Addition Of Cellulose Nanofibrils Research Articles

Biopolymer nanocomposite blends of poly(lactic acid) and polyhydroxybutyrate biopolymers reinforced with cellulose nanofibrils at low loading ratio

AbstractThis study investigated the mechanical, morphological, thermal, rheological properties, and accelerated aging performance of poly(lactic acid) (PLA)/polyhydroxybutyrate (PHB) blends with cellulose nanofibrils (CNFs) at low loading ratio. According to the obtained results, the addition of both PLA and CNFs were found to generally increase the mechanical properties of the biopolymer nanocomposites (BNCs). Morphological characterization with scanning electron microscopy (SEM) exhibited that cellular structure occurred in all the BNCs with adding both PLA and CNFs. Thermal stability of the BNCs improved with PLA and CNFs. The addition of CNFs and PLA generally increased the isotherms including Tg, Tc, and Tm according to differential scanning calorimetry (DSC), and it was found that the blends' crystallinity dropped because of a poor crystallinity of PLA. The addition of both PLA and CNFs provided an improvement on the rheological and viscoelastic properties of the neat PHB. XRD pattern of all the BNCs was found to be similar to the neat blends and the BNCs. In the accelerated weathering test, the adding PLA to neat PHB was found to provide more improvement than adding of CNFs.

Effect of cellulose nanofibrils on formation, interactions and gelation properties of chickpea protein isolate emulsion gels

Chickpea protein isolate (CPI) emulsion gels suffered from poor elasticity and loose structure, which greatly limited their application and development. This work aimed to investigate the effect of cellulose nanofibrils (CNFs) on the intermolecular interactions, protein structure, gel properties, and microstructure of CPI emulsion gels. Results showed that CNFs enhanced the hydrophobic interactions, electrostatic interactions, and hydrogen bonding of the CPI emulsion gels, and contributed to the transition of the secondary structure of CPI from α-helix to β-sheet structure. CPI-CNFs emulsion gels exhibit better textural properties, rheological properties and water holding capacity compared to CPI emulsion gels. Gel strength increased from 40.67 g to 56.26 g and hardness increased from 42.95 g to 60.67 g. Furthermore, scanning electron microscopy showed that the CPI emulsion gel structures were transformed from rough and porous to uniform and dense with the addition of CNFs. This study indicated that CNFs will help improve the properties of CPI emulsion gels with wide applications in the food field.

Fabrication of smart film based on fish gelatin incorporating phycoerythrin and cellulose nanofibrils to monitor fish freshness

Phycoerythrin (PE) extract from red algae Laver (Pyropia dentata) was used in the fabrication of a smart packaging film. The PE showed pH sensitivity, implying unique color shifts at different pH. The film colors altered from red through purple-brown to colorless with increasing pH. The smart packaging films were prepared by casting method composed of gelatin (GE), sodium alginate (SA), and cellulose nanofibrils (CNF). The films were coded as GE/SA (control), GE/SA/PE, and GE/SA/CNF/PE. The thickness of the films ranged from 0.24 ± 0.02 mm to 0.33 ± 0.01 mm. The mechanical properties tensile strength (TS) (12.24 ± 0.30 MPa to 17.65 ± 0.33 MPa) and elongation at break (EAB) (79.34% ± 1.02%–93.36% ± 0.69%) significantly increased after addition of CNF. The synthesized films showed water contact angle ranged from 84.55 ± 2.12 to 69.41 ± 1.21, suggesting that films were hydrophobic. The Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis demonstrated strong interaction among PE, CNF, and biopolymers. The film with GE/SA/CNF/PE exhibited higher thermal stability compared with control film. Then, the films were applied for checking real time application for the freshness of salmon fish. The significant color change of the film occurred and the number of bacterial colony and TVB-N were increased from 3.81 Log CFU/g to 6.94 Log CFU/g and from 4.78 mg/100 g to 32.27 mg/100 g after incubation for 48 h. Therefore, the film with PE and CNF was intended as an excellent candidate for smart packaging film.

Enhancement of mechanical and thermal properties of UV‐curable wood coatings by cellulose nanofibrils and carboxylated organo‐montmorillonite

AbstractIn this study, the impact of incorporating cellulose nanofibrils (CNF) and carboxylated organo‐montmorillonite (OMMT), separately or in combination, into a UV‐curable wood coating was evaluated for performance enhancement. This study investigated the influence of nanoparticle loading percentage on the mechanical properties and thermal behavior of the coating, as well as the surface properties of digitally printed decorative wood‐based panels. The results indicated that the addition of CNF or OMMT increased the viscosity of the polymer solutions. Although CNF randomly oriented within the matrices, OMMT adhered to the surface of the polymer matrix. Chemical crosslinking was observed between CNF/OMMT and the coating. The addition of CNF and OMMT improved the thermal stability of the neat UV curing coating. The tensile strength of nanocomposite films with a 6 wt% loading of CNF increased significantly from 7.63 MPa to 12.73 MPa compared to pure films. The reinforcing effect of CNF on the tensile performance was significantly better than that of OMMT. Adding CNF to the matte coating slightly improved the clarity of the printed decorative panels. When CNF and OMMT were added together in the coating, there was a synergistic enhancement in the low gloss and high pencil hardness of the panels.Highlights Both CNF and OMMT were chosen to achieve performance improvements A simple filling method was adopted for preparation of reinforced coating The nanocomposite films exhibited fine thermal and mechanical properties The better integrated property was obtained from the C + CNF3 + OMMT0.8 sample The physicochemical interaction of nanofiller with polymer molecule existed

Integration of wood-based components – Cellulose nanofibrils and tannic acid - into a poly(vinyl alcohol) matrix to improve functional properties

Poly(vinyl alcohol) (PVA) biocomposite films reinforced with cellulose nanofibrils (CNF) and biologically active tannic acid (TA) were prepared. The influence of different concentrations of CNF and TA in the PVA polymer matrix was investigated in terms of mechanical properties, thermal properties and hydrophobicity improvement of the prepared films. The results showed that in all cases the addition of CNF and TA improved the values of tensile strength and elastic modulus. The PVA film with 10 % CNF exhibited a 30 % higher tensile strength, and the three-component PVA film with 2 % CNF and 10 % TA (P2C10T) exhibited a 40 % higher tensile strength compared to the neat PVA film. The thermal properties (Tg, Tonset) of the PVA biocomposite films were greatly improved, with a significant effect observed for the three-component PVA films. The Tg of the PVA film with 10 % CNF and 10 % TA was 87 °C, 12 °C higher than that of the neat PVA film. For three-component PVA biocomposites with 4 % and 6 % CNF and with all weight percentages of TA, the Tonset shifted to a higher temperature range by about 30 °C compared to the neat PVA film. The PVA film with 2 % CNF and 10 % TA exhibited about a 20° higher contact angle than the neat PVA film. Moreover, the addition of both fillers to the PVA matrix resulted in PVA biocomposites with lower water absorption. PVA film with 10 % TA absorbed about 90 % less water and PVA film with 10 % CNF and 10 % TA absorbed about 80 % less water than the neat PVA film after the films were soaked in water for one hour. The better properties of the composite films produced are due to hydrogen and ester bonds between the components of the composite, which was confirmed by FT-IR spectroscopy. Antioxidant effective films were also obtained due to the biologically active TA to the PVA and PVA/CNF systems.

Thermal properties of cellulose nanofibrils and nickel-titanium alloy-reinforced sustainable smart composites

ABSTRACT The study focused on the synergistic effect of cellulose nanofibrils (CNFs) as a lignocellulosic bionanomaterial and nickel-titanium (NiTi) alloy as a shape memory smart metallic material reinforcer on the thermal properties of sustainable smart composites. The casting process was used to produce composites with CNF loadings of 1%, 3%, and 5% and NiTi loadings of 3% into epoxy resin. Thermal properties were evaluated using thermogravimetric (TGA), derivative thermogravimetric (DTG), differential scanning calorimetry (DSC), and dynamic mechanical thermal (DMTA) analysis. The TGA results revealed that the CNF/NiTi-reinforced groups have considerable higher degradation temperatures and thermal stability than the control group. Also, at 800°C, CNF/NiTi-reinforced groups had a higher residual content than the control group. DTG results showed that the addition of CNFs decreased the degradation speed. Although the NiTi loading was constant, it was determined that the addition of CNFs increases the storage modulus (E′), loss modulus (E″), tan delta (Tan δ), and glass transition temperature (Tg). Overall, it can be concluded that CNF/NiTi-reinforced composites indicated significantly improved thermal stability, decomposition temperature, residual content, elastic, and viscous properties. These smart composites can be used for advanced material applications requiring thermal stability.

Influence of formic acid esterified cellulose nanofibrils on compressive strength, resilience and thermal stability of polyvinyl alcohol-xylan hydrogel

Having competitive compressive strength and resilience as well as biocompatibility simultaneously still remains a challenge for composite hydrogels, which is critical if they are aimed for use as functional biomaterials. In the present work, a facile and green method was designed for producing a composite hydrogel based on polyvinyl alcohol (PVA) and xylan with sodium tri-metaphosphate (STMP) as cross-linker, aiming to specially enhance its compressive properties with the aid of eco-friendly produced formic acid esterified cellulose nanofibrils (CNFs). The CNF addition caused a compressive strength decrease of the hydrogels, although the values (2.34–4.57 MPa at a compressive strain of 70 %) were still at a high level among the reported PVA (or polysaccharide) based hydrogels so far. However, the compressive resilience of the hydrogels was enhanced significantly by the CNF addition, with maximal compressive strength retention of 88.49 % and 99.67 % in height recovery after 1000 compression cycles at a strain of 30 %, which reflects the significant influence of CNFs on the compressive recovery ability of the hydrogel. All materials used in the present work are naturally non-toxic with good biocompatible, which makes the synthesized hydrogels with great potential in biomedical applications, e.g., soft-tissue engineering.

Preparation and Characterization of Cellulose Nanofibril-Waterborne Polyurethane Composite Films

To improve the performance of polyurethane films, small amounts of cellulose nanofibrils (CNF) were physically blended with a waterborne polyurethane (WPU) emulsion, and then CNF/WPU composite films were prepared by cast-coating and drying. The particle size of the emulsions and the chemical structure, micromorphology, thermal stability, mechanical properties, and water resistance of the composite films were characterized using a Malvern laser particle size analyzer, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), an electronic strength machine, water contact angle analysis (WCA), and water absorption tests, respectively. The results showed that at a low CNF content of 0.3 wt%, the particle size of the WPU emulsion and chemical structure of the film did not change significantly. In addition, the tensile strength of the composite film increased by up to 108% compared to the neat WPU film, and the thermal stability and water resistance were slightly improved. The addition of CNF greatly enhanced the tensile strength while maintaining the other original properties of the WPU film, which may greatly improve the service life and tear resistance of commercial coatings in the future.

Effect of Cellulose Nanofibrils on the Physical Properties and Frost Resistance of Pervious Concrete.

Pervious concrete has good water permeability and, if used in construction, it can alleviate the heat island effect. However, its low strength and poor durability are major obstacles to its use. This study shows that nano-reinforced pervious concrete created by incorporating cellulose nanofibrils (CNFs) can improve the physical properties and increase the durability of pervious concrete. CNFs were added to the concrete mix in proportions ranging from 0.05% to 0.2% by weight of binder. The additions were found to alter matrix rheology. The hydration kinetics of matrix with differing CNF contents were compared and analyzed. The experimental results show the addition of CNFs delayed peak heat flow and maximum cumulative heat. The 28 d compressive strength of pervious concrete increased by up to 26.5% and 28 d flexural strength by up to 25.8% with the addition of 0.05-0.2% CNFs. Addition of 0.1% and 0.2% CNFs increased water permeability. Addition of 0.05-0.15% CNFs decreased mass loss by 73.2-83.7% after 150 freeze-thaw cycles, which corresponded to an increase in frost resistance. Denser matrices and stronger interfacial transition zones were observed using scanning electron microscopy when 0.05-0.2% CNFs were added.

Smart pH‐sensitive films based on biomaterials: Preparation from soy protein with hybrid fillers of CuO nanorods, cellulose nanofibrils, and Clitoria ternatea anthocyanin

AbstractBackgroundThe environmental concern about plastic consumption always rises the need for alternate materials. Plastics being widely employed in the food packaging and hence highly demands such alternatives. The toxicity and pollution produced by the conventional petroleum‐based plastics can be reduced by the usage of bioplastics. The area of food packaging using various biopolymer composites has grown much and is developing new materials by incorporating various nanofillers, especially based on green synthesis approach. This study focuses on the usage of soy protein isolate as a matrix for such films and uses copper nanomaterials and cellulose as reinforcing agent.ResultsAn active and intelligent bio nanocomposite thin film based on soy protein isolate (SPI) was prepared. Copper oxide nanorods(CuONRs) were synthesised from ascorbic acid and honey, cellulose nanofibrils (CNF) were extracted from the Acasiacaesia using steam explosion technique and anthocyanin was extracted from Clitoria ternatea flower (CTE). The effect of the addition of CuONR (5%, 10%), CNF (10%), and CTE (7%) on the physiomechanical, barrier, antibacterial, and antioxidant properties of the films was investigated. SEM showed uniform distribution of CuONR/CNF/CTE in the SPI matrix.ConclusionThe addition of CuO and CNF was found to effectively increase the mechanical property, thermal stability, and decrease the moisture content percentage of the films. In contrast, the addition of CTE made the film pH‐sensitive. SPI‐CuONR/CNF/CTE films showed good antioxidants and antibacterial properties. Fabricated film could act both as a pH sensor for detecting the evolution of acidic and basic gases and as active packaging material to extend the shelf life of food materials.

Extraction of cellulose nanofibrils from Ficus natalensis barkcloth and utilization in preparation of antimicrobial bio-nanocomposite films for possible food packaging applications

Recently, nanosized cellulose materials preparation has been extensively increased from the sources of sustainable materials and utilization in various functional applications as nanofillers. Cellulose nanofibrils (CNF) extraction through green bio-based materials featured as promising interest in the field of science. In this research, cellulose nanofibrils were extracted from a cellulose rich biomass Ficus natalensis barkcloth. Furthermore, extracted cellulose nanofibrils and Zinc oxide nanoparticles (ZnONPs) were mixed and casted to posterior analysis of formed sodium carboxymethyl cellulose (CMC) film at various concentrations of CNF (1 wt%, 5 wt%, 8 wt%, and 12 wt%) and fixed amount of ZnONPs (0.5wt%) based on CMC weight. Results revealed that CNF was smoothly distributed in the polymer matrix to form even and flexible films indicating the cellulose nanofibrils and zinc oxide are highly compatible with the CMC. Similarly, the water solubility percentage (WVP) of CMC film was low at lower content of CNF, and increased with the increase of CNF percentage. Addition of CNF and ZnONPs in nanocomposite films improved the thermal stability values and antibacterial activities of CMC films. Thus on the basis of various tremendous performance, this study showed that F.natalensis barkcloth could be considered as an alternative source of cellulose nanofibrils. Similarly, the prepared nanocomposite films can have potential application in packaging films for the extension of shelf life of fresh and minimally processed fruits and vegetables.

Biopolymer nanocomposites of polyhydroxybutyrate and cellulose nanofibrils: Effects of cellulose nanofibril loading levels

In this paper, the effect of cellulose nanofibrils (CNFs) loading levels on the conventional and dynamic mechanical, morphological, thermal and rheological properties of the polyhydroxybutyrate (PHB) biopolymers were studied. According to the results, adding CNFs from 1% to 20% generally didn’t provide any improvement in the flexural, tensile and izod impact strength attributable to void formation and pulling out and agglomeration of nanofibrils in the matrix, which was observed during morphological characterization, however adding CNFs substantially increased both flexural and tensile modulus of elasticity. Thermal analysis showed that adding CNFs generally decreased degradation at high temperatures of the biopolymer nanocomposites (BNCs) The addition of CNFs at 1, 10 and 20% increased the E' and E'' of neat PHB but the other loadings decreased them, and tan delta increased with CNF loadings of 3, 5, 10 and 20%, and finally adding CNFs didn’t change the rheological behavior of the composites.

Superelastic and flexible 3D printed waterborne polyurethane/cellulose nanofibrils structures

Waterborne polyurethane (WPU) is a type of environmental-friendly aqueous suspension that has been widely used in varied applications. However, it remains a challenge to use WPU for three-dimensional structures by additive manufacturing due to its unsatisfied rheological properties. In this study, we developed an in-situ synthesis method to modify WPU (WPUCNF) by using cellulose nanofibrils (CNF) in order to enhance its printability. The addition of CNF during emulsification reduced the WPU nanoparticles size as well as increased the suspension viscosity. To further improve the printability, additional CNFs were added as rheological modifiers. After dewatering the suspension, WPUCNF/CNF composite inks showed excellent printability, as illustrated by the printed structures of various shapes such as honeycomb, woodpile, or human ear. For these samples, heights over 10 mm could be printed with good shape fidelity at the ink concentration of as low as 2.8–7.4%, significantly lower than previously reported WPU ink for 3D printing (~20–30%). The 3D printed structure can absorb 17–37% of water due to the presence of hygroscopic salt CaCl2, and demonstrated high flexibility and withstood over 20 compressive cycles. This versatile WPUCNF/CNF ink can be adapted for designing hierarchical porous 3D structures with broad emerging applications in the biomaterials field.

Influence of Lactic Acid Surface Modification of Cellulose Nanofibrils on the Properties of Cellulose Nanofibril Films and Cellulose Nanofibril-Poly(lactic acid) Composites.

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.

Addition of wheat straw nanofibrils to improve the mechanical and barrier properties of cassava starch–based bionanocomposites

Cellulose nanofibrils (CNFs) were obtained from wheat straw, and different concentrations (0 %, 10 %, 20 %, 30 % and 50 %) of the CNFs were incorporated into cassava starch-based films. Thirty passages through a microfibrillator allowed us to obtain well-dispersed CNFs with reduced thickness (34.26 nm). The addition of CNFs promoted an average increase in tensile strength values on the order of 126.69 %. The treatments with higher CNF addition percentages (30 % and 50 %) presented higher Young's modulus values (566.68 and 585.72 MPa, respectively), which indicates an increase in stiffness. The elongation and puncture force decreased with the addition of CNFs, presenting average reductions of 83.72 % and 56.66 %, respectively. A significant decrease in water vapour permeability was observed for the treatments with higher percentages of CNFs added, with a drop from 2.15 × 10−6 in the control film to 1.39 × 10−6 g mm/KPa−1 day−1 m2 in the film with the maximum addition percentage. The contact angle values increased from 43.45° in the control film to 68.66° in the sample with the maximum CNF concentration. The lower hydrophilicity of the treatments with 30 % and 50 % CNF additions is evidenced by the lower values presented for the Cobb test (99.84 and 99.31 g m2), polar surface free energy (0.41 and 0.19 mN m-1) and polarity (0.01 and 0.007). In these treatments, there were stronger interactions between the CNF and starch molecules. Thus, the addition of 30–50 % wheat straw CNFs is recommended to strengthen the structure and improve the barrier properties of cassava starch-based films.

Effects of ligno– and delignified– cellulose nanofibrils on the performance of cement-based materials

Abstract This article presents an investigation into the effects of lignocellulose nanofibrils (LCNF) and delignified cellulose nanofibrils (DCNF) on the hydration, microstructure, and mechanical properties of cement paste. The effects of various fine contents and dosages of the cellulose nanofibrils (CNF) additions on the properties of cement paste are presented in this article. Nearly all the CNF containing batches were observed to have an accelerated cement hydration reaction within the first 30 h. However, after 80 h of hydration, the CNF additions no longer exhibited any significant effect on the degree of hydration. The cement paste batches with LCNF were observed to have improved workability compared to those with DCNF. It was further observed that the compressive and flexural strengths of the cement paste can be increased up to 20% and 111%, respectively, by the addition of CNF. Both LCNF and DCNF were found to reduce the amounts of ettringite and portlandite in the hydrated cement paste. The ideal fine content of CNF to achieve both microstructural and mechanical performance enhancement was observed to be around 75%. The experimental findings presented in this article indicate that LCNFs with low fine content (60–75%) would be a more desirable and potentially more economical additive for concrete production compared to the DCNFs with high fine contents.

Cellulose nanofibrils reinforced PBAT/TPS blends: Mechanical and rheological properties

Poly(butylene adipate-Co-terephthalate)/thermoplasticized starch PBAT/TPS blends are among the most produced biodegradable plastic for wide application packaging, sharing more than 20% of the global production capacity of bioplastics. However, this class of material suffers from poor mechanical strength in comparison of neat PBAT, especially when the TPS content exceeds 30 wt%. Aiming at enhancing the mechanical performance of PBAT/TPS blends while maintaining relatively high TPS content, cellulose nanofibrils (CNFs) was incorporated into the TPS phase using twin screw extrusion. The effects of CNFs content on the microstructure, mechanical properties, melt-rheology and humidity absorption were investigated. An enhancement in the tensile strength and modulus was noted with the inclusion of CNFs, with optimal performance attained at 8 wt% of CNFs. A narrowing in the distribution of the TPS nodules within the PBAT matrix was also observed with the addition of CNFs, which is expected to be on the origin of the main evolution in the mechanical, rheological and humidity observed. Because of the availability of CNFs, biodegradability and facile processability, the ternary PBAT-TPS-CNFs blends might contribute to improve the performance of this class of biodegradable bioplastic.

Cellulose nanofibrils with and without nanosilica for the performance enhancement of Portland cement systems

This article presents a comprehensive investigation on the effects of pure cellulose nanofibrils (CNF) and nanosilica containing CNF on the performance of ordinary portland cement (OPC) paste. The effects of CNFs on cement paste rheology, hydration, microscopic phase formation, compressive strength, and fracture parameters were monitored. Sol-gel method was used to synthesis nanosilica particles within CNF slurry. The effects of CNF on cement hydration was found to be dependent on the water to cement ratio (w/c). Specifically, CNFs accelerated the early age cement hydration at 0.35 w/c, but this acceleration effect was not prominent for 0.45 w/c. Such w/c dependent effect was attributed to the negatively charged hydroxyl and carboxyl surface sites of CNFs which can bind alkali ions or cement particles. The concentration of alkali ions in cement pore solution depends on the w/c and hence, resulting the w/c dependent effects of CNF. The colloidal stability of CNF was found to improve due to the addition of nanosilica particles. Addition of CNF was found to increase the flexural strength of cement paste up to 75%. The effects of CNF addition on the compressive strength of cement paste matrix was negligible.

In-situ modification of low molar ratio urea–formaldehyde resins with cellulose nanofibrils for plywood

This study describes the in-situ modification of low molar ratio urea–formaldehyde (UF) resins with cellulose nanofibrils (CNFs) to improve the poor performance of resins synthesized with different methods (Synth 1 and Synth 2) when adding second urea. UF resins were in-situ modified with CNFs dissolved in a mixture of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) during the alkaline reaction step. Results showed that CNF addition enhanced the resin properties, such as shorter gelation time, faster curing rates at low activation energy, higher tensile shear strength (TSS), and lower formaldehyde emission (FE), compared to those of neat resins. The dry and wet TSS values of plywood bonded with UF resins modified with 3% CNFs synthesized using Synth 2 increased by 30% and 42%, respectively, and the FE value was decreased by 22% and 42%, respectively. These results reveal that in-situ modified UF resins with CNFs showed better performance than neat UF resins and that Synth 2 was more favorable than Synth 1.

Microparticles obtained by spray-drying technique containing ginger essential oil with the addition of cellulose nanofibrils extracted from the ginger vegetable fiber

The encapsulation capacity and the polymer blends containing gum Arabic (GA), inulin (IN), and cellulose nanofibrils ginger (CNFG), extracted from the fibrous ginger residues, for the microencapsulation of ginger essential oil by spray-drying technique were evaluated in this study. The addition of CNFG improved the emulsifying properties of the formulations, with an increase in Newtonian viscosity (μ); however, the partial substitution of GA by IN decreased the viscosity. The higher IN levels increased the emulsion droplets in the formulations with and without the addition of CNFG. In addition, the emulsion droplets with smaller size resulted in the formation of pulverized droplets with smaller diameter. The presence of CNFG in the polymer blends exhibited similar instantaneization times and provided greater oil retention of ginger essential oil by spray drying. The oil retention in the formulation containing GA and CNFG was 12.23% higher than the formulation containing only GA. Changes in the retention of the compounds of pure and microencapsulated ginger essential oil were observed by GC-MS, all six major components remained in the final product, however with some variations on the encapsulated essential oil profile.