Effect of Molecular Weight and Degree of Substitution on the Physical-Chemical Properties of Methylcellulose-Starch Nanocrystal Nanocomposite Films

This research studied the effect of molecular weight (Mw) and degree of substitution (DS) on the microstructure and physicochemical characteristics of methylcellulose (MC) films with or without SNC. The Mw and DS of three types of commercial MC (trade name of M20, A4C, and A4M, respectively) were in the range of 0.826 to 3.404 × 105 Da and 1.70 to 1.83, respectively. Mw significantly affected the viscosity of methylcellulose solutions as well as the microstructure and tensile strength of methylcellulose films, while DS had a pronounced effect on their oxygen permeability properties. The incorporation of 15% (w/w) SNC resulted in the efficient improvement of tensile strength, water, and oxygen barrier properties of films, particularly for the A4C nanocomposite films. The results from SEM and FTIR illustrated that relatively homogenous dispersion of SNC was distinguished in A4C-15% (w/w) SNC films. Furthermore, microstructures of MC-SNC nanocomposite films were strongly dependent on both Mw and DS of MC. This work offers a convenient and green method to fabricate MC-based nanocomposite films with desirable mechanical, light, oxygen, and water vapor barrier properties.

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Preparation and Properties Research of Modified Nano-ZnO/HDPE Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.174.450 ◽

2010 ◽

Vol 174 ◽

pp. 450-453 ◽

Cited By ~ 1

Author(s):

Ya Na Li ◽

Kyong Ho Cha ◽

Qing Hui He

Keyword(s):

Tensile Strength ◽

Water Vapor ◽

Zno Nanoparticles ◽

Composite Films ◽

Barrier Properties ◽

Nanocomposite Films ◽

Melt Blending ◽

Molding Process ◽

Nano Zno ◽

Modified Zno Nanoparticles

Nanocomposite films of ZnO/HDPE were prepared via melt blending and hot compression molding process. The morphology, DSC, mechanical and barrier properties of the films were investigated. The results showed that a better dispersion of modified nanoparticles at content of 0.5wt% in HDPE matrix occurred and the improvement of the HDPE films in tensile strength and tear strength was achieved by incorporating modified-ZnO nanoparticles up to 0.5wt% in contrast with the original nano-ZnO/HDPE composite films. It was also found that the addition of modified nano-ZnO to neat HDPE caused to increase crystallinity and enhance the barrier property of nano-ZnO/HDPE composite films against water vapor and oxygen.

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Effects of Organo-Modified Clay Addition and Temperature on the Water Vapor Barrier Properties of Polyhydroxy Butyrate Homo and Copolymer Nanocomposite Films for Packaging Applications

Journal of Polymers and the Environment ◽

10.1007/s10924-017-1017-2 ◽

2017 ◽

Vol 26 (3) ◽

pp. 1121-1132 ◽

Cited By ~ 18

Author(s):

Okan Akin ◽

Funda Tihminlioglu

Keyword(s):

Water Vapor ◽

Barrier Properties ◽

Nanocomposite Films ◽

Modified Clay ◽

Water Vapor Barrier ◽

Polyhydroxy Butyrate

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The Kinetics and Occurrence of Optimum Vulcanization

Rubber Chemistry and Technology ◽

10.5254/1.3542555 ◽

1956 ◽

Vol 29 (2) ◽

pp. 555-567

Author(s):

B. A. Dogadkin

Keyword(s):

Molecular Weight ◽

Tensile Strength ◽

Structure Formation ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Smooth Curves ◽

Intermolecular Reaction ◽

Physical And Chemical ◽

Kinetics Of ◽

And Chemical Properties

Abstract The fundamental reaction of vulcanization is the combination of a vulcanizing agent with rubber. The kinetics of this reaction is expressed by smooth curves. Simultaneously with the combining of the vulcanizing agent, in fact as a result of it, changes take place in a number of physical and chemical properties of rubber—solubility, modulus, tensile strength, and other indexes. Unlike the kinetics of combination of the vulcanizing agent, the changes in these properties are most often represented by curves having a maximum or minimum which characterizes the phenomenon of optimum vulcanization. The extreme form which curves of changes of physical and chemical properties of rubber assume during vulcanization can be explained, in our opinion, by the fact that, during vulcanization, there is a competition between opposing reactions, of which one set are reactions of structure formation (i.e., increase of the molecular weight and the intensity of intermolecular reaction), and the others are destruction reactions. Thus, during vulcanization under factory conditions, at least two reactions take place: (1) the reaction between rubber and sulfur, and (2) the reaction between rubber and molecular oxygen introduced into the vulcanization mix by milling with the ingredients. The amount of oxvgen present here in moles approaches the molar concentration of sulfur.

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Eco-Friendly, Green Packaging Materials from Akaganeite and Hematite Nanoparticle-Reinforced Chitosan Nanocomposite Films

Journal of Nanomaterials ◽

10.1155/2019/1049142 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11

Author(s):

G. T. D. Chandrakumara ◽

D. M. S. N. Dissanayake ◽

M. M. M. G. P. G. Mantilaka ◽

R. T. De Silva ◽

H. M. T. G. A. Pitawala ◽

...

Keyword(s):

Chemical Properties ◽

Barrier Properties ◽

Tensile Tests ◽

Maximum Tensile Stress ◽

Nanocomposite Films ◽

Iron Oxide Nanoparticle ◽

Electron Microscopic ◽

Sem Images ◽

Chitosan Matrix ◽

Green Packaging

In this study, chitosan nanocomposite thin films were successfully fabricated by incorporating hematite nanoparticles (HNPs) and akaganeite nanoparticles (ANPs) as reinforcing fillers using the solution casting method. HNPs and ANPs were synthesized via a urea-assisted synthesis route using naturally occurring ferruginous laterites. Scanning electron microscopic (SEM) images indicated the spherical to subhexagonal morphology of the HNPs and rice-like morphology of the ANPs. X-ray diffractograms indicate the crystalline structure of iron oxides as hematite and akaganeite. Tensile tests were carried out to evaluate the mechanical properties of the nanocomposite films where maximum tensile stress of the chitosan/HNP composites was improved as high as 35.7% while chitosan/ANP composites indicated 43.5%. Thermal decomposition curves obtained by thermogravimetric analysis (TGA) indicate that the thermal stability of the nanocomposites has improved remarkably compared to neat chitosan films. Furthermore, these nanocomposites exhibited excellent UV barrier properties as identified by UV-visible spectrometry. Fourier-transform infrared (FTIR) spectroscopic results are evident in the presence of Fe-O bond in the wavenumber around 480-500 cm-1, and the result also indicated that the nanofillers interact with the chitosan matrix via hydrogen bonding, which enhanced the physical properties of the nanocomposites. Incorporation of iron oxide nanoparticle varieties into chitosan has led to improvements of certain physical and chemical properties, which make chitosan a promising material for packaging applications.

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PLA/Halloysite Nanocomposite Films: Water Vapor Barrier Properties and Specific Key Characteristics

Macromolecular Materials and Engineering ◽

10.1002/mame.201200424 ◽

2013 ◽

Vol 299 (1) ◽

pp. 104-115 ◽

Cited By ~ 94

Author(s):

Giuliana Gorrasi ◽

Roberto Pantani ◽

Marius Murariu ◽

Philippe Dubois

Keyword(s):

Water Vapor ◽

Barrier Properties ◽

Nanocomposite Films ◽

Water Vapor Barrier ◽

Key Characteristics

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Effect of clay contents on mechanical and water vapor barrier properties of agar-based nanocomposite films

Carbohydrate Polymers ◽

10.1016/j.carbpol.2011.05.010 ◽

2011 ◽

Vol 86 (2) ◽

pp. 691-699 ◽

Cited By ~ 207

Author(s):

Jong-Whan Rhim

Keyword(s):

Water Vapor ◽

Barrier Properties ◽

Nanocomposite Films ◽

Water Vapor Barrier

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PLA-ZnO nanocomposite films: Water vapor barrier properties and specific end-use characteristics

European Polymer Journal ◽

10.1016/j.eurpolymj.2013.08.005 ◽

2013 ◽

Vol 49 (11) ◽

pp. 3471-3482 ◽

Cited By ~ 125

Author(s):

Roberto Pantani ◽

Giuliana Gorrasi ◽

Giovanni Vigliotta ◽

Marius Murariu ◽

Philippe Dubois

Keyword(s):

Water Vapor ◽

Barrier Properties ◽

Nanocomposite Films ◽

Water Vapor Barrier ◽

End Use

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Mechanical and Barrier Properties of PVP-Carbon Dot Nanocomposite Films

Jurnal Kimia Terapan Indonesia ◽

10.14203/jkti.v20i2.392 ◽

2019 ◽

Vol 20 (2) ◽

pp. 49-56

Author(s):

Ahmad Sjahriza ◽

Zainal Alim Mas’ud ◽

Komar Sutirah

Keyword(s):

Thermal Stability ◽

Tensile Strength ◽

Citric Acid ◽

Melting Process ◽

Barrier Properties ◽

Single Step ◽

Nanocomposite Films ◽

Carbon Dot ◽

Microwave Process ◽

Water Vapour Barrier

This research reported carbon dot were synthesized form citric acid and urea through a single step microwave process and Poly Vinyl Pirrolidone (PVP) films composited by carbon dot were prepared. The effects of different composition carbon dots on mechanical strength of films and water vapour barrier were evaluated. Highest mechanical yielded composite film were analyzed their thermal stability. Average of carbon dot diameter was found 90.61 nm and polydispersity indice 0.396. Different composition carbon dot exhibit significant improvement in tensile strength and modulus. Water permeablity of films varieate with content of carbon dot. The presence of carbon dot had a negligible effect on Tg of film and show melting process.

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Nanoarchitectonics Composites of Thermoplastic Starch and Montmorillonite Modified with Low Molecular Weight Polylactic Acid

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17457 ◽

2020 ◽

Vol 20 (5) ◽

pp. 2955-2963

Author(s):

Peixian Li ◽

Huimin Guo ◽

Kaixiong Yang ◽

Xiaoyan Yu ◽

Xiongwei Qu ◽

...

Keyword(s):

Mechanical Properties ◽

Molecular Weight ◽

Tensile Strength ◽

Polylactic Acid ◽

Composite Films ◽

Thermoplastic Starch ◽

Nanocomposite Films ◽

Low Molecular Weight ◽

Elongation At Break ◽

Starch Films

Nano montmorillonite (MMT) was modified by low molecular weight polylactic acid (PLA), then, the PLA modified MMT and raw MMT were added into thermoplastic starch (TPS) to prepare biodegradable nanocomposite films, respectively. For both nanocomposite films with raw MMT and modified MMT, the Tmax of degradation was enhanced and the mechanical properties were improved. The composite films containing 4 wt.% MMT displayed tensile strength of 5.06 MPa, approximately 1.4 times of that for the pure TPS films. The tensile strength of composite films containing 4 wt.% modified MMT is 6.74 MPa approximately 2 times of those for pure starch films. On the other hand, the composite film containing 4 wt.% modified MMT displayed elongation at break as high as 34.25%, which is 1.3 times of that of the pure starch film, while the composite films containing raw MMT had reduced elongation at break. This study showed that the MMT modified with PLA could significantly enhance the mechanical properties of TPS, and provides a new method to prepare fully biodegradable starch-based nanocomposites.

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