Effects of Different Pretreatments of Wood Fiber on Mechanical Properties of Biodegradable Composite

2010 ◽  
Vol 150-151 ◽  
pp. 1438-1443
Author(s):  
Yi Qiang Wu ◽  
Zhi Yong Qin ◽  
Yan Qing ◽  
Xin Gong Li

Biodegradable composites of polylactic acid reinforced with wood fiber were fabricated by using twin screw extruder followed by the injection molding machine. The effects of different pretreatments of wood on mechanical properties of the biodegradable composite were discussed. The nature of composites were also examined through scanning electron microscope and Infrared Spectrum Analysis, the results reveal that both acid and stearic acid could be used as effective surface modifier for wood fiber/polylactic acid system, the composite system by adding Benzoic acid, the tensile strength has improved greatly, and about stearic acid composite system, the impact strength has improved significantly; After alkali treatment, coupling agent treatment and combination of alkali treatment and coupling agent treatment, and the use of alkali treatment and the coupling agent treatment is the best, follow by alkali treatment.

2019 ◽  
Vol 944 ◽  
pp. 509-514 ◽  
Author(s):  
Shan Shan Liu ◽  
He Yi Ge ◽  
Yu Zou ◽  
Juan Chen

Maleic anhydride grafted polypropylene compatibilizer (MAPP) and chitosan (CS) were mixed and used as a compound coupling agent to modify the PP matrix. 5 wt% NaOH and 10 wt% NaOH aqueous solution were used to treat corn stalk fiber (CSF), respectively. The effect of the complex coupling agent and the alkali treatment on the mechanical properties of CSF/PP composite was investigated. Morphological observation of the fracture surfaces was accepted to confirm CSF dispersion and wetting with the help of SEM. The results of the water absorption further demonstrated the binding of the interface between the CSF and the PP matrix. The wetting of the CSF in the PP was improved with the addition of the complex compatibilizer (5% MAPP + 5% CS). The formation of chemical bonding between the fiber and the matrix resulted in enhancing the interfacial compatibility between them. Compared with the pure PP, the flexural strength of 15-UT-5MAPPCS (63.14 MPa) and 15-UT-5MAPPCS (69.35 MPa) increased by 22.5% and 34.5%, respectively. The complex compatibilizer can replace alkaline treatment process to improve the mechanical properties of the composite.


2012 ◽  
Vol 200 ◽  
pp. 321-324 ◽  
Author(s):  
Zhao Xia Wang ◽  
De Gao ◽  
Wen Cai Xu

Mechanical properties of the calcium-plastic composite have a great influence on the containers. The main factors affecting the mechanical properties are the process and material formulations. This paper mainly describes its impact of the addition of coupling agent. Under the usage of analysis of variance on single factor experiment, the mechanical properties of the calcium carbonate-plastic composite with three different coupling agents (silane, titanate and aluminate) were studied in the same test conditions. The results show that: The type and quantity of the coupling agent effect a lot on the mechanical properties of the composite. The silane coupling agent is the most suitable for calcium carbonate-plastic composite packaging materials, and the compatibility of calcium carbonate and polyethylene can be improved. When the silane coupling agent was at a 2.25 wt. % concentration, the tensile and flexural strength were improved obviously, especially the tensile strength increased by 23.24%, but the impact strength improved slightly.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Germán A. Arboleda ◽  
Camilo E. Montilla ◽  
Héctor S. Villada ◽  
Giovanni A. Varona

A flexible film was obtained from a blend of cassava thermoplastic starch and polylactic acid, using maleic anhydride as coupling agent. For this, an experimental design with three factors was used: polylactic acid content, coupling agent content, and temperature profile of the blown extrusion. It was found that the three factors generated significant differences on the response variables of tensile mechanical properties individually as in their triple interaction. Differential scanning calorimetry (DSC) was used by understanding the behavior of thermal properties of TPS/PLA blends with and without coupling agent, finding similar results between both. From this, the combination with 28% polylactic acid, 0.87% coupling agent, and 155.75°C temperature profile permitted the obtaining of a material with outstanding mechanical properties and offered advantages from the economic point of view.


2018 ◽  
Vol 38 (2) ◽  
pp. 157-166 ◽  
Author(s):  
Jian Wang ◽  
Jie Dong ◽  
Jianwei Zhang ◽  
Baodong Zhu ◽  
Dongling Cui

Abstract This work aimed to study the effects of different surface treatments on the morphologies and thermo-mechanical properties of the bamboo flour/polypropylene (BF/PP) composites, which were prepared by melt blending with 15 wt% of filler load. The BF was first pretreated with 10 wt% sodium hydroxide (NaOH) solutions for 4 h, after which the pre-treated BF was modified by stearic acid and silane. The chemical structure of the treated BF fibers was characterized through Fourier transform infrared spectroscopy (FTIR), and the results showed that alkali treatment efficiently removed hemicellulose, lignin, and pectin. Moreover, stearic acid and silane were successfully introduced to the BF surface through chemical bonding. The changes in heat stability of BF investigated by thermogravimetric analysis (TGA) revealed that the presence of treatment contributes to a better thermal stability for BF fibers. In addition, the scanning electron microscopy (SEM) observation of BF/PP composites displayed not only better dispersion of treated-BF in the polypropylene (PP) matrix, but also improved fiber-matrix interfacial compatibility, especially when silane treatment was used. Accordingly, the mechanical properties improved significantly in the presence of treated-BF.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Usman Saeed ◽  
Sami Ullah Rathur ◽  
Hamad AlTuraif ◽  
Hisham Bamufleh

The nanocellulose fibril produced by using natural sources can be used in developing sustainable and green products. The useful features of nanocellulose fibril can include valuable physical properties, appropriate surface chemistry, low toxicity, and biocompatibility. The study presented shows the use of polylactic acid with five different percentages of nanocellulose fibril and the use of 3% maleic anhydride as a coupling agent. The maleic anhydride acts as coupling agent which improves the thermochemical and thermomechanical characteristics of the end product. The addition of 3% maleic anhydride as coupling agent with 10% nanocellulose fibril improved the impact strength up to 14.3%, elastic modulus up to 40.6%, and tensile strength up to 30.1%. Furthermore, the dynamic mechanical analysis result indicates that the inclusion of maleic anhydride improved the toughness by reducing the tan δ peak and increases the storage modulus. Finally, the scanning electron micrograph shows that the interfacial compatibility between nanocellulose fibril and polylactic acid matrix is improved with the addition of maleic anhydride.


Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 976 ◽  
Author(s):  
Teng-Chun Yang

Wood fiber-reinforced polylactic acid (PLA) composites (WFRPCs) were used as a filament to manufacture the unidirectional WFRPC components by means of fused deposition modeling (FDM). The physico-mechanical properties of the WFRPC components printed at different extrusion temperatures (200, 210, 220, and 230 °C) were determined. The results revealed that most of the physical properties (moisture content, surface roughness, water absorption rate, and thickness swelling rate) of the printed WFRPC component were not significantly influenced by extrusion temperature, while its density and color difference increased as the extrusion temperature increased. Additionally, the tensile and flexural properties of the FDM-printed WFRPC component decreased when the extrusion temperature was more than 200 °C, whereas the compressive strength and internal bond strength increased by 15.1% and 24.3%, respectively, when the extrusion temperature was increased from 200 to 230 °C. Furthermore, scanning electronic microscopy (SEM) demonstrated that the fracture surface of the tensile component printed at a higher extrusion temperature exhibited a better compatibility at fiber/PLA interfaces and good adhesion between the extruded filament segments. These results indicate that the FDM printing process using different extrusion temperatures has a substantial impact on the surface color, density, and mechanical properties of the printed WFRPC component.


2008 ◽  
Vol 27 (16-17) ◽  
pp. 1679-1687 ◽  
Author(s):  
Amir Nourbakhsh ◽  
Bouhuslav V. Kokta ◽  
Alireza Ashori ◽  
Ahmad Jahan-Latibari

2013 ◽  
Vol 781-784 ◽  
pp. 390-394
Author(s):  
Xiao Li Song ◽  
Ying Chen ◽  
Yu Zhi Xu ◽  
Chun Peng Wang

Polyacrylate microsphere with different core/shell ratio (mass ratio) were prepared by semi-continuous seed emulsion copolymerization using butyl acrylate (BA) and methyl methacrylate (MMA) as main monomers,which were used to toughen polylactic acid (PLA) after drying. The effect of core/shell ratio of polyacrylate toughening agent (ACR) on mechanical properties of PLA was studied. The results showed that when adding 8wt%ACR, the impact strength and elongation at break of PLA were both first increased and then decreased as increasing of core/shell ratio, while the tensile strength loss of PLA was little changed. It is found that the impact strength was increased about 24% than that of neat PLA as well as the elongation at break was increased from 2% to 12% when the ratio was 7/3, which was the best ratio.


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