Transparent Ultraviolet (UV)-Shielding Films Made from Waste Hemp Hurd and Polyvinyl Alcohol (PVA)

This work proposes a new approach to fabricate highly transparent and flexible composite films that exhibit enhanced UV-shielding properties. Lignin has innate UV-shielding properties. However, when purified lignin, which is conventionally extracted through chemical treatment, is mixed with polymeric materials, its presence negatively influences the transparency of the resulting composite. High transparency and UV-shielding are desirable properties for many applications. In this study, composites were made by mixing lignocellulose particles and polyvinyl alcohol (PVA), where lignocellulose particles were obtained from ball-milled waste hemp hurd without chemical treatments. The UV-shielding properties of the resulting composite film, as a function of hemp/PVA weight ratios, were investigated. The intermolecular interactions between the hemp particles and the PVA were characterized using infrared spectroscopy with the presence of –C=O group at 1655 cm−1, providing evidence that the chemical structure of lignin was preserved. The fabricated hemp/PVA films exhibit stronger UV-shielding, in the UVA-I range (340–400 nm) than TiO2/PVA films. The composite films also showed comparable water vapor permeability (WVP) with commercial packaging plastic film made of HDPE (high-density polyethylene). The optimization experiments were reported, with aim at understanding the balance between the UV-shielding and mechanical properties of the hemp/PVA films. The findings of this work can be applicable to the packaging, food and cosmetic industries where UV shielding is of utmost importance, hence adding value to hemp hurd waste.

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Morphology of poly(3-hydroxybutyrate)–polyvinyl alcohol extrusion films

Journal of Polymer Engineering ◽

10.1515/polyeng-2014-0202 ◽

2015 ◽

Vol 35 (8) ◽

pp. 765-771 ◽

Cited By ~ 5

Author(s):

Anatoly A. Ol’khov ◽

Alexey L. Iordanskii ◽

Tamara P. Danko

Keyword(s):

Water Vapor ◽

Polyvinyl Alcohol ◽

Relative Elongation ◽

Composite Films ◽

Tensile Modulus ◽

Water Vapor Permeability ◽

Vapor Permeability ◽

Scanning Calorimetry ◽

X Ray ◽

Extruded Films

Abstract The morphology of extruded films based on blends of polyvinyl alcohol (PVA) and poly(3-hydroxybutyrate) (PHB) was studied for various compositions. The methods of differential scanning calorimetry (DSC) and X-ray analysis were used. The phase-sensitive characteristics of the composite films, diffusion and water vapor permeability were also investigated. Processes of binding of water and swelling cause the first areas; processes of a relaxation and transition of structure of composites to an equilibrium condition, the second. In addition, the tensile modulus and relative elongation-at-break were measured. Changes in the glass transition temperature (Tg) of the blends and constant melting points of the components show their partial compatibility in intercrystalline regions. At a content of PHB in the composite films equal to 20–30% wt., the mechanical characteristics and water diffusion coefficients are dramatically changed. This fact, along with the analysis of the X-ray diffractograms, indicates a phase inversion in the above narrow concentration interval. The complex pattern of the kinetic curves of water vapor permeability is likely to be related to additional crystallization, which is induced in the composite films in the presence of water.

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Mechanical and Barrier Properties of Composite Films Based on Kappa-Carrageenan-Polyvinyl Alcohol

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.f1090.0986s319 ◽

2019 ◽

Vol 8 (6S3) ◽

pp. 489-499

Keyword(s):

Tensile Strength ◽

Water Vapor ◽

Moisture Content ◽

Polyvinyl Alcohol ◽

Water Solubility ◽

Composite Films ◽

Water Vapor Permeability ◽

Vapor Permeability ◽

Burst Strength ◽

Kappa Carrageenan

Optimization of film formula-based kappa-carrageenan and polyvinyl alcohol (PVA) was studied using a two-level, two-factor Design Expert 11® by Response Surface Methodology (RSM) Central Composite Design (CCD). The aim of this study was to obtain the optimal concentration of kappa-carrageenan and polyvinyl alcohol in producing films. The influence composition ⱪ-carrageenan and polyvinyl alcohol was characterized. The results showed the effects of k-carrageenan and polyvinyl alcohol had a significant effect on the response thickness, tensile strength, burst strength, elongation, solubility, water vapor barrier, opacity, color, and moisture content. The optimized condition for production k-carrageenan and PVA was 1.21% carrageenan and 1.93% polyvinyl alcohol, which was giving film with thickness 0.044 mm, tensile strength 16.69 MPa, burst strength 167.86 kPa, elongation 81.79%, water solubility 65.04%, water vapor permeability 7.49 g/m s Pa x 10-11, opacity 2.31, ΔE 2.42, and moisture content 19.13%

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Ultraviolet blocking and antioxidant polyvinyl alcohol films incorporated with baicalin extraction from Scutellaria baicalensis Georgi

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0071 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Jinshu Liu ◽

Xiaoyan Ma ◽

Wenzhao Shi ◽

Jianwei Xing ◽

Chaoqun Ma ◽

...

Keyword(s):

Water Vapor ◽

Polyvinyl Alcohol ◽

Radical Scavenging Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Water Vapor Permeability ◽

Scutellaria Baicalensis ◽

Vapor Permeability ◽

Protective Film ◽

Uv Blocking

Abstract Baicalin, an active flavonoid ingredient of Scutellaria baicalensis Georgi, was extracted by heat reflux extraction and showed the same significance UV absorption property with standard baicalin. Active films were prepared from polyvinyl alcohol (PVA) containing baicalin extract by casting method. The effect of baicalin extracts on the UV-blocking, optical, antioxidant property, water vapor permeability, swelling and mechanical properties of the films were studied. UV–vis transmittance spectra showed that PVA films incorporated with baicalin extract blocked ultraviolet light range from 280–400 nm even with low concentration of baicalin (0.5 wt%) and maintain the high transparency in visible spectrum. The outstanding UV-blocking properties of PVA films incorporated with baicalin extract were also confirmed by Rhodamine B degradation. Baicalin conferred antioxidant properties to PVA films as determined by DPPH radical scavenging activity. Due to the interaction between hydroxy groups of baicalin and PVA molecule, water vapor permeability, swelling and elongation at break of the films were decreased accompanied with the increasing in tensile strength and Young’s modulus. FTIR reveal that the interaction between PVA molecules was significant changed by the introduction of baicalin. These results suggest that PVA film incorporated with baicalin extract can be used for the development of functional protective film.

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Few-layer graphene aqueous suspensions for polyurethane composite coatings

MRS Advances ◽

10.1557/adv.2016.640 ◽

2016 ◽

Vol 2 (1) ◽

pp. 57-62 ◽

Cited By ~ 2

Author(s):

Eunice Cunha ◽

Fernando Duarte ◽

M. Fernanda Proença ◽

M. Conceição Paiva

Keyword(s):

Mechanical Properties ◽

Tensile Testing ◽

Composite Coatings ◽

Composite Films ◽

Water Vapor Permeability ◽

Waterborne Polyurethane ◽

Vapor Permeability ◽

Layer Graphene ◽

Polyurethane Composite ◽

Few Layer Graphene

ABSTRACTGraphite nanoplates (GnP) have recently attracted attention as an economically viable alternative for the development of functional and structural nanocomposites. The incorporation of GnP into waterborne polyurethane (WPU) with loadings from 0.1 to 10 wt.% was studied. The mechanical properties of the composite films were assessed by tensile testing showing an increase of the Young’s modulus up to 48%. The electrical conductivity increased by 9 orders of magnitude and the water vapor permeability of the composite films decreased 57% for composites containing 5.0 wt.% of GnP.

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Fabrication of Composite Films Based on Chitosan and Vegetable-Tanned Collagen Fibers Crosslinked with Genipin

Journal of the American Leather Chemists Association ◽

10.34314/jalca.v116i10.4616 ◽

2021 ◽

Vol 116 (10) ◽

Author(s):

Jie Liu ◽

Yanchun Liu ◽

Eleanor M. Brown ◽

Zhengxin Ma ◽

Cheng-Kung Liu

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Water Vapor ◽

Composite Film ◽

Composite Films ◽

Value Added ◽

Water Vapor Permeability ◽

Vapor Permeability ◽

Leather Industry ◽

Compact Structure

The leather industry generates considerable amounts of solid waste and raises many environmental concerns during its disposal. The presence of collagen in these wastes provides a potential protein source for the fabrication of bio-based value-added products. Herein, a novel composite film was fabricated by incorporating vegetable-tanned collagen fiber (VCF), a mechanically ground powder-like leather waste, into a chitosan matrix and crosslinked with genipin. The obtained composite film showed a compact structure and the hydrogen bonding interactions were confirmed by FTIR analysis, indicating a good compatibility between chitosan and VCF. The optical properties, water absorption capacity, thermal stability, water vapor permeability and mechanical properties of the composite films were characterized. The incorporation of VCF into chitosan led to significant decreases in opacity and solubility of the films. At the same time, the mechanical properties, water vapor permeability and thermal stability of the films were improved. The composite film exhibited antibacterial activity against food-borne pathogens. Results from this research indicated the potential of the genipin-crosslinked chitosan/VCF composites for applications in antimicrobial packaging.

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Improving the Performance of Feather Keratin/Polyvinyl Alcohol/Tris(hydroxymethyl)Aminomethane Nanocomposite Films by Incorporating Graphene Oxide or Graphene

Nanomaterials ◽

10.3390/nano10020327 ◽

2020 ◽

Vol 10 (2) ◽

pp. 327 ◽

Cited By ~ 1

Author(s):

Shufang Wu ◽

Xunjun Chen ◽

Tiehu Li ◽

Yingde Cui ◽

Minghao Yi ◽

...

Keyword(s):

Graphene Oxide ◽

Polyvinyl Alcohol ◽

Water Vapor Permeability ◽

Nanocomposite Films ◽

Light Transmittance ◽

Vapor Permeability ◽

Blend Films ◽

Feather Keratin ◽

Degradation Temperature ◽

Bionanocomposite Films

In this study, feather keratin/polyvinyl alcohol/tris(hydroxymethyl)aminomethane (FK/PVA/Tris) bionanocomposite films containing graphene oxide (GO) (0.5, 1, 2, and 3 wt%) or graphene (0.5, 1, 2, and 3 wt%) were prepared using a solvent casting method. The scanning electron microscopy results indicated that the dispersion of GO throughout the film matrix was better than that of graphene. The successful formation of new hydrogen bonds between the film matrix and GO was confirmed through the use of Fourier-transform infrared spectroscopy. The tensile strength, elastic modulus, and initial degradation temperature of the films increased, whereas the total soluble mass, water vapor permeability, oxygen permeability, and light transmittance decreased following GO or graphene incorporation. In summary, nanoblending is an effective method to promote the application of FK/PVA/Tris-based blend films in the packaging field.

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Preparation and Properties of Corn Starch/Chitin Composite Films Cross-Linked by Maleic Anhydride

Polymers ◽

10.3390/polym12071606 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1606

Author(s):

Peng Yin ◽

Jinglong Liu ◽

Wen Zhou ◽

Panxin Li

Keyword(s):

Maleic Anhydride ◽

Corn Starch ◽

Composite Films ◽

Water Vapor Permeability ◽

Contact Angles ◽

Vapor Permeability ◽

Water Contact ◽

Elongation At Break ◽

Shrimp Shell ◽

Starch Films

To improve the functional properties of starch-based films, chitin (CH) was prepared from shrimp shell powder and incorporated into corn starch (CS) matrix. Before blending, maleic anhydride (MA) was introduced as a cross-linker. Composite CS/MA-CH films were obtained by casting-evaporation approach. Mechanical property estimation showed that addition of 0–7 wt % MA-CH improved the tensile strength of starch films from 3.89 MPa to 9.32 MPa. Elongation at break of the films decreased with the addition of MA-CH, but the decrease was obviously reduced than previous studies. Morphology analysis revealed that MA-CH homogeneously dispersed in starch matrix and no cracks were found in the CS/MA-CH films. Incorporation of MA-CH decreased the water vapor permeability of starch films. The water uptake of the films was reduced when the dosage of MA-CH was below 5 wt %. Water contact angles of the starch films increased from 22° to 86° with 9 wt % MA-CH incorporation. Besides, the composite films showed better inhibition effect against Escherichia coli and Staphylococcus aureus than pure starch films.

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Effect of Sonication Duration in the Performance of Polyvinyl Alcohol/Chitosan Bilayer Films and Their Effect on Strawberry Preservation

Molecules ◽

10.3390/molecules24071408 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1408 ◽

Cited By ~ 2

Author(s):

Jie Ding ◽

Rong Zhang ◽

Saeed Ahmed ◽

Yaowen Liu ◽

Wen Qin

Keyword(s):

Polyvinyl Alcohol ◽

Water Vapor Permeability ◽

Ascorbic Acid Content ◽

Titratable Acidity ◽

Solid Content ◽

Bilayer Film ◽

Vapor Permeability ◽

Soluble Solid Content ◽

Health Food ◽

Bilayer Films

In this study, we fabricated polyvinyl alcohol (PVA)/chitosan (CS) bilayer films by casting and investigated the effects of preparation conditions and CS content (2, 2.5, or 3 wt.%) on the ability of these films to preserve packaged strawberries. The best performance was achieved at a CS loading of 2.5 wt.% (ultrasound time, 25 min); the strain and stress values were 143.15 ± 6.43% and 70.67 ± 0.85 MPa, respectively, oxygen permeability was 0.16 ± 0.08 cm2·m2·day−1·MPa−1, water vapor permeability was 14.93 ± 4.09 g·cm−1·s−1·Pa−1, and the shelf life of fresh strawberries packaged in the PVA/CS 2.5 wt.% bilayer film was determined to be 21 days at 5 ± 2 °C and a relative humidity of 60 ± 5%. Treatment with PVA/CS bilayer films prevented the decrease in the firmness of strawberries during storage (21 days). The evaluated physicochemical parameters (weight loss, decay, firmness, titratable acidity, soluble solid content, ascorbic acid content, and color) indicated that treatment with PVA/CS bilayer films led to better maintenance of the fruit quality. We believe that our study makes a significant contribution to literature because it paves the way to the fabrication of smart packaging materials and facilitates the commercialization of fresh strawberries as an important health food.

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Improving Thermal, Mechanical, and Barrier Properties of Feather Keratin/Polyvinyl Alcohol/Tris(hydroxymethyl)aminomethane Nanocomposite Films by Incorporating Sodium Montmorillonite and TiO2

Nanomaterials ◽

10.3390/nano9020298 ◽

2019 ◽

Vol 9 (2) ◽

pp. 298 ◽

Cited By ~ 4

Author(s):

Shufang Wu ◽

Xunjun Chen ◽

Minghao Yi ◽

Jianfang Ge ◽

Guoqiang Yin ◽

...

Keyword(s):

Polyvinyl Alcohol ◽

Three Dimensional ◽

Water Vapor Permeability ◽

Barrier Properties ◽

Nanocomposite Films ◽

Light Transmittance ◽

Vapor Permeability ◽

Hydroxyl Groups ◽

Sodium Montmorillonite ◽

Feather Keratin

In this study, feather keratin/polyvinyl alcohol/tris(hydroxymethyl)aminomethane (FK/PVA/Tris) bionanocomposite films containing two types of nanoparticles, namely one-dimensional sodium montmorillonite (MMT) clay platelets (0.5, 1, 3, and 5 wt%) and three-dimensional TiO2 nanospheres (0.5, 1, 3, and 5 wt%), are prepared using solvent casting method. X-ray diffraction studies confirm the completely exfoliated structure of FK/PVA/Tris/MMT nanocomposites. The successful formation of new hydrogen bonds between the hydroxyl groups of the film matrix and the nanofillers is confirmed by Fourier transform infrared spectroscopy. The tensile strength, elongation at break, and initial degradation temperature of the films are enhanced after MMT and TiO2 incorporation. The water vapor permeability, oxygen permeability, and light transmittance decrease with increase in TiO2 and MMT contents. In summary, nanoblending is an effective method to promote the application of FK/PVA/Tris blend films in the packaging field.

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