Role of the chemical modification of titanium dioxide surface on the interaction with silver nanoparticles and the capability to enhance antimicrobial properties of poly(lactic acid) composites

Author(s):  
M. G. Peña-Juárez ◽  
M. Robles-Martínez ◽  
K. B. Méndez-Rodríguez ◽  
R. López-Esparza ◽  
Elías Pérez ◽  
...  
Molecules ◽  
2017 ◽  
Vol 22 (7) ◽  
pp. 1170 ◽  
Author(s):  
Wenhui Li ◽  
Cheng Zhang ◽  
Hai Chi ◽  
Lin Li ◽  
Tianqing Lan ◽  
...  

2021 ◽  
Vol 22 (6) ◽  
pp. 3150
Author(s):  
Anna Masek ◽  
Stefan Cichosz ◽  
Małgorzata Piotrowska

The study aimed to prepare sustainable and degradable elastic blends of epoxidized natural rubber (ENR) with poly(lactic acid) (PLA) that were reinforced with flax fiber (FF) and montmorillonite (MMT), simultaneously filling the gap in the literature regarding the PLA-containing polymer blends filled with natural additives. The performed study reveals that FF incorporation into ENR/PLA blend may cause a significant improvement in tensile strength from (10 ± 1) MPa for the reference material to (19 ± 2) MPa for the fibers-filled blend. Additionally, it was found that MMT employment in the role of the filler might contribute to ENR/PLA plasticization and considerably promote the blend elongation up to 600%. This proves the successful creation of the unique and eco-friendly PLA-containing polymer blend exhibiting high elasticity. Moreover, thanks to the performed accelerated thermo-oxidative and ultraviolet (UV) aging, it was established that MMT incorporation may delay the degradation of ENR/PLA blends under the abovementioned conditions. Additionally, mold tests revealed that plant-derived fiber addition might highly enhance the ENR/PLA blend’s biodeterioration potential enabling faster and more efficient growth of microorganisms. Therefore, materials presented in this research may become competitive and eco-friendly alternatives to commonly utilized petro-based polymeric products.


2021 ◽  
pp. 088532822110464
Author(s):  
Alexandre F Júnior ◽  
Charlene A Ribeiro ◽  
Maria E Leyva ◽  
Paulo S Marques ◽  
Carlos R J Soares ◽  
...  

The aim of this work was to study the biophysical properties of the chitosan-grafted poly(lactic acid) (CH-g-PLA) nanofibers loaded with silver nanoparticles (AgNPs) and chondroitin-4-sulfate (C4S). The electrospun CH-g-PLA:AgNP:C4S nanofibers were manufactured using the electrospinning technique. The microstructure of the CH-g-PLA:AgNP:C4S nanofibers was investigated by proton nuclear magnetic resonance (1H-NMR), scanning electron microscopy (SEM), UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), and Fourier transform infrared (ATR-FTIR) spectroscopy. ATR-FTIR and 1H-NMR confirm the CH grafting successfully by PLA with a substitution degree of 33.4%. The SEM measurement results indicated apparently smooth nanofibers having a diameter range of 340 ± 18 nm with porosity of 89 ± 3.08% and an average pore area of 0.27 μm2. UV-Vis and XRD suggest that silver nanoparticles with the size distribution of 30 nm were successfully incorporated into the electrospun nanofibers. The water contact angle of 12.8 ± 2.7° reveals the hydrophilic nature of the CH-g-PLA:AgNP:C4S nanofibers has been improved by C4S. The electrospun CH-g-PLA:AgNP:C4S nanofibers are found to release ions Ag+ at a concentration level capable of rendering an antimicrobial efficacy. Gram-positive bacteria ( S.aureus) were more sensitive to CH-g-PLA:AgNP:C4S than Gram-negative bacteria ( E. coli). The electrospun CH-g-PLA:AgNP:C4S nanofibers exhibited no cytotoxicity to the L-929 fibroblast cells, suggesting cytocompatibility. Fluorescence microscopy demonstrated that C4S promotes the adhesion and proliferation of fibroblast cells onto electrospun CH-g-PLA:AgNP:C4S nanofibers.


Author(s):  
Teresa C. O. Marsi ◽  
Ritchelli Ricci ◽  
Tatiane V. Toniato ◽  
Luana M. R. Vasconcellos ◽  
Conceição de Maria Vaz Elias ◽  
...  

2020 ◽  
Vol 31 (5) ◽  
pp. 1077-1087 ◽  
Author(s):  
Caixia Zhao ◽  
Miaomiao Yu ◽  
Qicheng Fan ◽  
Guoxiang Zou ◽  
Jinchun Li

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1878
Author(s):  
Marina Ramos ◽  
Elena Fortunati ◽  
Ana Beltrán ◽  
Mercedes Peltzer ◽  
Francesco Cristofaro ◽  
...  

Nano-biocomposite films based on poly (lactic acid) (PLA) were prepared by adding thymol (8 wt.%) and a commercial montmorillonite (D43B) at different concentrations (2.5 and 5 wt.%). The antioxidant, antimicrobial, and disintegration properties of all films were determined. A kinetic study was carried out to evaluate the thymol release from the polymer matrix into ethanol 10% (v/v) as food simulant. The nanostructured networks formed in binary and ternary systems were of interest in controlling the release of thymol into the food simulant. The results indicated that the diffusion of thymol through the PLA matrix was influenced by the presence of the nanoclay. Disintegration tests demonstrated that the incorporation of both additives promoted the breakdown of the polymer matrix due to the presence of the reactive hydroxyl group in the thymol structure and ammonium groups in D43B. Active films containing thymol and D43B efficiently enhanced the antioxidant activity (inhibition values higher than 77%) of the nano-biocomposites. Finally, the addition of 8 wt.% thymol and 2.5 wt.% D43B significantly increased the antibacterial activity against Escherichia coli and Staphylococcus aureus 8325-4, resulting in a clear advantage to improve the shelf-life of perishable packaged food.


2020 ◽  
pp. 096739112093135
Author(s):  
Mohammad Mahdi Salehi ◽  
Fatemeh Hakkak

The main objective of the present work was to study the role of carbon nanotube (CNT) on the microstructure development and physical, mechanical, and rheological properties of poly(lactic acid) (PLA)/natural rubber (NR)/CNT hybrid nanocomposites. The PLA/NR blend samples with constant blend ratio (90/10) were prepared by melt mixing in a laboratory internal mixer at a temperature of 190°C. The behavior of the PLA/NR blend was examined depending on the CNT content (0.5–6 wt%). The droplet size and droplet size distribution of the NR phase decreases with the increase in CNTs content. This could be explained in terms of compatibilizing effect of CNT and the changing of the viscosity ratio of the blend phases. The development of the microstructure and the physical properties of the blend were also investigated according to the CNT contents by measuring the linear viscoelasticity. The elongational behavior and mechanical properties of the blends were strongly dependent on the location of the CNT. The CNT worked as an efficient compatibilizer and also it worked as a reinforcing filler making the matrix more rigid.


Nanomaterials ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 22 ◽  
Author(s):  
Agueda Sonseca ◽  
Salim Madani ◽  
Gema Rodríguez ◽  
Víctor Hevilla ◽  
Coro Echeverría ◽  
...  

Poly(lactic acid) (PLA) is one of the most commonly employed synthetic biopolymers for facing plastic waste problems. Despite its numerous strengths, its inherent brittleness, low toughness, and thermal stability, as well as a relatively slow crystallization rate represent some limiting properties when packaging is its final intended application. In the present work, silver nanoparticles obtained from a facile and green synthesis method, mediated with chitosan as a reducing and stabilizing agent, have been introduced in the oligomeric lactic acid (OLA) plasticized PLA in order to obtain nanocomposites with enhanced properties to find potential application as antibacterial food packaging materials. In this way, the green character of the matrix and plasticizer was preserved by using an eco-friendly synthesis protocol of the nanofiller. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) results proved the modification of the crystalline structure as well as the crystallinity of the pristine matrix when chitosan mediated silver nanoparticles (AgCH-NPs) were present. The final effect over the thermal stability, mechanical properties, degradation under composting conditions, and antimicrobial behavior when AgCH-NPs were added to the neat plasticized PLA matrix was also investigated. The obtained results revealed interesting properties of the final nanocomposites to be applied as materials for the targeted application.


Sign in / Sign up

Export Citation Format

Share Document