Thermal stability of cellulose nanocrystals prepared by succinic anhydride assisted hydrolysis

2018 ◽  
Vol 663 ◽  
pp. 145-156 ◽  
Author(s):  
Agnieszka Leszczyńska ◽  
Paulina Radzik ◽  
Katarzyna Haraźna ◽  
Krzysztof Pielichowski
Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 866 ◽  
Author(s):  
Agnieszka Leszczyńska ◽  
Paulina Radzik ◽  
Ewa Szefer ◽  
Matej Mičušík ◽  
Mária Omastová ◽  
...  

The surface modification of cellulose nanocrystals (CNC) is a key intermediate step in the development of new functionalities and the tailoring of nanomaterial properties for specific applications. In the area of polymeric nanocomposites, apart from good interfacial adhesion, the high thermal stability of cellulose nanomaterial is vitally required for the stable processing and improvement of material properties. In this respect, the heterogeneous esterification of CNC with succinic anhydride was investigated in this work in order to obtain CNC with optimised surface and thermal properties. The influence of reaction parameters, such as time, temperature, and molar ratio of reagents, on the structure, morphology and thermal properties, were systematically studied over a wide range of values by DLS, FTIR, XPS, WAXD, SEM and TGA methods. It was found that the degree of surface substitution of CNC increased with the molar ratio of succinic anhydride to cellulose hydroxyl groups (SA:OH), as well as the reaction time, whilst the temperature of reaction showed a moderate effect on the degree of esterification in the range of 70–110 °C. The studies on the thermal stability of modified nanoparticles indicated that there is a critical extent of surface esterification below which only a slight decrease of the initial temperature of degradation was observed in pyrolytic and oxidative atmospheres. A significant reduction of CNC thermal stability was observed only for the longest reaction time (240 min) and the highest molar ratio of SA:OH. This illustrates the possibility of manufacturing thermally stable, succinylated, CNC by controlling the reaction conditions and the degree of esterification.


2011 ◽  
Vol 415-417 ◽  
pp. 261-264
Author(s):  
Yuan Ren ◽  
Zheng Xi ◽  
Wen Jun Gan ◽  
Liang Zhang ◽  
Jing Zhang ◽  
...  

A siloxane-containing dianhydride, succinic anhydride terminated polydimethylsiloxane (DMS-Z21) was selected to cure diglycidyl ether of bisphenol-A based epoxy resin (DGEBA). The cure kinetics and thermal properties were investigated by nonisothermal and isothermal differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA), respectively. The activation energy (Ea) of the curing reaction was obtained based on the methods of Kissinger and isothermal measurements. The results of the thermogravimetric analyses of the DGEBA/DMS-Z21 system showed that the thermal stability of the DGEBA/DMS-Z21 system was slightly higher than the DGEBA/MeTHPA system.


2020 ◽  
Vol 54 (22) ◽  
pp. 3159-3169 ◽  
Author(s):  
Ezatollah (Nima) Amini ◽  
Mehdi Tajvidi

Utilization of cellulose nanocrystals as an additive in the formulation of biocomposites made with Acrodur® resin is presented. Natural fibers/polyethylene terephthalate mats were impregnated with Acrodur® and hot-pressed into the final thickness of 3 mm after drying. Biocomposites with 2 wt.% and 5 wt.% cellulose nanocrystal (dry-basis) were also produced. The produced biocomposite panels were then tested to determine the flexural strength, flexural modulus and Izod impact strength. The results revealed that adding cellulose nanocrystal to the composite formulation increased flexural modulus significantly up to 970 MPa (17.5% increase) at a panel density of 0.5 g/cm3, while it did not significantly affect flexural strength values. A slight reduction was observed in the impact strength of the samples by adding cellulose nanocrystal. The fractured samples of impact test were observed under a scanning electron microscope. It was shown that in all cases, the fracture happened due to the failure of the fibrous system and in particular natural fibers. Thermal stability of the composites was also investigated using thermo-gravimetric analysis. It was found that adding cellulose nanocrystal slightly reduced the thermal stability of the biocomposites. Potential compatibility of cellulose nanocrystal particles with Acrodur® resin is promising and the improvement in flexural modulus can lead to the design of lighter parts for automotive applications such as door panels, headliners, and underbody shields.


Cellulose ◽  
2018 ◽  
Vol 26 (1) ◽  
pp. 507-528 ◽  
Author(s):  
Oriana M. Vanderfleet ◽  
Michael S. Reid ◽  
Julien Bras ◽  
Laurent Heux ◽  
Jazmin Godoy-Vargas ◽  
...  

2011 ◽  
Vol 391-392 ◽  
pp. 950-954 ◽  
Author(s):  
Xin Wen Peng ◽  
Jun Li Ren ◽  
Lin Xin Zhong ◽  
Yan Bo Huang ◽  
Run Cang Sun

Xylan-rich Hemicelluloses (XH) isolated from wheat straw were converted to functional biopolymers by modification using succinic anhydride (SA) as reactant without catalyst in 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid. The reaction was performed under various conditions such as different temperatures, different times, and the different amounts of SA, and the effect of reaction factors on the degree substitution (DS) of products were discussed. The product had the maximum DS of 1.80. The structure of modified hemicellulosic derivatives (MD) was actually confirmed by13C NMR spectroscopy. The thermal behavior of MD was monitored by means of thermogravimetry (TG) and differential thermal analysis (DTA), and the thermal stability of MD was lower than XH.


2012 ◽  
Vol 89 (3) ◽  
pp. 971-978 ◽  
Author(s):  
Hou-Yong Yu ◽  
Zong-Yi Qin ◽  
Yan-Nan Liu ◽  
Long Chen ◽  
Na Liu ◽  
...  

Cellulose ◽  
2012 ◽  
Vol 19 (3) ◽  
pp. 855-866 ◽  
Author(s):  
Hanieh Kargarzadeh ◽  
Ishak Ahmad ◽  
Ibrahim Abdullah ◽  
Alain Dufresne ◽  
Siti Yasmine Zainudin ◽  
...  

Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1547 ◽  
Author(s):  
Siti Zarina Zakuwan ◽  
Ishak Ahmad

Herein, hybrid k-carrageenan bio-nanocomposite films were fabricated by using two types of nanofillers, organically modified montmorillonite (OMMT), and cellulose nanocrystals (CNCs). Hybrid bio-nanocomposite films were made by casting techniques employing 4 wt% of CNCs, OMMT, and hybridized CNCs/OMMT in a 1:1 ratio. The rheological and morphological properties and thermal stability of all composites were investigated using rotational rheometry, thermogravimetry analysis, differential scanning calorimetry, field emission scanning electron microscopy, and transmission electron microscopy (TEM). The results showed that the hybrid CNC/OMMT bio-nanocomposite exhibited significantly improved properties as compared to those for the bio-nanocomposites with single fillers due to the nanosize and homogenous nanofiller dispersion in the matrix. Rheological analysis of the hybrid bio-nanocomposite showed higher dynamic shear storage modulus and complex viscosity values when compared to those for the bio-nanocomposite with individual fillers. The TEM analysis of the hybridized CNC/OMMT bio-nanocomposite revealed that more particles were packed together in the CNC network, which restricted the matrix mobility. The heat resistance and thermal stability bio-nanocomposite k-carrageenan film enhanced rapidly with the addition of hybridized CNCs/OMMT to 275 °C. The hybridized CNCs/OMMT exhibited synergistic effects due to the good affinity through interfacial interactions, resulting in the improvement of the material properties.


2019 ◽  
Vol 10 (4) ◽  
pp. 63-76
Author(s):  
Wei Keat Ng ◽  
Wen Shyang Chow ◽  
Hanafi Ismail

Cellulose nanocrystals were extracted from agricultural waste corn cob using acid hydrolysis followed by freeze drying. Poly(lactic acid)/corn cob cellulose nanocrystals (PLA/CCNC) composites were prepared using solvent casting. The properties of CCNC were characterized using transmission electron microscope (TEM), zeta potential analyzer, and thermogravimetric analyzer (TGA). The effects of CCNC on the thermal properties of PLA were examined using differential scanning calorimetry (DSC) and TGA. From the SEM and TEM results, the irregular shaped and micron-sized corn cob powder was transformed to needle-like shaped nanocellulose (aspect ratio approximately 30.80) after the acid hydrolysis process. TGA results show that the thermal stability of CCNC is higher than that of corn cob powder. The zeta potential of CCNC is −24.6 mV, which indicates there is a repulsion force between the individual CCNC and making them disperse uniformly and stable in aqueous media. DSC and TGA results show that the crystallinity and thermal stability of PLA were increased by the incorporation of CCNC. This demonstrates that the CCNC is a potential bio-nanofiller with good thermal stability and nucleating-ability for PLA.


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