Bottom-Up Development of Nanoimprinted PLLA Composite Films with Enhanced Antibacterial Properties for Smart Packaging Applications

In this work, polymer nanocomposite films based on poly(L-lactic acid) (PLLA) were reinforced with mesoporous silica nanoparticles, mesoporous cellular foam (MCF) and Santa Barbara amorphous-15 (SBA). PLLA is a biobased aliphatic polyester, that possesses excellent thermomechanical properties, and has already been commercialized for packaging applications. The aim was to utilize nanoparticles that have already been established as nanocarriers to enhance the mechanical and thermal properties of PLLA. Since the introduction of antibacterial properties has become an emerging trend in packaging applications, to achieve an effective antimicrobial activity, micro/nano 3D micropillars decorated with cone- and needle-shaped nanostructures were implemented on the surface of the films by means of thermal nanoimprint lithography (t-NIL), a novel and feasible fabrication technique with multiple industrial applications. The materials were characterized regarding their composition and crystallinity using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), respectively, and their thermal properties using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Their mechanical properties were examined by the nanoindentation technique, while the films’ antimicrobial activity against the bacteria Escherichia coli and Staphylococcus aureus strains was tested in vitro. The results demonstrated the successful production of nanocomposite PLLA films, which exhibited improved mechanical and thermal properties compared to the pristine material, as well as notable antibacterial activity, setting new groundwork for the potential development of biobased smart packaging materials.

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Starch–PVA Nanocomposite Film Incorporated with Cellulose Nanocrystals and MMT: A Comparative Study

International Journal of Food Engineering ◽

10.1515/ijfe-2015-0145 ◽

2016 ◽

Vol 12 (1) ◽

pp. 37-48 ◽

Cited By ~ 40

Author(s):

Nooshin Noshirvani ◽

Babak Ghanbarzadeh ◽

Hadi Fasihi ◽

Hadi Almasi

Keyword(s):

Thermal Properties ◽

Food Packaging ◽

Moisture Sorption ◽

Water Vapor Permeability ◽

Nanocrystalline Cellulose ◽

Nanocomposite Films ◽

Vapor Permeability ◽

Mechanical And Thermal Properties ◽

X Ray Diffraction ◽

Scanning Calorimetry

Abstract The goal of this work was to compare the barrier, mechanical, and thermal properties of two types of starch–polyvinyl alcohol (PVA) nanocomposites. Sodium montmorillonite (MMT) and nanocrystalline cellulose were chosen as nanoreinforcements. X-ray diffraction (XRD) test showed well-distributed MMT in the starch–PVA matrix, possibly implying that the clay nanolayers formed an exfoliated structure. The moisture sorption, solubility and water vapor permeability (WVP) studies revealed that the addition of MMT and nanocrystalline cellulose reduced the moisture affinity of starch–PVA biocomposite. At the level of 7 % MMT, the nanocomposite films showed the highest ultimate tensile strength (UTS) (4.93 MPa) and the lowest strain to break (SB) (57.65 %). The differential scanning calorimetry (DSC) results showed an improvement in thermal properties for the starch–PVA–MMT nanocomposites, but not for the starch–PVA–NCC nanocomposites. Results of this study demonstrated that the use of MMT in the fabrication of starch–PVA nanocomposites is more favorable than that of nanocrystalline cellulose to produce a desirable biodegradable film for food packaging applications.

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Mechanical and thermal characterization of grafted PP-NCC nanocomposites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705719878226 ◽

2019 ◽

pp. 089270571987822

Author(s):

Saud Aldajah ◽

Mohammad Y Al-Haik ◽

Waseem Siddique ◽

Mohammad M Kabir ◽

Yousef Haik

Keyword(s):

Thermal Properties ◽

Interfacial Adhesion ◽

Thermal Characterization ◽

Mechanical And Thermal Properties ◽

Screw Extruder ◽

Scanning Calorimetry ◽

Three Point Bending ◽

Twin Screw ◽

Thermal Stability Of

This study reveals the enhancement of mechanical and thermal properties of maleic anhydride-grafted polypropylene (PP- g-MA) with the addition of nanocrystalline cellulose (NCC). A nanocomposite was manufactured by blending various percentages of PP, MA, and NCC nanoparticles by means of a twin-screw extruder. The influence of varying the percentages of NCC on the mechanical and thermal behavior of the nanocomposite was studied by performing three-point bending, nanoindentation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy tests. The novelty of this study stems on the NCC nanoparticles and their ability to enhance the mechanical and thermal properties of PP. Three-point bending and nanoindentation tests revealed improvement in the mechanical properties in terms of strength, modulus, and hardness of the PP- g-MA nanocomposites as the addition of NCC increased. SEM showed homogeneity between the mixtures which proved the presence of interfacial adhesion between the PP- g-MA incorporated with NCC nanoparticles that was confirmed by the FTIR results. DSC and TGA measurements showed that the thermal stability of the nanocomposites was not compromised due to the addition of the coupling agent and reinforced nanoparticles.

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Chemistry of collagen cross-links: glucose-mediated covalent cross-linking of type-IV collagen in lens capsules

Biochemical Journal ◽

10.1042/bj2960489 ◽

1993 ◽

Vol 296 (2) ◽

pp. 489-496 ◽

Cited By ~ 73

Author(s):

A J Bailey ◽

T J Sims ◽

N C Avery ◽

C A Miles

Keyword(s):

Type Iv Collagen ◽

Cross Linking ◽

Mechanical And Thermal Properties ◽

Maximum Strain ◽

Scanning Calorimetry ◽

Melting Temperatures ◽

Type Iv ◽

Collagen Molecules ◽

Cross Links

The incubation of lens capsules with glucose in vitro resulted in changes in the mechanical and thermal properties of type-IV collagen consistent with increased cross-linking. Differential scanning calorimetry (d.s.c.) of fresh lens capsules showed two major peaks at melting temperatures Tm 1 and Tm 2 at approx. 54 degrees C and 90 degrees C, which can be attributed to the denaturation of the triple helix and 7S domains respectively. Glycosylation of lens capsules in vitro for 24 weeks caused an increase in Tm 1 from 54 degrees C to 61 degrees C, while non-glycosylated, control incubated capsules increased to a Tm 1 of 57 degrees C. The higher temperature required to denature the type-IV collagen after incubation in vitro suggested increased intermolecular cross-linking. Glycosylated lens capsules were more brittle than fresh samples, breaking at a maximum strain of 36.8 +/- 1.8% compared with 75.6 +/- 6.3% for the fresh samples. The stress at maximum strain (or ‘strength’) was dramatically reduced from 12.0 to 4.7 N.mm.mg-1 after glycosylation in vitro. The increased constraints within the system leading to loss of strength and increased brittleness suggested not only the presence of more cross-links but a difference in the location of these cross-links compared with the natural lysyl-aldehyde-derived cross-links. The chemical nature of the fluorescent glucose-derived cross-link following glycosylation was determined as pentosidine, at a concentration of 1 pentosidine molecule per 600 collagen molecules after 24 weeks incubation. Pentosidine was also determined in the lens capsules obtained from uncontrolled diabetics at a level of about 1 per 100 collagen molecules. The concentration of these pentosidine cross-links is far too small to account for the observed changes in the thermal and mechanical properties following incubation in vitro, clearly indicating that another as yet undefined, but apparently more important cross-linking mechanism mediated by glucose is taking place.

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The influence of adding long basalt fiber on the mechanical and thermal properties of composites based on poly(oxymethylene)

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718806549 ◽

2018 ◽

Vol 33 (4) ◽

pp. 435-450 ◽

Cited By ~ 4

Author(s):

Patrycja Bazan ◽

Stanisław Kuciel ◽

Mariola Sądej

Keyword(s):

Mechanical Properties ◽

Thermal Properties ◽

Average Length ◽

Flexural Modulus ◽

Basalt Fiber ◽

Charpy Impact ◽

Mechanical And Thermal Properties ◽

Gravimetric Analysis ◽

Scanning Calorimetry ◽

Atr Spectroscopy

The work has evaluated the possibility of the potential reinforcing of poly(oxymethylene) (POM) by basalt fibers (BFs) and influence of BFs addition on thermal properties. Two types of composites were produced by injection molding. There were 20 and 40 wt% long BFs content with an average length of 1 mm. The samples were made without using a compatibilizer. In the experimental part, the basic mechanical properties (tensile strength, modulus of elasticity, strain at break, flexural modulus, flexural strength, and deflection at 3.5% strain) of composites based on POM were determined. Tensile properties were also evaluated at three temperatures −20°C, 20°C, and 80°C. The density and Charpy impact of the produced composites were also examined. The influence of water absorption on mechanical properties was investigated. Thermal properties were conducted by the differential scanning calorimetry, thermal gravimetric analysis, and fourier transform infrared (FTIR)-attenuation total reflection (ATR) spectroscopy analysis. In order to make reference to the effects of reinforcement and determine the structure characteristics, scanning electron microscopy images were taken. The addition of 20 and 40 wt% by weight of fibers increases the strength and the stiffness of such composites by more than 30–70% in the range scale of temperature. Manufactured composites show higher thermal and dimensional stability in relation to neat POM.

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Evaluating the Antimicrobial Activity of Commercially Available Herbal Toothpastes on Microorganisms Associated with Diabetes Mellitus

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1427 ◽

2013 ◽

Vol 14 (5) ◽

pp. 924-929 ◽

Cited By ~ 4

Author(s):

Reena Kulshrestha ◽

J Kranthi ◽

P Krishna Rao ◽

Feroz Jenner ◽

V Abdul Jaleel ◽

...

Keyword(s):

Diabetes Mellitus ◽

Antimicrobial Activity ◽

Dental Health ◽

Antibacterial Properties ◽

Antimicrobial Properties ◽

Test Organism ◽

Diffusion Method ◽

Zone Of Inhibition ◽

Disk Diffusion Method

ABSTRACT Aim The present study was conducted to evaluate the efficacy of commercially available herbal toothpastes against the different periodontopathogens. Materials and methods Six herbal toothpastes that were commonly commercially available were included in the study. Colgate herbal, Babool, Meswak, Neem active, Dabur red toothpastes were tested for the study whereas sterile normal saline was used as control. Antimicrobial efficacies of dentifrices were evaluated against Streptococcus mutans and Actinobacillus actinomycetemcomitans. The antimicrobial properties of dentifrices were tested by measuring the maximum zone of inhibition at 24 hours on the Mueller Hinton Agar media inoculated with microbial strain using disk diffusion method. Each dentifrice was tested at 100% concentration (full strength). Results The study showed that all dentifrices selected for the study were effective against the entire test organism but to varying degree. Neem active tooth paste gave a reading of 25.4 mm as the zone of inhibition which was highest amongst all of the test dentifrices. Colgate Herbal and Meswak dentifrices recorded a larger maximum zone of inhibition, measuring 23 and 22.6 mm respectively, compared to other toothpastes. All other dentifrices showed the zone of inhibition to be between 17 and 19 mm respectively. Conclusion The antibacterial properties of six dentifrices were studied in vitro and concluded that almost all of the dentifrices available commercially had antibacterial properties to some extent to benefit dental health or antiplaque action. How to cite this article Jenner F, Jaleel VA, Kulshrestha R, Maheswar G, Rao PK, Kranthi J. Evaluating the Antimicrobial Activity of Commercially Available Herbal Toothpastes on Microorganisms Associated with Diabetes Mellitus. J Contemp Dent Pract 2013;14(5):924-929.

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Effects of Mullite, Maghemite, and Silver Nanoparticles Incorporated in β-Wollastonite on Tensile Strength, Magnetism, Bioactivity, and Antimicrobial Activity

Materials ◽

10.3390/ma14164643 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4643

Author(s):

Hamisah Ismail ◽

Farah ‘Atiqah Abdul Azam ◽

Zalita Zainuddin ◽

Hamidun Bunawan ◽

Muhamad Afiq Akbar ◽

...

Keyword(s):

Antimicrobial Activity ◽

Tensile Strength ◽

Body Fluid ◽

Rice Husk Ash ◽

Antibacterial Properties ◽

Bone Defects ◽

Antibacterial Efficacy ◽

In Vitro Bioactivity ◽

Defect Recovery

β-wollastonite (βW) has sparked much interest in bone defect recovery and regeneration. Biomaterial-associated infections and reactions between implants with human cells have become a standard clinical concern. In this study, a green synthesized βW, synthesized from rice husk ash and a calcined limestone precursor, was incorporated with mullite, maghemite, and silver to produce β wollastonite composite (βWMAF) to enhance the tensile strength and antibacterial properties. The addition of mullite to the βWMAF increased the tensile strength compared to βW. In vitro bioactivity, antibacterial efficacy, and physicochemical properties of the β-wollastonite and βWMAF were characterized. βW and βWMAF samples formed apatite spherules when immersed in simulated body fluid (SBF) for 1 day. In conclusion, βWMAF, according to the tensile strength, bioactivity, and antibacterial activity, was observed in this research and appropriate for the reconstruction of cancellous bone defects.

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Mechanical and Thermal Characterization of Natural Intralaminar Hybrid Composites Based on Sisal

Polymers ◽

10.3390/polym12040866 ◽

2020 ◽

Vol 12 (4) ◽

pp. 866 ◽

Cited By ~ 4

Author(s):

Alexandre L. Pereira ◽

Mariana D. Banea ◽

Jorge S.S. Neto ◽

Daniel K.K. Cavalcanti

Keyword(s):

Thermal Properties ◽

Natural Fiber ◽

Hybrid Composites ◽

Thermal Characterization ◽

Mechanical And Thermal Properties ◽

Scanning Calorimetry ◽

Sem Images ◽

The Matrix ◽

American Society ◽

Curaua Fibers

The main objective of this work was to investigate the effect of hybridization on the mechanical and thermal properties of intralaminar natural fiber-reinforced hybrid composites based on sisal. Ramie, sisal and curauá fibers were selected as natural fiber reinforcements for the epoxy matrix based composites, which were produced by the hand lay-up technique. Tensile, flexural and impact tests were carried out according to American society for testing and materials (ASTM) standards to characterize the hybrid composites, while differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to evaluate the thermal properties. It was found that the mechanical properties are improved by hybridization of sisal based composites. The thermal analysis showed that the hybridization did not significantly affect the thermal stability of the composites. A scanning electron microscopy (SEM) was used to examine the fracture surface of the tested specimens. The SEM images showed a brittle fracture of the matrix and fiber breakage near the matrix.

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Micro and nanocomposites of polybutadienebased polyurethane liners with mineral fillers and nanoclay: thermal and mechanical properties

Open Chemistry ◽

10.1515/chem-2017-0006 ◽

2017 ◽

Vol 15 (1) ◽

pp. 46-52 ◽

Cited By ~ 4

Author(s):

Pablo Ross ◽

Germán Escobar ◽

Guillermo Sevilla ◽

Javier Quagliano

Keyword(s):

Thermal Properties ◽

Polymer Chains ◽

Toluene Diisocyanate ◽

Mechanical And Thermal Properties ◽

Scanning Calorimetry ◽

Elongation At Break ◽

Force Microscopy ◽

Atomic Force ◽

Mineral Fillers

AbstractMicro and nanocomposites of hydroxyl terminated polybutadiene (HTPB)-based polyurethanes (NPU) were obtained using five mineral fillers and Cloisite 20A nanoclay, respectively. Samples were prepared by the reaction of HTPB polyol and toluene diisocyanate (TDI), and the chain was further extended with glyceryl monoricinoleate to produce the final elastomeric polyurethanes. Mechanical and thermal properties were studied, showing that mineral fillers (20%w/w) significantly increased tensile strength, in particular nanoclay (at 5% w/w). When nanoclay-polymer dispersion was modified with a silane and hydantoin-bond promoter, elongation at break was significantly increased with respect to NPU with C20A. Thermal properties measured by differential scanning calorimetry (DSC) were not significantly affected in any case. The molecular structure of prepared micro and nanocomposites was confirmed by Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy. Interaction of fillers with polymer chains is discussed, considering the role of silanes in compatibilization of hydrophilic mineral fillers and hydrophobic polymer. The functionalization of nanoclay with HMDS silane was confirmed using FTIR. Microstructure of NPU with C20A nanoclay was confirmed by Atomic Force Microscopy (AFM).

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Hydroxylated boron nitride nanotube‐reinforced polyvinyl alcohol nanocomposite films with simultaneous improvement of mechanical and thermal properties

Polymer Composites ◽

10.1002/pc.25785 ◽

2020 ◽

Vol 41 (12) ◽

pp. 5182-5194

Author(s):

Xiaolong Lu ◽

Pranjal Nautiyal ◽

Jenniffer Bustillos ◽

Archana Loganathan ◽

Cheng Zhang ◽

...

Keyword(s):

Thermal Properties ◽

Boron Nitride ◽

Polyvinyl Alcohol ◽

Nanocomposite Films ◽

Mechanical And Thermal Properties ◽

Boron Nitride Nanotube

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Cytocompatibility and Antibacterial Properties of Capping Materials

The Scientific World JOURNAL ◽

10.1155/2014/181945 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 30

Author(s):

Claudio Poggio ◽

Carla Renata Arciola ◽

Riccardo Beltrami ◽

Annachiara Monaco ◽

Alberto Dagna ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antibacterial Activity ◽

Antibacterial Properties ◽

Disc Diffusion ◽

Streptococcus Salivarius ◽

Diffusion Test ◽

Streptococcus Sanguis ◽

Agar Disc ◽

Bacterial Growth Inhibition

The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challengedin vitrowithStreptococcus mutans,Streptococcus salivarius, andStreptococcus sanguisin the agar disc diffusion test. Cytocompatibility of the assayed materials towards rat MDPC-23 cells was evaluated at different times by both MTT and apoptosis assays. Results significantly differed among the different materials tested. Both bacterial growth inhibition halos and cytocompatibility performances were significantly different among materials with different composition. MTA-based products showed lower cytotoxicity and valuable antibacterial activity, different from calcium hydroxide-based materials, which exhibited not only higher antibacterial activity but also higher cytotoxicity.

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