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This paper investigates delivery of encapsulated drug from poly lactic-co-glycolic micro-/nano-particles. Experimental data collected from about 50 papers are analyzed by machine learning algorithms including linear regression, principal component analysis, Gaussian process regression, and artificial neural networks. The focus is to understand the effect of drug solubility, drug molecular weight, particle size, and pH-value of the release matrix/environment on drug release profiles. The results obtained from machine learning is then used as guidelines for designing new in vitro experiments to examine dependence of drug release profiles on those four factors. It is interesting to see that indeed the results of the new in vitro experiments are in basic agreement with the results obtained from machine learning. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) were produced directly from hemp agro-waste (HAW) using ammonium persulfate (APS) oxidation. Industrial hemp growth in the US has been accompanied with HAW production. While hemp has previously been shown as a source for CNCs, studies on CNCs from HAW (specifically hemp hurd) have not been reported on. Furthermore, studies on the mechanical characteristics of individual CNCs extracted using APS are lacking. Herein, the one-step oxidation treatment was followed by a purification step to remove impurities and hence to colloidally stabilize CNCs in aqueous suspensions, then analysis of the morphological and mechanical properties was performed. Purified and unpurified CNC samples were compared for potential differences in morphological and mechanical properties. Morphological analysis was performed using atomic force microscopy (AFM): purified CNCs had an average length of 183.1 ± 73.9 nm, unpurified CNCs had an average length of 202.0 ± 79.2, and both samples had an average diameter of 4 ± 2 nm. Mechanical analysis of individual CNCs using force-distance spectroscopy (FDS) suggested both samples had little differences with average values of Young's modulus 2.19 ± 0.15 GPa, maximum loading force of 6.29 ± 0.09 nN, and adhesion energy of 1.57 ± 1.12e-16 J. No statistical differences between purified and unpurified CNCs were found in Young's modulus and maximum loading forces measurements, suggesting the impurities had minimum impact on mechanical strength. These results highlight the potential for mechanical assessment of individual CNCs extracted using APS from HAW via FDS and the need for further exploration into the methodology of this type of mechanical analysis. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA) was modified using D‐mannitol (DM) and 1‐butyl‐3‐methylimidazole bromide (BMIMBr) as the complex plasticizer (DB), and PVA/DB composite was prepared. The plasticizing effect of DB on PVA was studied by Fourier transform infrared spectroscopy (FT‐IR), differntial scanning calorimetry (DSC), thermos gravimetric analysis (TGA) and melt flow indexer (MI). FT‐IR analysis indicated that Br− of BMIMBr and OH of DM could form H‐bonds with OH of PVA. With the increase of DB, the melt temperature (Tm2) and crystallization temperature (Tc1) of PVA/DB composite decreased, the initial thermal decomposition temperatures (Td), thermal processing window (ΔT) and MI values increased respectively. Based on above studies, the influence of DB content on rheological properties of PVA/DB composite was investigated by the capillary rheometer. The result displayed that apparent viscosity of PVA/DB composite decreased with increasing DB content, shear rate and measured temperature. The non‐Newtonian index (n) increased and structural viscosity index (Δη) decreased with the increase of measured temperature and DB. The viscous flow activation energy (Eη) decreased as the shear rate and DB content increased. When the measured temperature, DB content and shear rate were in the range of Tm2+30 −Tm2+35 °C, 40–50 wt% and 764.8–1504.9 s−1, respectively, the spinnability of PVA/DB composite was optimal, which will lay a theoretical foundation for the exploration of melt spinning process in the future. [ABSTRACT FROM AUTHOR]

Large-diameter polyvinyl alcohol (PVA) fiber has a broad application prospect in the field of reinforcing geomorphic building materials owing to its large diameter and excellent mechanical properties. In this work, PVA2499 polymer was used as the raw material, DMSO/H2O as the hybrid solvent, and the staged heating approach was adopted to obtain high solid content of spinning solutions, and then a series of large-diameter medium-strength PVA fibers with different solid contents of spinning solutions (SCS) were prepared by dry-wet spinning, and the Fourier transform infrared spectroscopy (FTIR), scan electron microscope (SEM), differential scanning calorimetry (DSC), thermal analysis (TGA), X-ray diffractometer (XRD) and electronic universal testing machine were performed to explore the effect of the SCS on the structure and performance of PVA fiber. The results displayed that with the increase of the SCS, the -OH stretching vibration absorption peak of PVA fiber moved from 3276 cm−1 to 3262 cm−1; The tensile strength, initial modulus, the crystallization and orientation of PVA fibers all increased first and then decreased. Especially, when the SCS was 23.5wt%, the diameter of the PVA fiber was 110.6 ± 6.0 μm (124.8 ± 6.2 dtex), the tensile strength was 7.0 ± 0.3 cN/dtex, the initial modulus was 106.2 ± 10.3 cN/dtex, the crystallization and the orientation were 49.6% and 96.8%, respectively. [ABSTRACT FROM AUTHOR]

The development of wound-dressing materials has attracted significant research interests in recent years. With the advancement of nanofabrication, the application of nanoparticles (NPs) in drug delivery systems has become feasible. However, most existing work focuses on incorporation of metal, metal/semi-metal oxide, or organic particles into nanofiber scaffolds. There has been a lack of work on the incorporation of drug-encapsulated polymeric particles into nanofiber scaffolds. In this study, gentamicin-encapsulated poly-(lactic-co-glycolic acid) (PLGA) NPs were synthesized via a double emulsion solvent evaporation method. Electrospinning was used to incorporate gentamicin-encapsulated PLGA NPs into nanofiber scaffolds. Atomic force microscopy (AFM), dynamic light scattering, scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV–vis), and an agar diffusion method were utilized to characterize the morphologies, release profiles, and antibacterial activities of various gentamicin-loaded PLGA NP-incorporated nanofiber scaffolds. The results indicated that the PLGA NPs had a spherical morphology with an average diameter of 130 nm. Purification of PLGA NPs was essential to eliminate the residual poly-(vinyl alcohol) (PVA) and to prevent particle agglomeration. The purified PLGA NPs were uniformly and individually incorporated into the polyurethane (PU)/ poly-(ethenyl oxide) (PEO) or PEO-only nanofiber scaffolds but nearly none into the PU-only fiber scaffolds. PEO served as a continuous phase in the PU/PEO mixture, which significantly improved the compatibility of PLGA NPs and PU, resulting in a well-dispersed distribution of PLGA NPs in the monolithic nanofiber scaffolds. Excellent antibacterial properties against Escherichia coli were found in both PU/PEO and PEO nanofiber scaffolds. This study of incorporating gentamicin-encapsulated PLGA NPs into fiber scaffolds provides insights for achieving successful incorporation of drug-encapsulated polymeric NPs into fiber scaffolds. This offers a promising microfabrication technology for delivery of therapeutic molecules with controlled release for biomedical applications. [ABSTRACT FROM AUTHOR]

High mechanical property poly (vinyl alcohol) (PVA) fibers have attracted tremendous attentions because of their excellent mechanical properties and has a potential application in the field of building enhancement. In this article, PVA polymer with high polymerization degree (Pn) and high Syndiotacticity-diad content (S-diad) were synthesized using vinyl acetate (VAc) and vinyl pivalate (VPi) as monomers via emulsion polymerization with water as solvent, the GPC and 1H NMR were used to characterized the Pn and S-diad of PVA polymer. Then the lanthanum chloride (LaCl3) was chosen as cross-linking and the synthesized PVA polymer as raw material for dry-wet spinning, a series of PVA fibers with high strength and high modulus have been prepared. The final PVA-La fibers were characterized through a series of experiments including of FTIR, SEM, DSC, TGA, XRD and fiber tensile tester. It turned out that the Pn and S-diad of synthesized PVA polymer were 4817 ± 76 and 56.3 ± 0.7%. With the increasing of LaCl3 content, the -OH vibration absorption peak of PVA-La composite fiber gradually increased from 3462 cm-1 to 3484 cm-1; the strength, modulus, crystallinity and orientation all increased first and then decreased. Especially, the properties of PVA-La fiber exhibited an optimal LaCl3 content of 0.8 wt%, the denier was 5.4 ± 0.5 dtex, the tensile strength and highest elastic modulus of 15.19 ± 0.5 cN/dtex and 369.21 ± 9.1cN/dtex, the elongation at break was 3.72 ± 0.4%, the crystallinity was 53.9 ± 0.6%, the orientation was 95.6 ± 0.6%. [ABSTRACT FROM AUTHOR]

Different vinyl acetate (VAc) and vinyl benzoate (VBz) monomer ratios have been chosen as monomers to create high polymerization degree (Pn) and high syndiotacticity‐diad content (S‐diad) poly(vinyl alcohol) (PVA) polymers via emulsifier‐free polymerization in order to address the problem of limited mechanical capabilities of PVA fibers prepared with low Pn and low S‐diad polymer. The variations in hydrogen bonding, Pn, S‐diad, and viscosity of different PVA polymers were investigated and evaluated using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, gel permeation chromatography, and a viscosity tester. Moreover, various PVA fibers with high strength and modulus have been manufactured using a synthetic polymer as the raw material for dry‐wet spinning. The effect of Pn and S‐diad on the mechanical and thermal characteristics of PVA fibers is evaluated using a variety of characterization techniques, such as the scanning electron microscope, differential scanning calorimetry, thermogravimetric analyzer, X‐ray diffraction, and tensile tester. As the ratio of VBz monomer increased, the results suggested that VBz may have a considerable impact on the Pn and S‐diad of PVA polymers, the OH vibration absorption peak reduced from 3491 to 3442 cm−1; the Pn increased from 2112 to 17,704; and the S‐diad rose from 51.2% to 60.1%. In addition to the fact that Pn and S‐diad significantly increased the fibers' strength and modulus, the crystallinity increased from 41.8% to 51.7%, and the orientation degree rose from 87.5% to 91.7%, as Pn and S‐diad increased; the tensile strength and highest elastic modulus increased from 9.71 ± 0.3 cN/dtex to 12.74 ± 0.5 cN/dtex (increased of 31.2%) and 264.52 ± 9.3 cN/dtex to 338.41 ± 8.6 cN/dtex (increased of 27.9%); the elongation at break decreased from 5.63 ± 0.3% to 2.92 ± 0.2%. [ABSTRACT FROM AUTHOR]

Colorimetric biosensors made by polydiacetylene nanofibers have been of great interest in developing novel strategies of rapid and in situ detection to bacterial infection that is a major concern for human fatalities around the world. Previous studies have focused on bacterial detection and the sensitivity of the detection that the PDA biosensors can offer. However, the selectivity of the detection to different bacterial strains has not been well understood. With the recent emergence of multiple drug-resistance bacterial strains, selective detection of bacteria demands more attention and cutting-edge tools. In this study, a polydiacetylene (PDA) nanofiber biosensor prepared via electrospinning was found effectively to offer selective detection of Gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa via a rapid blue-to-red colorimetric change. The quantification of the colorimetric changes suggested that the biosensor selectivity was effective in identifying with Gram-negative bacteria over Gram-positive bacteria (Staphylococcus aureus). The selectivity was likely due to structural differences between Gram-positive bacteria and Gram-negative bacteria such as cell outer layer thickness, as well as different extracellular polymeric substances (EPS) released by different bacteria. In addition, the nanofiber biosensor demonstrated superior antibacterial properties that were evaluated using bacteria staining and electron microscopic techniques. A comprehensive analysis of the interaction between the PDA nanofibers and different bacteria was presented to provide insightful understanding of selective detection and antibacterial properties of the PDA nanofibers. The results suggested that PDA nanofibers have great potential in medical textiles, personal protective equipment, and other biomedical applications. [ABSTRACT FROM AUTHOR]

PVA/IL composites were successfully prepared with an ionic liquid (IL), 1‐butyl‐3‐methylimidazolium bromide and poly(vinyl alcohol) (PVA). The plasticizing effect of IL on PVA was investigated using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X‐ray diffraction (XRD), thermogravimetric analysis (TGA) and melt flow index (MI) measurements. FTIR analysis indicated that the anion (Br−) of IL could form hydrogen bonds with the hydroxyl groups of PVA. With an increase of IL, –OH absorption peaks of PVA/IL composites shifted to higher wavenumbers. DSC analysis showed that both melt and crystallization temperatures of the PVA/IL composites decreased as IL content increased. XRD analysis showed that the degree of crystallinity of the PVA/IL composites had a decreasing trend with an increase of IL. TGA showed that IL could effectively improve the thermal stability of PVA. The thermal stability of the PVA/IL composites decreased gradually with increasing IL content, but was higher than that of PVA. Thermal processing window (ΔT) analysis indicated that the addition of IL could significantly broaden ΔT of the PVA/IL composites, and their ΔT values first remained basically unchanged and then increased slightly with an increase of IL. In addition, MI analysis presented that the melt processability of the PVA/IL composites was not improved with the addition of IL and it was gradually improved with increasing IL content. In this work, PVA/IL composites with wide ΔT and high melt flow properties were prepared, which will lay a solid foundation for the preparation of high‐performance PVA fibers by melt spinning. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Hyperbranched poly (phenylalanine-lysine) (HBPL) is obtained by phenylalanine and lysine and then mixed with Polyvinyl Alcohol (PVA) polymer to electrospin PVA/HBPL fluorescent nanofiber mats (FNM), which is an excellent sensing material for Cu2+ ions in aqueous solutions. In this work, the relationship between mechanical properties, fluorescent properties and the sensing for Cu2+ ions of PVA/HBPL FNM are investigated. PVA/HBPL FNM with different mass ratio of PVA and HBPL are characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectra, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), fluorescence spectrum and tensile tester. To further improve the water solubility of PVA/HBPL FNM, thermally cross-linking (TCL)-PVA/HBPL FNM is fabricated. The results indicate that the neat PVA FNM couldn't emit fluorescence under any excitation wavelength, whereas the PVA/HBPL FNM emit blue fluorescence green fluorescence when the irradiation of the excitation wavelength is at 330–385 nm and 450–480 nm, respectively. The tensile strength and Young's modulus of PVA/HBPL FNM are 8.67 MPa and 342.92 MPa, respectively, which suggested 43.1% and 242.7% than that of neat PVA NM. Furthermore, the solubility rate of TCL-PVA/HBPL FNM is significantly decreased in comparison of FNM in absent of cross-linking. It's worth noting that TCL-PVA/HBPL FNM possessed higher recognition than other mental ions and could be used as metal ion detection sensor to combine with Cu2+. Moreover, it represented a linear relationship between the fluorescence intensity and the concentration of Cu2+ in the range of 5 µM to 100 µM. The fabricated TCL-PVA/HBPL FNM exhibit high mechanical and fluorescence properties, which make it be potentially envisaged for heavy metal ions detection sensor. [ABSTRACT FROM AUTHOR]

In order to significantly enhance the fluorescence and mechanical properties of polyvinyl alcohol (PVA) fluorescent fibers, HBP(P-L) is synthesized by lysine, phenylalanine and N,N-methylene bisacrylamide via Michael addition reaction. Acidified multiwalled carbon nanotubes (MWCNTs) are added in HBP(P-L) solution, which are sonicated to obtain MWCNTs-HBP(P-L). Moreover, MWCNTs-HBP(P-L) is incorporated with PVA polymer to fabricate PVA fluorescence fibers via wet spinning. The fluorescence and mechanical properties of fabricated PVA fluorescence fibers are characterized by SEM, FTIR, XRD, DSC, fibers tensile tester and fluorescence spectroscopy. The results display that the neat PVA fibers could not emit fluorescence when emission peak is at 450–480 nm, while MWCNTs-HBP(P-L)/PVA fibers could emit green fluorescence. The neat PVA fibers still could not emit fluorescence when emission peak is at 530–550 nm, while MWCNTs-HBP(P-L)/PVA fibers could emit dark red fluorescence. Furthermore, the crystallinity, the degree of orientation, the breaking strength and modulus of MWCNTs-HBP(P-L)/PVA fibers are 65.0%, 93.8%, 6.52 cN/dtex and 76.33 cN/dtex, respectively. Especially, the breaking strength and modulus of MWCNTs-HBP(P-L)/PVA fibers are 15.2% and 82.1% higher than that of neat PVA fibers. The fabricated MWCNTs-HBP(P-L)/PVA fibers exhibit unique mechanical and fluorescence properties, which make it be potentially envisaged in biomedical application. [ABSTRACT FROM AUTHOR]

In this study, we investigated engineered nanoparticle (ENP) release associated with the contamination of personal protective clothing during the simulated motion of the human wearing the ENP-contaminated protective clothing and evaluated the relative ENP retention on the fabric. The release of airborne ENPs can contribute to inhalation exposure, which is the route of exposure of most concern to cause adverse health effects in the pulmonary system. The evaluation focuses on four popular fabric materials making the laboratory coats (cotton, polypropylene, polyester cotton blend, and Tyvek) and three types of ENPs (Al2O3, carbon black (CB), and carbon nanotube (CNT)). The magnitudes of particle contamination and resuspension were investigated by measuring the number concentration increase of airborne particles in sizes of 10 nm to 10 μm and the weight changes on fabric pieces. Collected aerosol particles and contaminated fabric surfaces were further characterized for understanding particle morphology, elements, agglomeration, and surface contamination status. The particle resuspension from the contaminated lab coat fabric was found to vary by the type of fabric material. Cotton fabric showed the highest level of particle resuspension for all three tested ENPs. Data were evaluated to determine the dominant forces responsible for ENP adhesion on the surface of the fabric. Tyvek fabric was determined as the best fabric for trapping Al2O3 and carbon black ENPs, indicating less resuspension of particles, meaning lower subsequent release, but not durable enough to wear for the long term compared with other fabrics. [ABSTRACT FROM AUTHOR]

To improve the mechanical properties of polyvinyl alcohol (PVA) fibers, a series of PVA fibers were prepared via dry‐wet spinning with cross‐linking of boric acid (BA) (PVA/BA fibers), and using the mixed solvent of dimethyl sulfoxide and water. Moreover, the final PVA/BA fibers were characterized by Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), differential scanning calorimetery (DSC), thermogravimetric analyzer (TGA), powder X‐ray diffraction (XRD) and yarn strength tester. Furthermore, with the increasing of BA content, FTIR analysis showed that the degree of crosslinking of BA with PVA increased. SEM images of final PVA/BA fibers presented smooth surfaces, and the diameters decreased firstly and then increased. DSC, TGA, and XRD analysis indicated that the melting temperatures, thermal properties and crystallinities first increased and then decreased with the increasing of BA content. In addition, mechanical properties measurements illustrated that the cross‐linking existed at an optimal BA content of 0.3 wt%, and PVA/BA‐0.3 fiber had the highest tensile strength and Young's modulus of 13.1 ± 0.4 and 360.2 ± 10.4 cN/dtex, respectively. [ABSTRACT FROM AUTHOR]

Poly-lactic-co-glycolic acid (PLGA) was mixed with gentamicin sulfate via a double emulsion method, resulting in gentamicin-loaded PLGA nanoparticles that exhibited excellent antibacterial properties and great potential in fabricating smart wound dressings integrated with a drug delivery system. The nanoparticle morphologies, particle degradation rates, drug release profiles, and antibacterial properties were investigated using scanning electron microscopy (SEM), dynamic light scattering (DLS), ultraviolet–visible spectroscopy (UV–vis), and disk diffusion method. Nanoparticles prepared at different PLGA concentrations exhibited different release profiles that were determined by multiple release mechanisms including diffusion, osmotic pumping, and nanoparticle degradation. The antibacterial activities were measured using a disk diffusion method indicating that various nanoparticles loaded with antibiotics can control bacterial infection to some degree proving that nanoparticles used in this paper can be used in the pharmaceutical industry. The results suggested that drug release properties of gentamicin loaded PLGA nanoparticles can be affected by PLGA concentrations and PVA concentrations in the particle synthesis, providing a guidance in preparing gentamicin-loaded PLGA nanoparticles for topical antibiotics delivery applications. The nanoparticles with a spherical and uniformly porous structure were prepared with a PLGA concentration of 0.0167 g/ml and a PVA concentration of 12%, resulting in the highest average gentamicin release rate and excellent antibacterial activities. Four release mechanisms (diffusion through polymer, diffusion through pores, osmotic pumping, and nanoparticle degradation) primarily determined the gentamicin release process. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) fibers were prepared using PVA with different degree of polymerization (DP) under the same wet spinning process. The effect of the DP of PVA on the structures and properties of PVA and PVA fibers were studied by using nuclear magnetic resonance hydrogen spectroscopy (1H‐NMR), Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), differential scanning calorimeter (DSC), thermo gravimetric analysis (TGA), and environmental scanning electron microscope (ESEM). The results showed that DP had little effect on the crystallinity and tacticity of PVA, but had a positive effect on melting temperature, and initial decomposition temperature of PVAs. The hot drawing ratio determined by the spinning process where the PVA fibers could be continuously collected without breaking. The drawing ratio was decreased with an increase of DP, resulting in an increase of the final fiber diameter. The PVA fibers with medium DP and medium size demonstrated high strength and high modulus, but relatively low breaking elongation. It suggested that high DP of PVA was not a guarantee of high strength and high modulus PVA fibers, but rather a primary structure factor. The fiber performance was determined by a comprehensive effect combining a variety of factors including polymer properties and spinning conditions. It provided a guideline for PVA fiber manufacture that the PVAs with different DP require different spinning processes to obtain optimal fiber performance. [ABSTRACT FROM AUTHOR]

Biomaterials to facilitate the restoration of cardiac tissue is of emerging importance. While there are many aspects to consider in the design of biomaterials, mechanical properties can be of particular importance in this dynamically remodeling tissue. This review focuses on one specific processing method, electrospinning, that is employed to generate materials with a fibrous microstructure that can be combined with material properties to achieve the desired mechanical behavior. Current methods used to fabricate mechanically relevant micro-/nanofibrous scaffolds, in vivo studies using these scaffolds as therapeutics, and common techniques to characterize the mechanical properties of the scaffolds are covered. We also discuss the discrepancies in the reported elastic modulus for physiological and pathological myocardium in the literature, as well as the emerging area of in vitro mechanobiology studies to investigate the mechanical regulation in cardiac tissue engineering. Lastly, future perspectives and recommendations are offered in order to enhance the understanding of cardiac mechanobiology and foster therapeutic development in myocardial regenerative medicine. [ABSTRACT FROM AUTHOR]

ABSTRACT: Hyperbranched polymers have been found effective in controlling the dispersibility of carbon nanotubes in aqueous solutions. In this study, hyperbranched polylysine (HBPL) was synthesized using lysine and N,N′‐methylenebisacrylamide as precursors via Michael addition. The HBPL then was used to noncovalently modify multiwalled carbon nanotubes (MWCNTs) to prepare MWCNTs‐HBPL. The obtained MWCNTs‐HBPL composites were characterized using FTIR spectroscopy, Raman spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The results showed that the HBPL was successfully attached to the surface of MWCNTs via noncovalent interactions. The dispersibility of the MWCNTs‐HBPL composites in aqueous solutions was investigated using digital photographs, ultraviolet–visible absorption spectroscopy, and zeta potential measurements. The results demonstrated that both the mass ratio of MWCNT to HBPL and the pH of the solution had a significant impact on the dispersibility of the MWCNTs/HBPL solution, suggesting that HBPL treatment is an effective method of controlling the dispersibility of MWCNTs in aqueous solutions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46249. [ABSTRACT FROM AUTHOR]

Persimmon dye is a natural dye potentially used to promote sustainable textile industry. In this article, cotton and wool fabrics were dyed with persimmon dye. The performance of the dye was characterized using color strength and appearance analysis (ColorQuest), American Association of Textile Chemists and Colorists colorfastness tests, and Fourier transform infrared spectroscopy (FTIR). The results showed color strength of dyed cotton and wool fabrics was enhanced with increasing dye concentration and dyeing times. The comparison between cotton and wool suggested persimmon dye exhibits better dyeing performance (higher color strength and higher colorfastness ratings) on wool fabrics than on cotton fabrics. The FTIR analysis indicated no significant chemical reactions or changes in persimmon dye occurred to dyed fabrics, suggesting negligible impact on chemical and physical properties of the dyed fabrics. The reported results are valuable in exploring the opportunity of using persimmon dye as a useful natural dye for a sustainable textile dyeing industry, especially in the case of dyeing natural fibers. [ABSTRACT FROM AUTHOR]

10,12‐Pentacosadiynoic acid (PCDA) monomers were mixed with polyurethane (PU) or poly(ethylene oxide) (PEO) and the mixtures were electrospun to obtain composite nanofibers that were then photopolymerized via ultraviolet radiation, resulting polydiacetylene (PDA) in the nanofibers. The PDA demonstrated color‐changing properties in the presence of Escherichia coli, which exhibited potential for developing flexible colorimetric biosensors for medical textiles. Phase separation was found in the PEO–PDA fibers, resulting in amorphous PEO accumulation at the fiber surface. In contrast, the PU–PDA fibers demonstrated a homogeneous microstructure throughout the fibers. Tensile test results suggested a molecular orientation in the PU–PDA fibers that significantly improved the mechanical properties of the fibers. The presence of PDA in the matrix polymer reduced the overall strength and breaking elongation of both composite nanofibers in comparison to 100% PEO and PU fibers. A single PU–PDA fiber showed significantly higher stiffness and modulus than a single PEO–PDA fiber. Force–distance curve analysis suggested that the PU–PDA fibers exhibited an elastic deformation. In a comparison, the PEO–PDA fibers were brittle and showed low modulus. The results of structural and mechanical properties suggest that the PU–PDA nanofibers are a promising composite for developing nonadherent, durable, and flexible colorimetric biosensors used in medical textiles. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47877. [ABSTRACT FROM AUTHOR]