the middle or late of injuring are both prerequisites for effective treatment. Here, inspired by natural extracellular matrix, three-dimensional porous polyurethane-hyaluronic acid hybrid hydrogel scaffolds (PUHA) were prepared to repair diabetic wound through activate cell immunity by moderate foreign body reaction, provide cell adhesion growth extracellular matrix of hyaluronic acid (HA) and exhibit anti-inflammatory effect of polyurethane (PU). The interaction between PU and HA alters the compact PU hydrogel into macroporous PUHA hydrogel scaffolds with super-swelling, elastic mechanical properties, and controllable degradation, which are suitable for endogenous cells infiltration, growth and immune activation. Additionally, incorporating with RGD, PUHA hydrogel scaffolds with bioactive physicochemical features can evidently reduce the inflammation and modulate the polarization of macrophage apparently both in vitro and in vivo, mainly through downregulation of cytokine-cytokine receptor interaction genes, leading to reprogramming immune-microenvironment and rapid diabetic wound healing. This method of gathering cells initially and intervening immune-microenvironment in time provides an expected way to design biomaterials for chronic wound healing.
Topics: Humans; Hyaluronic Acid; Polyurethanes; Hydrogels; Inflammation; Biocompatible Materials; Diabetes Mellitus
PubMed: 37659799
DOI: 10.1016/j.carbpol.2023.121238 -
Polymers Sep 2023Aqueous polyurethane is an environmentally friendly, low-cost, high-performance resin with good abrasion resistance and strong adhesion. Cationic aqueous polyurethane is...
Aqueous polyurethane is an environmentally friendly, low-cost, high-performance resin with good abrasion resistance and strong adhesion. Cationic aqueous polyurethane is limited in cathodic electrophoretic coatings due to its complicated preparation process and its poor stability and single performance after emulsification and dispersion. The introduction of perfluoropolyether alcohol (PFPE-OH) and light curing technology can effectively improve the stability of aqueous polyurethane emulsions, and thus enhance the functionality of coating films. In this paper, a new UV-curable fluorinated polyurethane-based cathodic electrophoretic coating was prepared using cationic polyurethane as a precursor, introducing PFPE-OH capping, and grafting hydroxyethyl methacrylate (HEMA). The results showed that the presence of perfluoropolyether alcohol in the structure affected the variation of the moisture content of the paint film after flash evaporation. Based on the emulsion particle size and morphology tests, it can be assumed that the fluorinated cationic polyurethane emulsion is a core-shell structure with hydrophobic ends encapsulated in the polymer and hydrophilic ends on the outer surface. After abrasion testing and baking, the fluorine atoms of the coating were found to increase from 8.89% to 27.34%. The static contact angle of the coating to water was 104.6 ± 3°, and the water droplets rolled off without traces, indicating that the coating is hydrophobic. The coating has excellent thermal stability and tensile properties. The coating also passed the tests of impact resistance, flexibility, adhesion, and resistance to chemical corrosion in extreme environments. This study provides a new idea for the construction of a new and efficient cathodic electrophoretic coating system, and also provides more areas for the promotion of cationic polyurethane to practical applications.
PubMed: 37765579
DOI: 10.3390/polym15183725 -
International Journal of Molecular... Dec 2023Due to the growing interest in biopolymers, biosynthesizable and biodegradable polymers currently occupy a special place. Unfortunately, the properties of native...
Due to the growing interest in biopolymers, biosynthesizable and biodegradable polymers currently occupy a special place. Unfortunately, the properties of native biopolymers make them not good enough for use as substitutes for conventional polymers. Therefore, attempts are being made to modify their properties. In this work, in order to improve the properties of the poly(3-hydroxybutyrate) (P3HB) biopolymer, linear aliphatic polyurethane (PU) based on 1,4-butanediol (BD) and hexamethylene 1,6-diisocyanate (HDI) was used. The conducted studies on the effect of the amount of PU used (5, 10, 15 and 20 m/m%) showed an improvement in the thermal properties of the prepared polymer blends. As part of the tested mechanical properties of the new polymer blends, we noted the desired increase in the tensile strength, and the impact strength showed a decrease in hardness, in particular at the presence of 5 m/m% PU. Therefore, for further improvement, hybrid nanobiocomposites with 5 m/m% PU and organically modified montmorillonite (MMT) (Cloisite 30B) were produced. The nanoadditive was used in a typical amount of 1-3 m/m%. It was found that the obtained nanobiocomposites containing the smallest amount of nanofillers, i.e., 1 m/m% Cloisite30B, exhibited the best mechanical and thermal properties.
Topics: Polymers; Polyurethanes; Bentonite; 3-Hydroxybutyric Acid; Biopolymers
PubMed: 38139234
DOI: 10.3390/ijms242417405 -
International Journal of Biological... Sep 2023Lignin is a natural polymer with abundant functional groups with great application prospects in lignin-based polyurethane elastomers with self-healing abilities. In this...
Lignin is a natural polymer with abundant functional groups with great application prospects in lignin-based polyurethane elastomers with self-healing abilities. In this study, a lignin self-healing polyurethane (PUDA-L) was specially designed using lignin as the raw material of polyurethane, combining lignin with Diels-Alder (DA) bond and hydrogen bonds. The experimental results showed that PUDA-L was prepared with good thermal stability, fatigue resistance, shape memory effect, excellent mechanical strength, and self-healing ability by partially replacing the crosslinking agents with bio-based lignin and hydroxylated modified lignin to increase the hydroxyl content. Polyurethane has a tensile strength of up to 29 MPa and an elongation at break of up to 500 %. The excellent self-healing ability of PUDA-L originates from the internal DA bonds and cross-linked hydrogen bonds. After the dumbbell sample was fused and heated at 130 °C for 4 h, the elastomer could be completely healed, the tensile strength was restored to 29 MPa, and the self-healing efficiency was up to 100 %. The developed PUDA-L elastomer has promising applications in sensors and smart skins.
Topics: Polyurethanes; Lignin; Elastomers; Prunella; Hot Temperature
PubMed: 37499717
DOI: 10.1016/j.ijbiomac.2023.125925 -
Journal of the College of Physicians... Sep 2023The aim of this study was to evaluate the effect of modifying the cuff on preventing ventilator-associated pneumonia (VAP). PubMed, Embase and Cochrane Library were... (Review)
Review
The aim of this study was to evaluate the effect of modifying the cuff on preventing ventilator-associated pneumonia (VAP). PubMed, Embase and Cochrane Library were systematically searched from inception to April 2022, for randomised controlled trials (RCTs) that compared the effect of a new type of cuff intubation with traditional cuff intubation on VAP incidence and intensive-care unit (ICU) mortality in mechanically ventilated patients. Nine RCTs with 1937 patients were finally evaluated. The pooled results for the incidence of VAP showed that the modified cuff significantly decreased the morbidity of VAP compared with the traditional cuff (relative ratio (RR) = 0.73, 95% confidence interval (CI) 0.56-0.95, p = 0.02). The subgroup analysis revealed that polyurethane (PU) cuff (RR = 0.82, 95% CI 0.46-1.48, p = 0.52), conical cuff (RR = 0.97, 95% CI 0.73-1.28, p = 0.82) and PU-conical cuff (RR = 1.36, 95% CI 0.85-2.18, p = 0.20) did not decrease the incidence of VAP. Moreover, the improved cuff combined with subglottic secretion drainage (SSD) could significantly reduce the VAP incidence (RR = 0.58, 95% CI 0.44-0.77, p = 0.0001). In terms of ICU mortality, there was no statistically significant difference (RR = 0.83, 95% CI 0.68-1.02, p = 0.08) between the two groups. The modified cuff is superior to the traditional cuff in VAP prevention. In particular, the modified cuff combined with subglottic secretion drainage has more advantages. Key Words: Ventilator-associated pneumonia, Intubation, Endotracheal cuff, Intensive care unit, Meta-analysis.
Topics: Humans; Intensive Care Units; Intubation, Intratracheal; Pneumonia, Ventilator-Associated; Polyurethanes
PubMed: 37691369
DOI: 10.29271/jcpsp.2023.09.1050 -
The Science of the Total Environment Aug 2023Rapid accumulation of end-of-life polyurethanes (PUR) in the environment is a global crisis. While biodegradation of PUR has been reported, the process is slow, and the...
Rapid accumulation of end-of-life polyurethanes (PUR) in the environment is a global crisis. While biodegradation of PUR has been reported, the process is slow, and the microbiology involved in PUR biodegradation is poorly understood. This study reported the microbial community involved in PUR biodegradation (designed as PUR-plastisphere) in estuary sediments, and isolation and characterization of two PUR-utilizing isolates. PUR foams were pretreated with oxygen plasma (referred as p-PUR foams) to mimic weathered conditions before embedded in microcosms containing estuary sediments. After 6 months of incubation, a substantial loss of ester/urethane bonds on the embedded p-PUR foams was observed, according to Fourier transform infrared (FTIR) spectroscopy. Analysis of PUR-plastisphere showed two dominant genera, Pseudomonas (2.7 %) and Hyphomicrobium (3.0 %), along with many unknown genera in Sphingomonadaceae (9.2 %), and predicted hydrolytic enzymes such as esterases and proteases. Purpureocillium sp., and Pseudomonas strain PHC1 (designated as strain PHC1 hereafter), isolated from the PUR plastisphere, can grow on Impranil (a commercial water-borne PUR) as a sole nitrogen or carbon source. High esterase activities were detected in the spent Impranil-containing media, and a significant loss of ester bonds of the spent Impranil was also observed. After 42 days of incubation, the strain PHC1-inoculated p-PUR foam showed a noticeable development of biofilm as observed via scanning electron microscopy (SEM), and disappearance of ester and urethane bonds of the PUR as detected by FTIR, supporting the role of strain PHC1 in biodegradation of the p-PUR foam. Also, the FTIR spectra observed for the sediment-embedded p-PUR foams was similar to those for the strain PHC1-inoculated p-PUR foams, suggesting the potential role of the dominant species of Pseudomonas in PUR-plastisphere. The results of this study showed the promise of rapid biodegradation of PUR foam through inoculating with a PUR-utilizing isolate, Pseudomonas strain PHC1.
Topics: Polyurethanes; Pseudomonas; Biodegradation, Environmental; Soil Microbiology; Esterases; Amides
PubMed: 37156380
DOI: 10.1016/j.scitotenv.2023.163932 -
Environmental Research Jul 2024Gas separation membranes are critical in a variety of environmental research and industrial applications. These membranes are designed to selectively allow some gases to... (Review)
Review
Gas separation membranes are critical in a variety of environmental research and industrial applications. These membranes are designed to selectively allow some gases to flow while blocking others, allowing for the separation and purification of gases for a variety of applications. Therefore, the demand for fast and energy-efficient gas separation techniques is of central interest for many chemical and energy production diligences due to the intensified levels of greenhouse and industrial gases. This encourages the researchers to innovate techniques for capturing and separating these gases, including membrane separation techniques. Polymeric membranes play a significant role in gas separations by capturing gases from the fuel combustion process, purifying chemical raw material used for plastic production, and isolating pure and noncombustible gases. Polyurethane-based membrane technology offers an excellent knack for gas separation applications and has also been considered more energy-efficient than conventional phase change separation methodologies. This review article reveals a thorough delineation of the current developments and efforts made for PU membranes. It further explains its uses for the separation of valuable gases such as carbon dioxide (CO), hydrogen (H), nitrogen (N), methane (CH), or a mixture of gases from a variety of gas spillages. Polyurethane (PU) is an excellent choice of material and a leading candidate for producing gas-separating membranes because of its outstanding chemical chemistry, good mechanical abilities, higher permeability, and variable microstructure. The presence of PU improves several characteristics of gas-separating membranes. Selectivity and separation efficiency of PU-centered membranes are enhanced through modifications such as blending with other polymers, use of nanoparticles (silica, metal oxides, alumina, zeolite), and interpenetrating polymer networks (IPNs) formation. This manuscript critically analyzes the various gas transport methods and selection criteria for the fabrication of PU membranes. It also covers the challenges facing the development of PU-membrane-based separation procedures.
Topics: Polyurethanes; Membranes, Artificial; Gases; Air Pollutants
PubMed: 38636643
DOI: 10.1016/j.envres.2024.118953 -
Biopolymers Dec 2023Currently, conventional plastics are necessary for a variety of aspects of modern daily life, including applications in the fields of healthcare, technology, and... (Review)
Review
Currently, conventional plastics are necessary for a variety of aspects of modern daily life, including applications in the fields of healthcare, technology, and construction. However, they could also contain potentially hazardous compounds like isocyanates, whose degradation has a negative impact on both the environment and human health. Therefore, researchers are exploring alternatives to plastic which is sustainable and environmentally friendly without compromising its mechanical and physical features. This review study highlights the production of highly eco-friendly bioplastic as an efficient alternative to non-biodegradable conventional plastic. Bioplastics are produced from various renewable biomass sources such as plant debris, fatty acids, and oils. Poly-addition of di-isocyanates and polyols is a technique employed over decades to produce polyurethanes (PUs) bioplastics from renewable biomass feedstock. The toxicity of isocyanates is a major concern with the above-mentioned approach. Novel green synthetic approaches for polyurethanes without using isocyanates have been attracting greater interest in recent years to overcome the toxicity of isocyanate-containing raw materials. The polyaddition of cyclic carbonates (CCs) and polyfunctional amines appears to be the most promising method to obtain non-isocyanate polyurethanes (NIPUs). This method results in the creation of polymeric materials with distinctive and adaptable features with the elimination of harmful compounds. Consequently, non-isocyanate polyurethanes represent a new class of green polymeric materials. In this review study, we have discussed the possibility of creating novel NIPUs from renewable feedstocks in the context of the growing demand for efficient and ecologically friendly plastic products.
Topics: Humans; Polyurethanes; Isocyanates; Biopolymers; Amines; Biomass
PubMed: 37846654
DOI: 10.1002/bip.23568 -
Materials (Basel, Switzerland) Oct 2023The goal of this research was to investigate the effect of different types of nanoparticles on the UV weathering resistance of polyurethane (PU) treatment in...
The goal of this research was to investigate the effect of different types of nanoparticles on the UV weathering resistance of polyurethane (PU) treatment in polyester-based fabrics. In this regard, zinc oxide nanoparticles (ZnO), hydrophilic silica nanoparticles (SiO (200)), hydrophobic silica nanoparticles (SiO (R812)), and carbon nanotubes (CNT) were mixed into a waterborne polyurethane dispersion and impregnated into textile samples. The puncturing resistance of the developed specimens was examined before and after UV-accelerated aging. The changes in chemical structure and surface appearance in nanoparticle-containing systems and after UV treatments were documented using microscopic pictures and infrared spectroscopy (in attenuated total reflectance mode). Polyurethane impregnation significantly enhanced the puncturing strength of the neat fabric and reduced the textile's ability to be deformed. However, after UV aging, mechanical performance was reduced both in the neat and PU-impregnated specimens. After UV treatment, the average puncture strength of all nanoparticle-containing systems was always greater than that of aged fabrics impregnated with PU alone. In all cases, infrared spectroscopy revealed some slight differences in the absorbance intensity of characteristic peaks for polyurethane polymer in specimens before and after UV rays, which could be related to probable degradation effects.
PubMed: 37959441
DOI: 10.3390/ma16216844 -
Mass Spectrometry Reviews Aug 2023This article reviews the analytical tool chest used for characterizing alkoxylates and their associated copolymer mixtures. Specific emphasis will be placed upon the use... (Review)
Review
This article reviews the analytical tool chest used for characterizing alkoxylates and their associated copolymer mixtures. Specific emphasis will be placed upon the use of mass spectrometry-based techniques as rapid characterization tools for optimizing reaction processes in an industrial R&D setting. An initial tutorial will cover the use of matrix-assisted laser desorption/ionization-mass spectrometry and tandem mass spectrometry fragmentation for detailed component analysis (e.g., polyol and isocyanate) of a model polyurethane-based foam. Next, this critical feedback information will be used with the guidance of mass spectrometry to initiate the development of a new, more efficient, tris(pentafluorophenyl)borane (FAB) catalyst-based alkoxylation process for generating the next generation of glycerin-initiated poly(propylene oxide)-co-poly(ethylene oxide) copolymers. Examples will be provided for each step in the FAB-based optimization process that were required to generate the final product. Following this example, two-dimensional liquid chromatography, supercritical fluid chromatography, and ion mobility separations, along with their coupling to mass spectrometry, will be reviewed for their efficiency in characterizing and quantitating the components within these complex polyether polyol mixtures.
PubMed: 37533397
DOI: 10.1002/mas.21862