scholarly journals Evaluation of Nanocomposite Made of Polylactic Acid and Nanocellulose from Carrot Pomace Modified with Silver Nanoparticles

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 812 ◽  
Author(s):  
Monika Szymańska-Chargot ◽  
Monika Chylińska ◽  
Piotr M. Pieczywek ◽  
Anna Walkiewicz ◽  
Giorgia Pertile ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Mechanical Properties ◽  
Carbon Dioxide ◽  
Silver Nanoparticles ◽  
Polylactic Acid ◽  
Cellulose Nanofibrils ◽  
Antibacterial Properties ◽  
Young Modulus ◽  
Transmission Rates ◽  
Degradation Temperature

In this research, it was proposed to use carrot cellulose nanofibrils (CCNF) isolated from carrot pomace modified with silver nanoparticles (AgNPs) as a filler of polylactic acid (PLA) composites matrix. The new procedure was based on two steps: first, the preparation of nanocellulose modified with metal nanoparticles, and then the combination with PLA. Two concentrations—0.25 mM and 2 mM—of AgNO3 were used to modify CCNF. Then, PLA was mixed with the filler (CCNF/AgNPs) in two proportions 99:1 and 96:4. The influence of CCNF/AgNPs on mechanical, hydrophilic, thermal, and antibacterial properties of obtained nanocomposites was evaluated. The greatest improvement of mechanical properties was observed for composite containing CCNF with 2 mM of AgNPs, which obtained the lowest Young modulus and highest strain at break. The degradation temperature was lower for PLA with CCNF/AgNPs, but crystallization temperature wasn’t influenced. The addition of CCNF/AgNPs also increased hydrophilicity. The transmission rates of oxygen, nitrogen, and carbon dioxide also increased after the addition of CCNF/AgNPs to PLA. The antibacterial function against Escherichia coli and Bacillus cereus was obtained after the addition of AgNPs but only at the contact surface with the material made, suggesting the lack of migration of nanoparticles from the composite.

Preparation and study on the optical, mechanical, and antibacterial properties of polylactic acid/ZnO/TiO2 shared nanocomposites

2020 ◽  
Vol 36 (3) ◽  
pp. 285-311
Author(s):  
Ali Tajdari ◽  
Amir Babaei ◽  
Alireza Goudarzi ◽  
Razie Partovi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Antibacterial Activity ◽  
Optical Properties ◽  
Polylactic Acid ◽  
Field Emission ◽  
Antibacterial Properties ◽  
Hydrolytic Degradation ◽  
Scanning Electron

In this research, first, ZnO nanorods were synthesized by hydrothermal method and characterized in terms of morphological and structural properties by means of field emission scanning electron microscopy, Fourier transform infrared, and X-ray diffraction techniques. Subsequently, polylactic acid/ZnO, polylactic acid/TiO2, and polylactic acid/ZnO/TiO2 nanocomposites with different percentages of nanoparticles and two different types of ZnO morphologies were prepared and their microstructural, optical, mechanical, hydrolytic degradation, and antibacterial properties were investigated. Field emission scanning electron microscopy results of polylactic acid/ZnO and polylactic acid/TiO2 samples showed a proper dispersion and nanoparticle distribution for low percentages (up to 5 wt%) and increased aggregation for the higher percentages. Besides, a large increase in the aggregation tendency was observed for combined nanoparticles (polylactic acid/ZnO/TiO2 nanocomposites). Results of the tensile test, the UV–Vis absorption tests, and the hydrolytic degradation tests of the samples showed an enhanced mechanical (approximately 55% increase in the presence of 3–5 wt% of nanoparticles) and light absorption and degradation (approximately 85% increase in the presence of 3–10 wt% of nanoparticles) for the polylactic acid by incorporating nanoparticles. It was also observed that, in addition to the quality of dispersion and distribution of nanoparticles in the polymeric matrix, the type of morphology of nanoparticles can contribute to the improvement of these properties. The cylindrical morphology of ZnO played a greater role on improving the polylactic acid mechanical properties compared to the spherical ZnO morphology (approximately 20%). On the contrary, the increased polylactic acid optical properties and degradation with ZnO spherical morphology were more pronounced (approximately 60%). Interestingly, when both ZnO and TiO2 were added, a synergistic effect in the case of UV-shielding and degradation rate and alternatively, a detrimental effect on the mechanical properties were detected. (The polylactic acid optical properties increased by about 17% and its degradation more than doubled.) Furthermore, the antibacterial activity of polylactic acid was investigated against the two Gram-positive Listeria monocytogenes and Gram-negative bacteria Escherichia coli by incorporating nanoparticles. The results indicated that as the nanoparticle percentage increases, the antibacterial activity steadily increases.

scholarly journals Structure and Properties of Polylactic Acid Biocomposite Films Reinforced with Cellulose Nanofibrils

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3306
Author(s):  
Qianqian Wang ◽  
Chencheng Ji ◽  
Jianzhong Sun ◽  
Qianqian Zhu ◽  
Jun Liu
Keyword(s):  
Polylactic Acid ◽  
Cellulose Nanofibrils ◽  
Nitrogen Atmosphere ◽  
Scanning Calorimetry ◽  
Enzymatic Pretreatment ◽  
Thermogravimetric Analyzer ◽  
Degradation Temperature ◽  
Biocomposite Films ◽  
Renewable Feedstock ◽  
Vis Spectroscopy

Polylactic acid (PLA) is one of the most promising biodegradable and recyclable thermoplastic biopolymer derived from renewable feedstock. Nanocellulose reinforced PLA biocomposites have received increasing attention in academic and industrial communities. In the present study, cellulose nanofibrils (CNFs) was liberated by combined enzymatic pretreatment and high-pressure homogenization, and then subsequently incorporated into the PLA matrix to synthesize PLA/CNF biocomposite films via solution casting and melt compression. The prepared PLA/CNF biocomposite films were characterized in terms of transparency (UV-Vis spectroscopy), chemical structure (attenuated total reflectance-Fourier transform infrared, ATR-FTIR; X-ray powder diffraction, XRD), thermal (thermogravimetric analyzer, TGA; differential scanning calorimetry, DSC), and tensile properties. With 1.0–5.0 wt % additions of CNF to the PLA matrix, noticeable improvements in thermal and physical properties were observed for the resulting PLA/CNF biocomposites. The 2.5 wt % addition of CNF increased the tensile strength by 8.8%. The Tonset (initial degradation temperature) and Tmax (maximum degradation temperature) after adding 5.0 wt % CNF was increased by 20 °C, and 10 °C, respectively in the nitrogen atmosphere. These improvements were attributed to the good dispersibility and improved interfacial interaction of CNF in the PLA matrix.

scholarly journals Does the Antibacterial Activity of Silver Nanoparticles Depend on the Shape of the Nanoparticle? A Study of the Gram-Negative Bacterium Escherichia coli

2007 ◽  
Vol 73 (6) ◽  
pp. 1712-1720 ◽  
Author(s):  
Sukdeb Pal ◽  
Yu Kyung Tak ◽  
Joon Myong Song
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Antibacterial Properties ◽  
Negative Bacterium ◽  
Gram Negative ◽  
Energy Filtering ◽  
Transmission Electron ◽  
Triangular Silver Nanoplates ◽  
Liquid Systems ◽  
Biocidal Property

ABSTRACT In this work we investigated the antibacterial properties of differently shaped silver nanoparticles against the gram-negative bacterium Escherichia coli, both in liquid systems and on agar plates. Energy-filtering transmission electron microscopy images revealed considerable changes in the cell membranes upon treatment, resulting in cell death. Truncated triangular silver nanoplates with a {111} lattice plane as the basal plane displayed the strongest biocidal action, compared with spherical and rod-shaped nanoparticles and with Ag+ (in the form of AgNO3). It is proposed that nanoscale size and the presence of a {111} plane combine to promote this biocidal property. To our knowledge, this is the first comparative study on the bactericidal properties of silver nanoparticles of different shapes, and our results demonstrate that silver nanoparticles undergo a shape-dependent interaction with the gram-negative organism E. coli.

Antibacterial properties and cytocompatibility of bio-based nanostructured carbon aerogels derived from silver nanoparticles deposited onto bacterial cellulose

RSC Advances ◽  
2015 ◽  
Vol 5 (118) ◽  
pp. 97467-97476 ◽  
Author(s):  
Ning Yan ◽  
Yabin Zhou ◽  
Yudong Zheng ◽  
Shuang Qiao ◽  
Qun Yu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Silver Nanoparticles ◽  
Controlled Release ◽  
Bacterial Cellulose ◽  
Antibacterial Properties ◽  
Carbon Aerogels ◽  
Nanostructured Carbon

p-BC/AgNP carbon aerogels with excellent reabsorption capacities and mechanical properties were prepared by in situ reduction and carbonization. The aerogels had better antibacterial behavior and biocompatibility due to their slow controlled release of silver.

Polylactic Acid/Halloysite Nanotubes-Titanium Dioxide Nanocomposites: Antibacterial and Mechanical Properties

2021 ◽  
Vol 1021 ◽  
pp. 270-279
Author(s):  
Abdulkader M. Alakrach ◽  
Awad A. Al-Rashdi ◽  
Taha Alqadi ◽  
Mohammed Abdulhakim Al Saadi ◽  
Sam Sung Ting ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
High Efficiency ◽  
Antibacterial Effect ◽  
Control Sample ◽  
Antibacterial Properties ◽  
Halloysite Nanotubes ◽  
Solution Casting ◽  
Elapsed Time ◽  
Solution Casting Method

Polylactic acid (PLA) nanocomposite samples with different properties like mechanical, thermal, barrier and antibacterial properties are good candidates as packaging biomaterials. Unique PLA/TiO2 and PLA/HNTs-TiO2 nanocomposite samples were fabricated by solution casting method. The mechanical and antibacterial properties of PLA/TiO2 and PLA/HNTs-TiO2 samples were investigated with comparing to the pristine PLA film as a control sample. PLA nanocomposite samples with TiO2 nanofillers showed poorer mechanical properties while PLA films with PLA/HNTs-TiO2 showed unique developments, which tensile strength improved by 46% with the incorporation of 5 wt%. The PLA nanocomposites showed a high efficiency to both Gram positive and Gram negative bacteria, significant antibacterial effect being proved after first week elapsed time by comparing to the control sample (presenting no antibacterial effect). By considering the multifunctional characteristics of PLA/TiO2 and PLA/HNTs-TiO2 nanocomposites, the samples produced by solution casting can be considered a favourable alternative as environmental-friendly packaging materials.

scholarly journals Improvement of mechanical-antibacterial performances of AR/PMMA with TiO2 and HPQM treated by N-2(aminoethyl)-3-aminopropyl trimethoxysilane

2020 ◽  
pp. 073168442097519
Author(s):  
Paveena Tangudom ◽  
Ignacio Martín-Fabiani ◽  
Benjaphorn Prapagdee ◽  
Ekachai Wimolmala ◽  
Teerasak Markpin ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Mechanical Properties ◽  
Titanium Dioxide ◽  
Carboxylic Acid ◽  
Cell Growth ◽  
Antibacterial Property ◽  
Antibacterial Properties ◽  
Antibacterial Performance ◽  
Quinoline Carboxylic Acid ◽  
Antibacterial Material

The mechanical and antibacterial properties of acrylic rubber/poly(methyl methacrylate) (AR/PMMA) blend at 10 to 50 wt% of AR content with non-treated and treated titanium dioxide (TiO2) and 2-Hydroxypropyl-3-piperazinyl-quinoline carboxylic acid methacrylate (HPQM) by N-2(aminoethyl)-3-aminopropyl trimethoxysilane were studied. The antibacterial property against Escherichia coli was evaluated. The results found that the mechanical properties of ARt-TiO2/PMMA and ARt-HPQM/PMMA blend were higher than that of the ARTiO2/PMMA and ARHPQM/PMMA blend. For antibacterial property, the ARHPQM/PMMA and ARt-HPQM/PMMA blend could act as the antibacterial material, while the ARTiO2/PMMA blend did not show. However, the ARt-TiO2/PMMA blend could inhibit bacterial cell growth with 10 to 30 wt% of AR content. The recommended compositions of ARt-TiO2/PMMA blend, which improved both mechanical and antibacterial properties, were 10 to 30 wt% of AR and were 10 to 50 wt% of AR for ARt-HPQM/PMMA. Moreover, the UV radiation increased the antibacterial properties by the destruction of the interaction in treated TiO2 and HPQM and improved the antibacterial performance of ARt-TiO2/PMMA and ARt-HPQM/PMMA blend.

scholarly journals Influence of Different Pretreatments on the Antibacterial Properties of Chitosan Functionalized Viscose Fabric: TEMPO Oxidation and Coating with TEMPO Oxidized Cellulose Nanofibrils

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3144 ◽  
Author(s):  
Matea Korica ◽  
Zdenka Peršin ◽  
Snežana Trifunović ◽  
Katarina Mihajlovski ◽  
Tanja Nikolić ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Antibacterial Activity ◽  
Cellulose Nanofibrils ◽  
Antibacterial Properties ◽  
Value Added ◽  
Oxidized Cellulose ◽  
Tempo Oxidation ◽  
Medical Textiles ◽  
Washing Durability ◽  
Aldehyde Groups

The main objective of this study was to obtain chitosan functionalized viscose fabric with improved antibacterial properties and washing durability. In this regard carboxyl and aldehyde groups, as binding points for irreversible chitosan attachment into/onto viscose fabric, were introduced by two different pretreatments: 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) oxidation and coating with TEMPO oxidized cellulose nanofibrils (TOCN). The Fourier transform infrared spectroscopy, elemental analysis, zeta potential measurements, scanning electron microscopy, breaking strength and antibacterial testing were used to evaluate the influence of these pretreatments on chitosan binding, but also on chemical, electrokinetic, morphological, mechanical and antibacterial properties of pretreated and chitosan functionalized viscose fabrics. Washing durability of chitosan functionalized viscose was monitored through changes in the chitosan content, electrokinetic and antibacterial properties after multiple washing. TOCN coating improves mechanical properties of fabric, while TEMPO oxidation deteriorates them. The results show that both pretreatments improve chitosan adsorption and thus antibacterial properties, which are highly durable to washing. After five washings, the chitosan functionalized pretreated viscose fabrics preserve their antibacterial activity against Staphylococcus aureus, while antibacterial activity against Escherichia coli was lost. TOCN coated and chitosan functionalized viscose fabric is a high value-added product with simultaneously improved antibacterial and mechanical properties, which may find application as medical textiles.

scholarly journals Effects of Pulp Fiber and Epoxidized Tung Oil Content on the Properties of Biocomposites Based on Polylactic Acid

2020 ◽  
Vol 4 (2) ◽  
pp. 56 ◽  
Author(s):  
Van Khoi Nguyen ◽  
Thanh Tung Nguyen ◽  
Thu Ha Pham Thi ◽  
Thu Trang Pham
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
Fiber Composites ◽  
Pulp Fiber ◽  
Fiber Reinforced ◽  
Pulp Fibers ◽  
Plant Fibers ◽  
Tung Oil ◽  
Degradation Temperature ◽  
Internal Mixer

Recently, various environmental-friendly materials have been investigated and developed, especially composites of polylactic acid (PLA) and plant fibers. This paper investigates the effects of pulp fiber (PF) and epoxidized Tung oil (ETO) content on the properties of biocomposites, based on polylactic acid. The bleached pulp fiber reinforced PLA (PLA/PF) composites with 10–50 wt% fiber contents and 0–15% epoxidized Tung oil contents (with a certain number of fiber) were prepared in an internal mixer (Plastograph® EC) at 150 °C. The mechanical properties of PLA/PF composites were improved significantly. The pulp fiber reinforced PLA composites, with the fiber content of 30 wt%, were found to have the highest mechanical properties. The tensile and flexural properties of PLA/Tung oil-soaked-pulp fiber composites were higher than those of PLA/Tung oil unsoaked pulp fiber composites. In addition, the degradation temperature of PLA-based composites decreased after adding more pulp fiber. The pulp fibers were well-dispersed in the PLA matrix with the content up to 30 wt%. The interaction between pulp fiber and PLA matrix improved by the addition of epoxidized Tung oil. Epoxidized Tung oil also improved tensile and flexural strength of composite materials when it was added with a number of below 10% of fiber.

Novel Nanofibrous Scaffold to Improve Wound Healing

2013 ◽  
Author(s):  
Eva Yi-Wah Mak ◽  
Wallace Woon-Fong Leung
Keyword(s):  
Escherichia Coli ◽  
Mechanical Properties ◽  
Staphylococcus Aureus ◽  
Acidic Solution ◽  
Antibacterial Properties ◽  
Chitosan Solution ◽  
Skin Wound ◽  
Gram Negative ◽  
Native Skin ◽  
Improve Wound Healing

An antibacterial and biocompatible scaffold for fibroblasts proliferation based on chitosan has been developed. Chitosan solution is electrospun into uniform fibers of 100–200 nm in diameter that mimic the extracellular matrix of human skin. The fibrous mats are successfully cross-linked to be stable in acidic solution, which can be used to treat acute wounds. The crosslinked fibrous mats display antibacterial properties toward Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The mechanical properties of fibrous mats are shown to be comparable to native skin dermis which protects the skin wound.

Sign in / Sign up

Export Citation Format

Share Document