Spraying Cellulose Nanofibrils for Improvement of Tensile and Barrier Properties of Writing & Printing (W&P) Paper

Abstract Cellulose based nanomaterials have the great potential to be applied to paper as bulk additive or coating material to improve overall final properties, especially in secondary fiber. In the present work, the effect of applying different kinds of cellulose nanofibrils (CNF) to papers obtained from recycled fibers using size press on physical, mechanical and barrier properties was investigated and compared with the sole use of starch as coating material. The coating process of CNF was carried out by the addition of size press grade starch to coating suspension. As a cellulose source, wheat straw was evaluated and CNF was obtained through oxidative and enzymatic pretreatments. Results indicate that starch/CNF suspension improves the overall paper properties. As a result of the deposition of coating suspension contains of 4 % wt. periodate-oxidized CNF onto paper surface, tensile and burst indices of papersheets increased as 52.2 % and 194.4 %. Significant decreases were observed in air permeability as 69.8 %. Compression tests also have been conducted to evaluate papersheets end-use properties. In comparison to the other pretreated CNF, due to is lower viscosity, applying periodate-oxidized CNF as size press significantly increased the mechanical properties of the papers fabricated from the recycled pulps.

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Robust Guar Gum/Cellulose Nanofibrils Multilayer Films with Good Barrier Properties

ACS Applied Materials & Interfaces ◽

10.1021/acsami.6b14471 ◽

2017 ◽

Vol 9 (6) ◽

pp. 5477-5485 ◽

Cited By ~ 60

Author(s):

Lei Dai ◽

Zhu Long ◽

Jie Chen ◽

Xingye An ◽

Dong Cheng ◽

...

Keyword(s):

Guar Gum ◽

Cellulose Nanofibrils ◽

Barrier Properties ◽

Multilayer Films

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Developed Chitosan/Oregano Essential Oil Biocomposite Packaging Film Enhanced by Cellulose Nanofibril

Polymers ◽

10.3390/polym12081780 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1780

Author(s):

Shunli Chen ◽

Min Wu ◽

Caixia Wang ◽

Shun Yan ◽

Peng Lu ◽

...

Keyword(s):

Tensile Strength ◽

Essential Oil ◽

Food Packaging ◽

Transmission Rate ◽

Cellulose Nanofibrils ◽

Barrier Properties ◽

Light Transmittance ◽

Rate Reduction ◽

Packaging Film ◽

Oregano Essential Oil

The use of advanced and eco-friendly materials has become a trend in the field of food packaging. Cellulose nanofibrils (CNFs) were prepared from bleached bagasse pulp board by a mechanical grinding method and were used to enhance the properties of a chitosan/oregano essential oil (OEO) biocomposite packaging film. The growth inhibition rate of the developed films with 2% (w/w) OEO against E. coli and L. monocytogenes reached 99%. With the increased levels of added CNFs, the fibrous network structure of the films became more obvious, as was determined by SEM and the formation of strong hydrogen bonds between CNFs and chitosan was observed in FTIR spectra, while the XRD pattern suggested that the strength of diffraction peaks and crystallinity of the films slightly increased. The addition of 20% CNFs contributed to an oxygen-transmission rate reduction of 5.96 cc/m2·day and water vapor transmission rate reduction of 741.49 g/m2·day. However, the increase in CNFs contents did not significantly improve the barrier properties of the film. The addition of 60% CNFs significantly improved the barrier properties of the film to light and exhibited the lowest light transmittance (28.53%) at 600 nm. Addition of CNFs to the chitosan/OEO film significantly improved tensile strength and the addition of 60% CNFs contributed to an increase of 16.80 MPa in tensile strength. The developed chitosan/oregano essential oil/CNFs biocomposite film with favorable properties and antibacterial activity can be used as a green, functional material in the food-packaging field. It has the potential to improve food quality and extend food shelf life.

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Effect of Overlapping Eco-Friendly Cellulose Nanofibrils and Nanoclay Layers on Mechanical and Barrier Properties of Spray-Coated Papers

10.21203/rs.3.rs-897414/v1 ◽

2021 ◽

Author(s):

Maria Luiza Cafalchio de Oliveira ◽

Seyedmohammad Mirmehdi ◽

Mário Vanoli Scatolino ◽

Mario Guimarães Júnior ◽

Anand Ramesh Sanadi ◽

...

Keyword(s):

Tensile Strength ◽

Raw Materials ◽

Transmission Rate ◽

Cellulose Nanofibrils ◽

Spray Coating ◽

Barrier Properties ◽

Contact Angles ◽

Renewable Raw Materials ◽

Coated Papers ◽

Lower Contact

Abstract This work proposes to evaluate the effect of spray-coating in papers using eco-friendly cellulose nanofibrils (CNFs) and nanoclay (NC) on mechanical and barrier properties for application as reinforced bags. Sack kraft papers of 60 g m-² (C60) were coated with CNFs + CNFs/NC in 4 layers (L5), 40 g m-² of CNFs + CNFs/NC in 3 layers (L4), 30 g m-² with CNFs/NC in 2 layers (L3) and 10 g m-² of CNFs in 1 layer (L2), and compared to uncoated sack kraft papers with basis weight of 60 g m-² (C60), 80 g m-² (C80) and 120 g m-² (C120). The coated papers L2; L3; L4 and L5 obtained a decrease in water vapor transmission rate (WVTR) of 3.5%; 17%; 14% and 14%, respectively, when compared to C60. Comparing L2 and L3, CNF layer induced lower contact angles on the coated paper than CNF/NC layer. When compared coated papers with C120, it was observed an increase of around 66% in tensile strength for L2, around 44% for L3, and decrease of ~ 18% for L5 coated papers. L4 achieved the same tensile strength (when divided by basis weight) than C120. L2 and L3 coated papers led to the highest values of Young’s modulus, with increase of 56% and 38%, respectively, when compared to C60. Spray-coating in the present conditions improved the mechanical and barrier properties of the coated papers, being a possible alternative to produce papers with lower basis weight and using renewable raw materials.

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Role of Cellulose Nanofibrils in Improving the Strength Properties of Papers: A Review

10.21203/rs.3.rs-729909/v1 ◽

2021 ◽

Author(s):

Thabisile Brightwell Jele ◽

Prabashni Lekha ◽

Bruce Sithole

Keyword(s):

Cellulose Nanofibrils ◽

High Strength ◽

Barrier Properties ◽

Strength Properties ◽

Biochemical Properties ◽

Factors Affecting ◽

Tear Index ◽

Different Types ◽

Breaking Length

Abstract The pursuit for sustainability in the papermaking industry calls for the elimination or reduction of synthetic additives and the exploration of renewable and biodegradable alternatives. Cellulose nanofibrils (CNFs), due to their inherent morphological and biochemical properties, are an excellent alternative to synthetic additives. These properties enable CNFs to improve the mechanical, functional and barrier properties of different types of paper. The nanosize diameter, micrometre length, semi-crystalline structure, high strength and modulus of CNFs has a direct influence on the mechanical properties of paper such as tensile index, burst index, Scott index, breaking length, tear index, Z-strength, E-modulus, strain at break, and tensile stiffness. This review details the role played by CNFs as an additive to improve strength properties of papers and the factors affecting the improvement in paper quality when CNFs are added as additives. The paper also includes techno-economic aspects of the process and identifies areas that need further research.

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Hybrid films from plant and bacterial nanocellulose: mechanical and barrier properties

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2021-0036 ◽

2022 ◽

Vol 0 (0) ◽

Author(s):

Thiago Moreira Cruz ◽

Adriano Reis Prazeres Mascarenhas ◽

Mário Vanoli Scatolino ◽

Douglas Lamounier Faria ◽

Lays Camila Matos ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Water Vapor ◽

Mechanical Performance ◽

Cellulose Nanofibrils ◽

Water Vapor Permeability ◽

Barrier Properties ◽

Contact Angles ◽

Vapor Permeability ◽

Hybrid Films

Abstract The accumulation of petroleum polymers compromises biodiversity and causes environmental problems. Nanocellulose enhances biodegradability and can improve the physical-mechanical performance of materials. The objective was to produce and characterize hybrid films composed of bacterial cellulose (BC) and plant nanocellulose from Eucalyptus (Euc) or Pinus (Pin). Films were produced by the casting method using filmogenic suspensions with different cellulose nanofibrils (CNFs) proportions from both the sources (0, 25, 50, 75 and 100 %). CNFs suspensions were characterized by transmission electron microscopy. The morphology of the films was analyzed using scanning electron microscopy. In addition, the transparency, contact angle, wettability, oil and water vapor barrier and mechanical properties were also evaluated. The contact angles were smaller for films with BC and the wettability was greater when comparing BC with plant CNFs (0.10 ° s − 1 {\text{s}^{-1}} for 75 % Euc/25 % BC and 0.20 ° s − 1 {\text{s}^{-1}} for 25 % Euc/75 % BC). The water vapor permeability (WVP) of the 100 % BC films and the 25 % Euc/75 % BC composition were the highest among the studied compositions. Tensile strength, Young’s modulus and puncture strength decreased considerably with the addition of BC in the films. More studies regarding pre-treatments to purify BC are needed to improve the mechanical properties of the films.

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Barrier coatings with various types of cellulose nanofibrils and their barrier properties

Cellulose ◽

10.1007/s10570-020-03061-5 ◽

2020 ◽

Vol 27 (8) ◽

pp. 4509-4523 ◽

Cited By ~ 4

Author(s):

Simyub Yook ◽

Heetae Park ◽

Hyeonji Park ◽

Sun-Young Lee ◽

Jaegyung Kwon ◽

...

Keyword(s):

Cellulose Nanofibrils ◽

Barrier Properties ◽

Barrier Coatings

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Influence of Lactic Acid Surface Modification of Cellulose Nanofibrils on the Properties of Cellulose Nanofibril Films and Cellulose Nanofibril–Poly (Lactic Acid) Composites

Biomolecules ◽

10.3390/biom11091346 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1346

Author(s):

Ruth Anayimi Lafia-Araga ◽

Ronald Sabo ◽

Omid Nabinejad ◽

Laurent Matuana ◽

Nicole Stark

Keyword(s):

Lactic Acid ◽

Water Vapor ◽

Water Absorption ◽

Aqueous Medium ◽

Cellulose Nanofibrils ◽

Barrier Properties ◽

Poly Lactic Acid ◽

Esterification Reaction ◽

Cellulose Nanofibril ◽

Cnf Films

In this study, cellulose nanofibrils (CNFs) were modified by catalyzed lactic acid esterification in an aqueous medium with SnCl2 as a catalyst. Films were made from unmodified and lactic acid-modified CNF without a polymer matrix to evaluate the effectiveness of the modification. Ungrafted and lactic acid-grafted CNF was also compounded with poly(lactic acid) (PLA) to produce composites. Mechanical, water absorption, and barrier properties were evaluated for ungrafted CNF, lactic acid-grafted CNF films, and PLA/CNF composites to ascertain the effect of lactic acid modification on the properties of the films and nanocomposites. FTIR spectra of the modified CNF revealed the presence of carbonyl peaks at 1720 cm−1, suggesting that the esterification reaction was successful. Modification of CNF with LA improved the tensile modulus of the produced films but the tensile strength and elongation decreased. Additionally, films made from modified CNF had lower water absorption, as well as water vapor and oxygen permeability, relative to their counterparts with unmodified CNFs. The mechanical properties of PLA/CNF composites made from lactic acid-grafted CNFs did not significantly change with respect to the ungrafted CNF. However, the addition of lactic acid-grafted CNF to PLA improved the water vapor permeability relative to composites containing ungrafted CNF. Therefore, the esterification of CNFs in an aqueous medium may provide an environmentally benign way of modifying the surface chemistry of CNFs to improve the barrier properties of CNF films and PLA/CNF composites.

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Cellulose nanofibrils improve the properties of all-cellulose composites by the nano-reinforcement mechanism and nanofibril-induced crystallization

Nanoscale ◽

10.1039/c5nr05511c ◽

2015 ◽

Vol 7 (42) ◽

pp. 17957-17963 ◽

Cited By ~ 41

Author(s):

Quanling Yang ◽

Tsuguyuki Saito ◽

Lars A. Berglund ◽

Akira Isogai

Keyword(s):

Cellulose Nanofibrils ◽

Barrier Properties ◽

Regenerated Cellulose ◽

Oxygen Barrier ◽

Cellulose Nanofibril ◽

High Mechanical Strength ◽

Reinforcement Mechanism ◽

Cellulose Composites ◽

The Matrix ◽

Induced Crystallization

Transparent all-cellulose composites prepared from cellulose nanofibrils and regenerated cellulose exhibit high mechanical strength, stiffness, thermal stability, and oxygen barrier properties with only 1% cellulose nanofibril content, resulting from the nano-reinforcement mechanism and nanofibril-induced crystallization of cellulose molecules in the matrix.

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