Studies on the Properties of Banana Fibers-Reinforced Thermoplastic Cassava Starch Composites: Preliminary Results

2009 ◽  
Vol 87-88 ◽  
pp. 439-444 ◽  
Author(s):  
Xian Zhong Mo ◽  
Yu Xiang Zhong ◽  
Chun Qun Liang ◽  
Shu Juan Yu

Banana fibers received four treatments, namely squeezing, alkali and hydrogen peroxide treatment, washing with water, and drying. Thermoplastic starch composites was prepared with glycerol as the plasticizer, banana fiber as reinforcement and thermoplastic cassava starch as matrix. The banana fiber could increase processing torque highly, while the effects of fiber contents on peak torque at 3min was so obvious. X-ray diffractograms illustrated that with increasing fiber content, cellulose crystallinity at 22.5° gradually got stronger but starch crystallinity at 20° almost didn’t. SEM micrographs showed good dispersion and adhesion between starch and fiber. Studies in the dependence of mechanical properties of reinforced TPS on the contents of fiber that with increasing fiber content from 0 to 20phr, the initial tensile strength was trebled up to 14.46 MPa, while the elongation at break was reduced from 68 to 13%. TG mass loss curves showed that thermal stability of this composites had great improved under 500°C.

2011 ◽  
Vol 221 ◽  
pp. 586-591 ◽  
Author(s):  
Xian Zhong Mo ◽  
Yu Xiang Zhong ◽  
Jin Ying Pang ◽  
Ting Guo ◽  
Xiang Qi

As the matrix of sisal fiber, thermoplastic tapioca starch(TPS) was prepared with the mixed plasticizer, formamide and urea (mass ratio 2:1). X-ray diffractograms showed that with increasing fiber content(below 30phr), cellulose crystallinity at 22.5° gradually got stronger but starch crystallinity at 15.3°, 17.1°, 18.2°, 23.5° already disappeared, showed that this matrix still restrained the retrogradation of starch. SEM micrographs showed good dispersion and adhesion between starch and fiber. Studies in the dependence of mechanical properties of reinforced TPS on the fiber content from 0 to 30phr, the initial tensile strength was quadrupled up to the maximum 21.83MPa at 20phr fiber content, while the elongation at break was reduced from 72% to 0.44%. TG mass loss curves showed that thermal stability of this composites had great improved under 500°C.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Nanthicha Thajai ◽  
Krittameth Kiattipornpithak ◽  
Pensak Jantrawut ◽  
...  

AbstractCassava starch was blended with glycerol to prepare thermoplastic starch (TPS). Thermoplastic starch was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented polyethylene grafted maleic anhydride particles (2 μm) dispersed in the thermoplastic starch matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of polyethylene grafted maleic anhydride (121 °C) decreased to 111 °C because of the small crystal size of the polyethylene grafted maleic anhydride phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of polyethylene grafted maleic anhydride. This reaction reduced the interfacial tension between thermoplastic starch and polyethylene grafted maleic anhydride, which improved the compatibility, mechanical properties, and morphology of the blend.


2013 ◽  
Vol 747 ◽  
pp. 673-677 ◽  
Author(s):  
Worasak Phetwarotai ◽  
Duangdao Aht-Ong

Biodegradable ternary blend films of nucleated polylactide (PLA), poly (butylene adipate-co-terephthalate) (PBAT), and thermoplastic starch (TPS) with the presence of nucleating agent and compatibilizer were prepared via a twin screw extruder. The effects of compatibilizer types and starch contents on the thermal, morphological, and tensile properties of these blend films were evaluated. Two types of compatibilizer (methylene diphenyldiisocyanate (MDI) and polylactide-graft-maleic anhydride (PLA-g-MA)) were used for enhancing an interfacial adhesion of the blends, whereas TPS from tapioca starch was added as a filler at various concentrations (0 to 40 wt%). In addition, talc and PBAT acted as a nucleating agent and a flexible polymer were fixed at 1 phr and 10 wt%, respectively. The results indicated that the thermal stability of the blend films was affected from the presence of compatibilizer and TPS. In addition, the tensile properties and compatibility of PLA, PBAT, and TPS blends were improved with the addition of compatibilizer compared to uncompatibilized blend films as evidenced by SEM results. Furthermore, the blend films with MDI gave higher mechanical properties than those with PLA-g-MA at all compositions. The water absorption of the ternary blend films was evidently increased when the TPS amount was increased; in contrast, tensile strength and elongation at break (EB) of these blend films were significantly decreased.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Rihui Lin ◽  
He Li ◽  
Han Long ◽  
Jiating Su ◽  
Wenqin Huang

Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435) under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2 : 1, reaction time 4 h at 45°C, and 15% of lipase dosage. The degree of substitution (DS) reaches 0.098. Product from esterification of cassava starch with rosin acid was confirmed by FTIR spectroscopy and iodine coloration analysis. Scanning electron microscopy and X-ray diffraction analysis showed that the morphology and crystallinity of the cassava starch were largely destroyed. Thermogravimetric analysis indicated that thermal stability of rosin acid starch decreased compared with native starch.


2021 ◽  
Author(s):  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Nanthicha Thajai ◽  
Krittameth kiattipronpithak ◽  
Pensak Jantrawut ◽  
...  

Abstract Cassava starch was blended with glycerol to prepare thermoplastic starch (TPS). TPS was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented PEMAH particles (2 µm) dispersed in the TPS matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of PEMAH (121°C) decreased to 111°C because of the small crystal size of the PEMAH phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy (FTIR) confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of PEMAH. This reaction reduced the interfacial tension between TPS and PEMAH, which improved the compatibility, mechanical properties, and morphology of the blend.


2018 ◽  
Vol 152 ◽  
pp. 02007 ◽  
Author(s):  
Man Chee Lee ◽  
Seong Chun Koay ◽  
Ming Yeng Chan ◽  
Ming Meng Pang ◽  
Pui May Chou ◽  
...  

Polylactic acid (PLA) is biodegradable thermoplastic that made from renewable raw material, but its high cost limited the application. Thus, addition of natural fiber can be effectively reduced the cost of PLA. This research is utilised natural fiber extracted from durian husk to made PLA biocomposites. This paper is focus on the effect of fiber content on tensile and thermal properties of PLA/durian husk fiber (DHF) biocomposites. The results found that the tensile strength and modulus of this biocomposites increased with increase of fiber content, but the strength still lower compared to neat PLA. Then, the elongation at break of biocomposites was expected decreased at higher fiber content. The PLA/DHF biocomposites with 60 phr fiber content exhibited tensile strength of 11 MPa, but it is too brittle yet for any application. The addition of DHF caused an early thermal degradation on PLA biocomposites. Then, the thermal stability of PLA biocomposites was decreased with more fiber content.


2011 ◽  
Vol 12 (2) ◽  
pp. 131-144 ◽  
Author(s):  
Yusof Yusliza ◽  
Ahmad Zuraida

ABSTRACT : The effect of fiber content on mechanical properties and thermal stability of the cotton/albumen composites (CAC) were investigated and presented in this paper. The composites having 0%, 3%, 6%, 10%, 13 %, and 16% w/w of cotton fiber were considered.  Hands lay-up technique was used to prepare the CAC specimens and dried for 24 hours before characterised and evaluated for their mechanical performance. The structure and thermal stability of the composites were characterized by using x-ray and thermogravimetry analysis, respectively. The tensile strength and impact resistance of CAC are found maximum with the value of 8.7 MPa and 19.0 kJ/m2, respectively. Analysis on the morphological structure by SEM revealed that the mechanical properties of the composites depend on good wettability and adhesion between fiber/matrix.


Author(s):  
Lamis R. Darwish ◽  
Mohamed Tarek El-Wakad ◽  
Mahmoud Farag ◽  
Mohamed Emara

Starch based green composites have been studied as potential materials to be used in several biomedical applications. This paper explores utilizing starch based composites reinforced with pseudostem banana fibers in fabricating biodegradable maxillofacial bone plates. Corn starch plasticized by 30 wt.% glycerin and 20 wt.% distilled water was used as a matrix. The produced thermoplastic starch (TPS) matrix is reinforced with pseudostem banana fibers at different weight fractions using hot pressing at 5 MPa and 160ºC for 30 minutes. Our experimental results showed that increasing the banana fibers weight fraction progressively improved the mechanical properties reaching a maximum at 50 wt.% fibers. The improvement in the mechanical properties of starch/banana fibers composite was attributable to the strong interaction between fibers and the starch matrix, as evidenced by a series of scanning electron micrographs of the fracture surface. Furthermore, experiments investigating thermal properties and water uptake also showed that the best results are achieved at the 50 wt.% banana fibers. The experimental results show that the starch matrix-banana fiber composites satisfy the maxillofacial bone fixation requirements.


2011 ◽  
Vol 194-196 ◽  
pp. 484-487 ◽  
Author(s):  
Xian Zhong Mo ◽  
Chen Mo ◽  
Xiang Qi ◽  
Ren Huan Li

Biopolymer cassava starch(ST)-chitosan(CS)/montmorillonite(MMT) nanocomposites were prepared in which MMT was used as nanofiller and diluted acetic acid was used as solvent for dissolving and dispersing cassava starch, chitosan and MMT. XRD and TEM results indicated the formation of an exfoliated nanostructure of ST-CS/MMT nanocomposites. Mechanical properties testing revealed that at the range of the MMT content from 1wt% to 5wt%, tensile strength of the composites increased from 30MPa to 37.5MPa. But the elongation at break fall from 28% to 22% with the increasing of MMT. Obviously, MMT had an enforced effect to the composites. TGA results showed that the nano-dispersed MMT improved the thermal stability of the matrix systematically with the increasing of MMT.


2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Regina Jeziorska ◽  
Agnieszka Szadkowska ◽  
Ewa Spasowka ◽  
Aneta Lukomska ◽  
Michal Chmielarek

The effect of plasticizer (polydimethylsiloxanol) and neat (SiO2) or modified (having amine functional groups) silica (A-SiO2) on morphology, thermal, mechanical, and rheological properties of PLA/TPS blends compatibilized by maleated PLA (MPLA) was investigated. Toughened PLA/MPLA/TPS (60/10/30) blend containing 3 wt.% of plasticizer and various contents (1, 3, or 5 wt.%) of silica were prepared in a corotating twin-screw extruder. From SEM, it is clear that plasticized PLA/MPLA/TPS blend continuous porous structure is highly related to the silica content and its functionality. The results indicate that polydimethylsiloxanol enhances ductility and the initial thermal stability of the plasticized blend. DSC and DMTA analyses show that nucleation ability and reinforcing effect of A-SiO2on plasticized blend crystallization are much better than those of SiO2. Silica practically had no effect on the thermo-oxidative degradation. However, the composites with A-SiO2had better thermal stability than those with SiO2. Moreover, silica significantly improved the elongation at break.


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