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Myricetin (Myr) is a naturally occurring flavonoid exhibiting diverse biological and pharmacological properties, but its characteristics such as water insolubility, poor aqueous stability, and poor bioavailability limit its clinical application, including in ophthalmology. To increase its clinical application in ophthalmology, Myr was designed to be encapsulated in a polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (PVCL-PVA-PEG) polymeric micelles to increases its aqueous solubility, stability, and corneal permeability to promote its efficacy in eye disease treatments. Thus, the Myr micelle ophthalmic solution was prepared and characterized encapsulation efficiency (EE), micelle size, and zeta potential. The chemical stability of Myr and the short-term storage stability of the Myr micelle ophthalmic solution were evaluated, followed by in vitro cytotoxicity and in vivo ocular irritation; in vitro cellular uptake and in vivo corneal permeation; and in vitro antioxidant activity and in vivo anti-inflammatory efficacy were also further evaluated. Myr could be incorporated into micelles with high EE. PVCL-PVA-PEG micelles significantly enhanced Myr's aqueous solubility and chemical stability. The Myr micelle ophthalmic solution also showed high storage stability. In rabbits, the Myr micelle ophthalmic solution displayed good in vitro cellular tolerance. Remarkable improvements in in vitro cellular uptake and in vivo corneal permeation were also observed in the Myr micelle ophthalmic solution, and significant improvements in the in vitro antioxidant activity and in vivo anti-inflammatory efficacy were also obtained. Overall, these results supported that the Myr micelle ophthalmic solution could be a promising nanomedicine for ocular tissues.

This study deals with the scanning electron microscopy (SEM) analyses of the phase interfaces in the glued joints between Norway spruce wood elements thermally modified at 160, 180, 200, and 220 °C/4 h and polyurethane (PUR) and polyvinyl acetate (PVAc) glues with the aim of evaluating various anatomical influences of wood on the quality of joints. Due to cracked regions created in the surface of spruce wood at severe thermal modifications, the penetration depth of glues doubled from 140 to 241 μm for PUR glue, and from 100 to 200 μm for PVAc glue. The thickness of glue lines in joints was apparently higher for PVAc glue, mainly in earlywood regions; however, in joints from thermally modified (TM) woods it increased more apparently for PUR glue from 16.6 to 44.4 μm, probably in connection with formation of micro-bubbles in its structure. The SEM analyses corresponded well with the previous knowledge about lower shear strength of glued joints formed from the more intensively TM spruce elements and mentioned types of glues.

Chitosan Schiff base/polyvinyl acetate (CSB/PVAc) and its Fe2O3 (CSB/PVAc@Fe2O3) nanocomposite were fabricated and characterized using different techniques, including FT-IR, XRD, SEM/EDS, BET, TGA, and DSC. They were used as suitable adsorbents for removing eosin yellow (EY), and Fluorescein (FS) dyes from the aqueous solution. The adsorption experiments were optimized by varying the essential parameters: pH solution, adsorbent dose, and contact time. Under optimum conditions (pH = 3 and 0.02 g dose of sorbents), the maximum removal efficiency was 75.65% and 95.53% for EY and 80.51% and 93.46% for FS using CSB/PVAc and CSB/PVAc@Fe2O3, respectively. Kinetic studies used pseudo-first-order, pseudo-second-order, and intra-particle diffusion models. The experimental data obeyed the intra-particle diffusion model. The adsorption data were analyzed using the Langmuir and Freundlich isotherms. According to the results, the experimental data fitted well with the Freundlich model as a heterogenous process. Finally, the removal efficiency of the new adsorbet CSB/PVAc@Fe2O3 become less active (< 7%) towards EY and FS dyes after 5 runs.

Since their development in the 1950s, poly(vinyl acetate) [PVAc] paints (also known as vinyl) have been used by many artists, most notably in countries such as Spain, Portugal, and the United Kingdom; they are also used globally as a common binder for house paints. However, only a relatively limited number of heritage scientific studies have focused on vinyl paints. Consequently, many critical aspects of this material, such as the degradation processes, variations in paint formulations, and responses to conservation treatments, remain largely understudied. This article aims to summarise the available relevant information on poly(vinyl acetate) paints from both the scientific and the conservation practice perspectives. The article provides a brief overview of the development of poly(vinyl acetate) paints as artist-grade and household products and the known differences in their formulations. It also focuses on poly(vinyl acetate) ageing behaviour, the physicochemical properties, the recent scientific research on poly(vinyl acetate) material characterisation and degradation, and the main conservation issues regarding these paints, such as those relating to cleaning treatments.

Adhesive modification with nanoparticles affects multiple adhesives properties, making it essential to evaluate and compare changes across all key characteristics—existing positive and limiting properties. This study investigates the impact of silica (SiO2) and titanium dioxide (TiO2) nanoparticles on the elasticity and aging resistance of PVAc adhesive. Tensile properties were determined according to ISO 527-3:2018, with Young’s moduli of elasticity Ε, and stress–strain curves for neat PVAc, nano-SiO2 PVAc, and nano-TiO2 PVAc adhesive. Material toughness (UT), failure stresses σf, and failure strains εf were also calculated. After UV exposure (0, 48, and 96 h), according to ISO 9142:2003, samples were characterized by Fourier-transform infrared spectroscopy (FTIR). Analysis of variance (ANOVA) was performed to determine if there is a statistically significant difference in material toughness between neat PVAc and nano-modified PVAc adhesives, as well as changes in FTIR spectra of paper–adhesive samples before and after UV exposure. The Bonferroni post hoc test was used to identify specific group differences. The results showed that SiO2 nanoparticles improved PVAc elasticity by 9.15%, while TiO2 nanoparticles reduced elasticity by 44.47%. FTIR analysis revealed similar behavior in both nano-modified and neat PVAc adhesives after UV exposure, indicating that aging resistance was preserved with the addition of SiO2 or TiO2.

The enzymatically induced carbonate precipitation (EICP) technique is currently studied for dust control because of the formation of cemented crust layer. In the present study, polyvinyl acetate (PVAc) was used with EICP together as the EICP-PVAc treatment to solidify dust soils. In addition, several treated dust soil areas always experience repeated freeze–thaw (FT) or dry–wet (DW) cycles, both of which result in the damage of structure. Therefore, the FT cycle test and the DW cycle test were conducted to study the durability of EICP-PVAc treatment. Results showed that both FT cycles and DW cycles affected the EICP-PVAc-treated dust soils. The wind-erosion resistance and rainfall-erosion resistance were impaired, and the surface strength decreased. However, the decreasing range resulted from the FT cycle was smaller than the decreasing range resulted from the DW cycle. It indicated the EICP-PVAc-treated dust soils had better FT durability, but the DW durability was worse. Moreover, a field test was used to study the durability of application of EICP-PVAc treatment in practical field test site. Based on the surface pattern observation after 9 months, the grasses in the treated area are in good growth condition; however, few grasses grew in the untreated area. The field test demonstrated that the combined EICP-PVAc and grass seeds treatment can ensure the long-term solidification effect and durability. The results lay a solid foundation for the applications of EICP-PVAc treatment to solidify dust soils for dust control.

This study presents the analysis of seven microsamples from Untitled Mural 3 , painted by David Alfaro Siqueiros between 1964 and 1972. The mural has never been restored, therefore preserving the materials used by the artist. The microsamples were analyzed using a combination of techniques: optical microscopy (OM), scanning electron microscopy with energy-dispersive spectroscopy (SEM–EDS), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), micro-Fourier transform infrared spectroscopy (micro-FTIR) with reflection mode, and high-resolution nuclear magnetic resonance (NMR) spectroscopy. In this work, compounds common to those identified in the analysis of the contemporary mural Trazos de composición piramidal composition were identified, such as acrylic and nitrocellulose binders, titanium white and iron red oxide as pigments, and DEHP as a plasticizer. Unexpectedly, polyvinyl acetate (PVAc) and different nitrocellulose monomers were identified, in addition to chrome yellow instead of ochre, and a predominance of quartz, asbestos, and talc as fillers, instead of carbonates. The study confirmed that Siqueiros used multiple binders in successive layers in no apparent order, providing valuable insights into his artistic techniques. The research also proved an efficient methodology for studying very small and complex samples.

This study explores the fabrication, structural characteristics, and performance of an innovative porous geopolymer membrane made from waste natural zeolite powder for Pb(II) removal, with potential applications in wastewater treatment. A hybrid geopolymer membrane incorporating polyvinyl acetate (PVAc) (10, 20, and 30 wt.%) was synthesized and thermally treated at 300 °C to achieve a controlled porous architecture. Characterization techniques, including Fourier-transform infrared spectroscopy (FTIR), revealed the disappearance of characteristic C=O and C-H stretching bands (~1730 cm−1 and ~2900 cm−1, respectively), confirming the full degradation of PVAc. Thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) indicated a total mass loss of approximately 14.5% for the sample with PVAc 20 wt.%, corresponding to PVAc decomposition and water loss. Energy-dispersive spectroscopy (EDS) elemental mapping showed the absence of carbon residues post-annealing, further validating complete PVAc removal. X-ray diffraction (XRD) provided insight into the crystalline phases of the raw zeolite and geopolymer structure. Once PVAc removal was confirmed, the second phase of characterization assessed the membrane’s mechanical properties and filtration performance. The thermally treated membrane, with a thickness of 2.27 mm, exhibited enhanced mechanical properties, measured with a nano-indenter, showing a hardness of 1.8 GPa and an elastic modulus of 46.7 GPa, indicating improved structural integrity. Scanning electron microscopy (SEM) revealed a well-defined porous network. Filtration performance was evaluated using a laboratory-scale dead-end setup for Pb(II) removal. The optimal PVAc concentration was determined to be 20 wt.%, resulting in a permeation rate of 78.5 L/(m2·h) and an 87% rejection rate at an initial Pb(II) concentration of 50 ppm. With increasing Pb(II) concentrations, the flux rates declined across all membranes, while maximum rejection was achieved at 200 ppm. FTIR and EDS analyses confirmed Pb(II) adsorption onto the zeolite-based geopolymer matrix, with elemental mapping showing a uniform Pb(II) distribution across the membrane surface. The next step is to evaluate the membrane’s performance in a multi-cation water treatment environment, assessing the sorption kinetics and its selectivity and efficiency in removing various heavy metal contaminants from complex wastewater systems.

Repercussion of overutilizing the fossil fuels and petrochemicals resulted in global warming and polluted environment. Hence, in the quest for alternative sources of raw materials for developing greener adhesives, renewable and natural polymers like polysaccharides have a huge potential. In particular, the traditional water-based emulsion wood adhesive employs colloid-like polyvinyl alcohol for stabilizing polyvinyl acetate (PVAc) emulsion. Researchers have recently become interested in utilizing xanthan gum, a naturally occurring polymer, in place of stabilizers. Here, the effects of xanthan gum addition as a stabilizer for PVAc homopolymer-based wood adhesives on performance properties were investigated. Emulsion polymerization technique was employed to synthesize xanthan gum stabilized PVAc homopolymer emulsion. Hence, the present work investigates the applicability of xanthan gum added 0.5% and 1% as a colloid for the synthesis of PVAc wood adhesives. Effect of the addition of xanthan gum as a colloid on physical, thermal, and mechanical properties was studied by viscosity, pH, contact angle measurement, differential scanning calorimetry (DSC), and pencil hardness test of films. Emulsions in varying xanthan gum concentrations were prepared, and a universal tensile machine was utilized to measure the shear strength of the PVAc homopolymers applied to wood. As the concentration of xanthan gum increased, the adhesives’ viscosity increased. The drastic increase in water resistance with increasing xanthan gum content was confirmed by water contact angle measurement. The use of xanthan gum improved the PVAc films’ hardness as well. When compared to a pristine sample, the tensile shear strength with 1 wt% of xanthan increased by 50% after 6 h of bonding in dry environment and by 61% in wet conditions (as per EN 204). The study’s overall conclusion highlights the enhanced adhesive performance of xanthan gum stabilized PVAc emulsion-based adhesives.

Here, the idea is to synthesize polyvinyl acetate (PVAc)/waterborne polyurethane-based (WPU) hybrid IPN network. The polyvinyl acetate emulsion (PVAc) and vinyl acetate/water-based polyurethane hybrid emulsions were successfully prepared in this research work. The weight percentage of polyurethane components was varied to synthesize emulsions with different properties. Two distinctly designed emulsion’s properties were studied using different characterization techniques such as dynamic light scattering (DLS), gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), nuclei magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical and thermal analysis (DMTA) to evaluate emulsion properties. The properties of PVAc and hybrid emulsions were checked, and their relative average molecular weights were determined by GPC. Also, their particle size distribution and zeta potential were performed to analyze the hybrid emulsion’s average volume distribution and stability. Thermomechanical and mechanical properties such as damping factor, storage modulus, loss modulus, tensile strength, and lap shear strength were correlated with the loading of WPU in PVAc emulsion to form a physical crosslinked network. The result showed a minimal change in the thermal response of hybrid emulsion properties but an improvement in lap shear strength was observed in hybrid emulsion compared with PVAc emulsion. Graphical abstract