Effect of Processing Conditions on the Mechanical and Morphological Properties of Composites Reinforced by Natural Fibres

Author(s):  
Abouelkacem Qaiss ◽  
Rachid Bouhfid ◽  
Hamid Essabir
2020 ◽  
pp. 152808372093419 ◽  
Author(s):  
Hilal Olcay ◽  
Emine Dilara Kocak

Recently, due to environmental concerns and dependence on depleted resources, the use of renewable resources has become important in the preparation of various industrial materials. The use of natural fibers instead of petroleum-based synthetic fibers traditionally used in the production of composite materials provides many advantages in terms of both environmental and cost. The utilization of agricultural wastes as natural fibers also contributes significantly to the reduction and reuse of wastes, which is one of the objectives of sustainable development. In this study, artichoke stem waste fibers reinforced polyurethane foam composites were obtained. The fibers were treated with alkaline surface treatment at different concentrations (5% and 10%) of sodium hydroxide (NaOH) and durations (5, 10 and 15 min). The optimal alkali method was determined and applied to the fibers and its effect on composites was also investigated. Treated and untreated fibers were combined with polyurethane (PU) matrix at different reinforcement ratios (5, 10, 15 and 20%) to produce bio-fiber based composites. Depending on these reinforcement rates and alkali treatment, the mechanical properties of composites such as strength, elongation and modulus were investigated. The composites, which have the best mechanical properties, were selected and these composites were evaluated in terms of thermal and sound insulation with considering their morphological properties. It has been determined that artichoke stem waste fibers can provide good mechanical, thermal and sound insulation properties in the composites, and thus it has been found that great advantages can be achieved in terms of cost and ecology.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
S. Arun ◽  
Mrutyunjay Maharana ◽  
S. Kanagaraj

The reinforcement of epoxy by MWCNTs is done to obtain the required properties of composites. However, the homogeneous dispersion of MWCNTs in epoxy is a critical problem. Hence, an attempt is made to optimize the processing conditions for dispersing the MWCNTs in epoxy by solvent dispersion technique. The epoxy/MWCNTs mixture was prepared using three methods: (1) magnetic stirring at 55°C, (2) hot air oven process at 55°C, and (3) vacuum oven process at room temperature. The nanocomposites having 0.1 and 0.2 wt.% of MWCNTs were prepared, for each method. The mechanical properties of nanocomposites were studied as per ASTM-D695, and the thermal conductivity was measured using KD2 probe. It is observed that the compressive strength, Young’s modulus, and thermal conductivity of 0.2 wt.% of MWCNTs prepared by vacuum oven method were found to be enhanced by 39.4, 10.7, and 59.2%, respectively, compared to those of pure epoxy. Though the properties of nanocomposites were increased with MWCNTs’ concentration irrespective of the processing techniques, the vacuum-processed sample showed the most enhanced properties compared to any other method. It is concluded that a unique method for the dispersion of MWCNTs in epoxy is the solvent dispersion technique with vacuum drying process.


2011 ◽  
Vol 332-334 ◽  
pp. 1659-1665
Author(s):  
Song Mei Bi ◽  
Jun Hong ◽  
Chang Liu Chu

The effect of molding temperature, pressure, packing time and cooling methods on the properties of ramie roving reinforced polypropylene composites was mainly investigated in this paper. We used moulding process to prepare the ramie fiber/PP (Polypropylene) composites with the ramie roving as the reinforcement which were loosed into a single fiber state in the case of without affecting the fiber’s longitudinal straightness, and then investigated the influence of processing conditions to the mechanical properties of composites. With the DSC (Differential Scanning Calorimetry), the effect of cooling conditions on the crystallization of composites was also discussed. The result shows that taking ramie roving as the reinforcement will improve the infiltration properties of the PP matrix to ramie fibers, the reason is that ramie fibers have good orientation and it is loosely arranged in the ramie roving , all of these are benefit to form a good interfacial bonding between fibre and PP resin. Different processing conditions have great impact on the mechanical properties of composites. And the samples gained the best merchanical properties when the process conditions such as molding temperature, pressure, packing time are selected as 165°C, 8MPa, 10min. When the composites cooled together with the heating plate, its melting enthalpy is the highest and the crystallization properties is better than other cooling methods such as home temperature cooling and quickly water-cooling, and its tensile properties is the best.


2019 ◽  
Vol 383 (1) ◽  
pp. 1800049 ◽  
Author(s):  
Thatiana Cristina Pereira de Macedo ◽  
Juciklécia da Silva Reinaldo ◽  
Laurenice Martins Pereira ◽  
José Kaio Max Alves do Rêgo ◽  
Marcelo Massayoshi Ueki ◽  
...  

2019 ◽  
Vol 38 (1-2) ◽  
pp. 3-14 ◽  
Author(s):  
E Cusson ◽  
AH Akbarzadeh ◽  
D Therriault ◽  
D Rodrigue

Uniform foams (UF) and density graded foams (DGF) were produced by using similar or different temperatures on both sides of a compression molding system. The samples were produced using linear low density polyethylene as the matrix and activated azodicarbonamide as the chemical blowing agent. Morphological properties of the produced samples were analyzed via scanning electron microscopy to relate them to their mechanical properties. In particular, flexural and impact properties are reported for samples produced under a range of temperatures (140–200°C) and blowing agent concentration (0.7–1.0 wt%). The experimental results showed that a significant difference can be obtained in flexural modulus (up to 17%) and impact strength (up to 48%) depending on the side the stress is applied on. In all cases, the DGF showed better mechanical responses than UF of similar relative density for the range of conditions tested.


2017 ◽  
Vol 753 ◽  
pp. 50-59 ◽  
Author(s):  
Qiu Hong Mu ◽  
Dan Peng ◽  
Feng Wang ◽  
Wei Ju ◽  
Fang Zhi Zhang

Octavinyl polyhedral oligomeric silsesquioxane (POSS) were used to hybrid with polysiloxane matrix by two methods, physical blending (PB) and chemical modification (CM). Mechanical, thermal and morphological properties of composites were studied by changing the percentage of POSS and investigated by thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and wide angle X-ray diffraction (XRD) measurements. The results show that the hybrid composites have better mechanical and thermal property than the parent polymer matrix, and CM-prepared composites show better reinforcing role compared with PB-prepared samples. The CM method was hydrosilylation reaction of octavinyl-POSS with hydrogen terminated poly(methylphenylsiloxane) (HPMPS) and the FTIR and NMR results of modified POSS revealed that hydrosilylation reaction took place successfully but was not complete. The modified POSS consisting partial segments of HPMPS attached to the central POSS core showed better distribution in matrix than PB-prepared POSS hybrid composites.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ítalo R. Coura ◽  
Ottavio R. D. R. Carmignano ◽  
Ana Pacheli Heitmann ◽  
Fernando S. Lameiras ◽  
Rochel M. Lago ◽  
...  

AbstractThe iron mine tailings accumulation in dams is an environmental and economic problem. The composite based on high-density polyethylene/iron mine tailing production for the application of wood plastic and some items of domestic plastic industry can be a good alternative to reduce the rejects in the environment. This work presents the influence of the processing methodology in the mechanical, thermal and morphological properties of composites based on the high-density polyethylene/iron mine tailing. Four methodology processing by continuous and/or batch mixing were available. The iron mine tailing particles in the polymer matrix promoted an increase in mechanical strength and thermal stability. Besides, the particles acted as flame retardant. The iron mine tailing materials produced using batch mixing showed more significant modifications in the properties due to the better dispersion of the filler as shown by scanning electron microscopy.


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