scholarly journals Influence of biological origin on the tensile properties of cellulose nanopapers

Cellulose ◽  
2021 ◽  
Author(s):  
Katri S. Kontturi ◽  
Koon-Yang Lee ◽  
Mitchell P. Jones ◽  
William W. Sampson ◽  
Alexander Bismarck ◽  
...  

Abstract Cellulose nanopapers provide diverse, strong and lightweight templates prepared entirely from sustainable raw materials, cellulose nanofibers (CNFs). Yet the strength of CNFs has not been fully capitalized in the resulting nanopapers and the relative influence of CNF strength, their bonding, and biological origin to nanopaper strength are unknown. Here, we show that basic principles from paper physics can be applied to CNF nanopapers to illuminate those relationships. Importantly, it appeared that ~ 200 MPa was the theoretical maximum for nanopapers with random fibril orientation. Furthermore, we demonstrate the contrast in tensile strength for nanopapers prepared from bacterial cellulose (BC) and wood-based nanofibrillated cellulose (NFC). Endemic amorphous polysaccharides (hemicelluloses) in NFC act as matrix in NFC nanopapers, strengthening the bonding between CNFs just like it improves the bonding between CNFs in the primary cell wall of plants. The conclusions apply to all composites containing non-woven fiber mats as reinforcement. Graphic abstract

2021 ◽  
Vol 904 ◽  
pp. 309-314
Author(s):  
Supitcha Rungrodnimitchai ◽  
Suphatra Hiranphinyophat

In the present study, nanofibers of oxidized cellulose (OC) were prepared from dried bacterial cellulose using a mixture of nitric acid/phosphoric acid and sodium nitrite. Three types of dried bacterial cellulose were used as raw materials. The results revealed that dried sheet bacterial cellulose (DSBC) yielded 86.8% oxidized cellulose with 19.4% carboxyl content, whereas squeeze-dried bacterial cellulose (SDBC) yielded 53.3% OC with 28.6% carboxyl content, and freeze-dried bacterial cellulose (FDBC) yielded 55.6% of OC with 27.6% carboxyl content. The results revealed that OC neutralized with sodium hydroxide from SDBC showed the best swelling property among all types of OC. SDBC indicated the reduction of CFU exceeds 99.99% for gram-negative bacterium Escherichia coli ATCC 25922 and gram-positive bacterium Staphylococcus aureus ATCC 6538.


HortScience ◽  
1992 ◽  
Vol 27 (12) ◽  
pp. 1261c-1261
Author(s):  
Francisco Lopez-Gutierrez ◽  
Harrison G. Hughes ◽  
Nicholas C. Carpita

After 6 months of growth in 200,400, and 500 mm NaCl, cultured cells of Distichlis spicata showed a decreased cell volume (size) despite maintenance of turgor pressure sometimes 2-fold higher than that of the control. Tensile strength, as measured by a nitrogen gas decompression technique, showed empirically that the walls of NaCl-stressed cells were weaker than those of nonstressed cells. Breaking pressures of the walls of control cells were ≈68 ± 4 bars, while that of the walls of cells grown in 500 mm NaCl (-25 bars) were 14 ± 2 bars. The relative amount of cellulose per cell remained about constant despite salt stress. However, glucuronoarabinoxylans were more readily extractable, presumably because of a decrease in cross-linkage with phenol substances. Therefore, we suggest that cellulose microfibrils are not the only determinants that confer tensile strength to the primary cell wall, but rather subtle changes in the matrix polysaccharides are likely responsible for this event.


2021 ◽  
Vol 22 (14) ◽  
pp. 7383
Author(s):  
Joanna Jabłońska ◽  
Magdalena Onyszko ◽  
Maciej Konopacki ◽  
Adrian Augustyniak ◽  
Rafał Rakoczy ◽  
...  

Here, we designed paper sheets coated with chitosan, bacterial cellulose (nanofibers), and ZnO with boosted antibacterial and mechanical activity. We investigated the compositions, with ZnO exhibiting two different sizes/shapes: (1) rods and (2) irregular sphere-like particles. The proposed processing of bacterial cellulose resulted in the formation of nanofibers. Antimicrobial behavior was tested using E. coli ATCC® 25922™ following the ASTM E2149-13a standard. The mechanical properties of the paper sheets were measured by comparing tearing resistance, tensile strength, and bursting strength according to the ISO 5270 standard. The results showed an increased antibacterial response (assigned to the combination of chitosan and ZnO, independent of its shape and size) and boosted mechanical properties. Therefore, the proposed composition is an interesting multifunctional mixture for coatings in food packaging applications.


2014 ◽  
Vol 6 (1) ◽  
pp. 27 ◽  
Author(s):  
Desi Mustika Amaliyah

Durian (Durio zibethinus) and cempedak (Artocarpus integer) peels waste are not used by the society. The research aim is to extract pectin from durian and cempedak peels and to formulate the pectin into edible films for food packaging. The research stages were first pre-treatment of durian and cempedak peels, pectin extraction, pectin drying, and  pectin application as edible films with concentration of 0%, 5%, and 15%. Based on this research it was concluded that pectin can be extracted from durian and cempedak peels with yield result of 27.97 % and 55.58 %, respectively. Edible film obtained has  similar characteristics between raw materials cempedak and durian peels. The higher concentration of cempedak peel  pectin increased the thickness, but decreased the tensile strength and elongation at a concentration of 15%. While in edible films from durian peel pectin, the higher concentration of pectin decreased the thickness of edible film on pectin concentration of 15%, lowered tensile strength and raised the edible film elongation.Keywords: waste, durian, cempedak, pectin extraction, edible film


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2174
Author(s):  
Diana Gregor-Svetec ◽  
Mirjam Leskovšek ◽  
Blaž Leskovar ◽  
Urška Stanković Elesini ◽  
Urška Vrabič-Brodnjak

Polylactic acid (PLA) is one of the most suitable materials for 3D printing. Blending with nanoparticles improves some of its properties, broadening its application possibilities. The article presents a study of composite PLA matrix filaments with added unmodified and lignin/polymerised lignin surface-modified nanofibrillated cellulose (NFC). The influence of untreated and surface-modified NFC on morphological, mechanical, technological, infrared spectroscopic, and dynamic mechanical properties was evaluated for different groups of samples. As determined by the stereo and scanning electron microscopy, the unmodified and surface-modified NFCs with lignin and polymerised lignin were present in the form of plate-shaped agglomerates. The addition of NFC slightly reduced the filaments’ tensile strength, stretchability, and ability to absorb energy, while in contrast, the initial modulus slightly improved. By adding NFC to the PLA matrix, the bending storage modulus (E’) decreased slightly at lower temperatures, especially in the PLA samples with 3 wt% and 5 wt% NFC. When NFC was modified with lignin and polymerised lignin, an increase in E’ was noticed, especially in the glassy state.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1263
Author(s):  
David Stuart Thompson ◽  
Azharul Islam

The extensibility of synthetic polymers is routinely modulated by the addition of lower molecular weight spacing molecules known as plasticizers, and there is some evidence that water may have similar effects on plant cell walls. Furthermore, it appears that changes in wall hydration could affect wall behavior to a degree that seems likely to have physiological consequences at water potentials that many plants would experience under field conditions. Osmotica large enough to be excluded from plant cell walls and bacterial cellulose composites with other cell wall polysaccharides were used to alter their water content and to demonstrate that the relationship between water potential and degree of hydration of these materials is affected by their composition. Additionally, it was found that expansins facilitate rehydration of bacterial cellulose and cellulose composites and cause swelling of plant cell wall fragments in suspension and that these responses are also affected by polysaccharide composition. Given these observations, it seems probable that plant environmental responses include measures to regulate cell wall water content or mitigate the consequences of changes in wall hydration and that it may be possible to exploit such mechanisms to improve crop resilience.


2021 ◽  
Vol 55 (2) ◽  
pp. 331-349
Author(s):  
Hannes Orelma ◽  
Atsushi Tanaka ◽  
Maija Vuoriluoto ◽  
Alexey Khakalo ◽  
Antti Korpela

AbstractTraditional particle board can generate harmful indoor air emissions due to the volatile resin-based compounds present. This study investigated the preparation of sawdust particle board using the novel ionic liquid based fusion approach with [EMIM]OAc. The dissolution parameters were investigated using the thermal optical microscopy technique. The particle board sheets were prepared by hot pressing sawdust in the presence of ionic liquid (IL) ([EMIM]OAc) and subsequently purifying the fusion sawdust matrix from the IL with methanol. The fusion process of the sawdust particles was analysed with SEM and mechanical testing. The raw materials and the produced materials were investigated with elemental analysis, FTIR, and 13C-SS-NMR. IL fusion of the sawdust required a temperature above 150 °C, similar to the glass transition temperature (tg) of lignin. At lower temperatures, strong particle fusion was not obtained. It was observed that the sawdust/IL weight ratio was an important parameter of the fusion process, and a 1:3 weight ratio resulted in the strongest particle boards with a tensile strength of up to 10 MPa, similar to commercial particle boards. The particle fusion process was also studied with a twin-screw extruder. The extrusion enhanced the fusion of the sawdust particles by increasing dissolution of the sawdust particles, which was subsequently seen in elevated tensile strength (20 MPa). The study provides a practical view of how sawdust-based particle board can be manufactured using ionic liquid-based fusion.


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