Effect of Alkaline Treatment and Coupling Agent on Thermal and Mechanical Properties of Macadamia Nutshell Residues Based PP Composites

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.

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Characterization of polypropylene composites reinforced with flax fibers treated by mechanical and alkali methods

Science and Engineering of Composite Materials ◽

10.1515/secm.2011.011 ◽

2011 ◽

Vol 18 (1-2) ◽

pp. 79-85 ◽

Cited By ~ 5

Author(s):

Wei Hu ◽

Minh-Tan Ton-That ◽

Johanne Denault ◽

Christian Belanger

Keyword(s):

Mechanical Properties ◽

Natural Fiber ◽

Alkali Treatment ◽

Alkaline Treatment ◽

Thermal And Mechanical Properties ◽

Polypropylene Composites ◽

Flax Fibers ◽

Fiber Separation ◽

As Stress

AbstractFlax is a type of natural fiber widely used as reinforcing materials for polymer composites. The commercially available flax fibers in Canada consist of a significant amount of shive and other impurities, which could act as stress concentration regions to negatively affect the mechanical property of composites. In this study, the shive was manually removed from the commercial flax fibers by screening and combing to obtain different shive contents from 0 to 30 wt%. By contrast, the obtained flax fibers were further treated with alkaline solution. The fibers obtained from mechanical and alkali treatment were compared on their thermal and mechanical properties. As expected, it was found that the thermal stability and mechanical properties of the flax reinforced polypropylene composites increased significantly with the removal of the shive content. However, the alkali treatment on flax fiber did not further improve the composites properties. The possible reason was that the proper mechanical treatment (screening and combing) prior to alkaline treatment effectively loosened the fiber bundles for better single fiber separation in matrix and significantly removed the impurities, thus the effect of alkaline treatment did not become obvious.

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Effect of alkali treatment and coupling agent on thermal and mechanical properties of Opuntia ficus-indica cladodes fibers reinforced HDPE composites

Polymer Bulletin ◽

10.1007/s00289-021-03619-8 ◽

2021 ◽

Author(s):

Anass Ait Benhamou ◽

Abdelghani Boussetta ◽

Mehdi Nadifiyine ◽

Amine Moubarik

Keyword(s):

Mechanical Properties ◽

Coupling Agent ◽

Alkali Treatment ◽

Thermal And Mechanical Properties ◽

Opuntia Ficus Indica

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Lignin as coupling agent in EPDM rubber: thermal and mechanical properties

Polymer Bulletin ◽

10.1007/s00289-015-1411-7 ◽

2015 ◽

Vol 72 (9) ◽

pp. 2389-2398 ◽

Cited By ~ 5

Author(s):

Ge Xu ◽

Guangyu Yan ◽

Jing Zhang

Keyword(s):

Mechanical Properties ◽

Coupling Agent ◽

Thermal And Mechanical Properties ◽

Epdm Rubber

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Mechanical Characterization of Polypropylene Natural Fibre Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.2737 ◽

2011 ◽

Vol 383-390 ◽

pp. 2737-2740 ◽

Cited By ~ 1

Author(s):

Sd Jacob Muthu ◽

Ratnam Paskaramoorthy

Keyword(s):

Mechanical Properties ◽

Mechanical Characterization ◽

Fibre Surface ◽

Alkaline Treatment ◽

Natural Fibre ◽

Fibre Composites ◽

The Matrix ◽

Pp Composites ◽

Fibre Loading

Using polypropylene (PP) as matrix and kenaf mat as reinforcement, composite test samples were fabricated by compression molding. Thereafter, the effect of fibre loading and the alkaline fibre surface treatment on the mechanical properties were studied. The kenaf/PP composites were found to have better mechanical properties than the polymer matrix. As expected, the interfacial bonding between the matrix and the fibres improved considerably when the fibres were subjected to alkaline treatment.

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Effect of surface treatment on moisture absorption, thermal, and mechanical properties of sisal fiber

Journal of Industrial Textiles ◽

10.1177/1528083720924774 ◽

2020 ◽

pp. 152808372092477 ◽

Cited By ~ 1

Author(s):

Adane Dagnaw Gudayu ◽

Leif Steuernagel ◽

Dieter Meiners ◽

Rotich Gideon

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Tensile Strength ◽

Moisture Absorption ◽

Natural Fibers ◽

Alkaline Treatment ◽

Automotive Application ◽

Sisal Fiber ◽

Thermal And Mechanical Properties ◽

The Impact

Natural fibers are increasingly being used as composite reinforcement for both thermoplastic and thermoset resin, mainly for automotive application. Due to their hydrophilic nature, natural fibers have certain limitations during composite manufacture especially owing to their poor resin wettability, weak fiber–polymer interface, high moisture absorption, and being affected by high temperature in case of thermoplastic resin. This work investigates the impact of sisal fiber modification techniques on moisture absorption, thermal, and mechanical properties of the fiber. Four sisal fiber samples were prepared; untreated, alkaline treated, acetylated, and a combined alkaline-treated/acetylation samples. The samples were evaluated for their hygroscopic nature, thermal stability, and tensile properties. It is found that acetylation resulted in a reduction of moisture absorption of sisal fiber as the acetylated and alkaline-treated/acetylated samples recorded a decrease of 42% and 28%, respectively. Alkaline treatment increased the absorbency owing to the removal of hemicellulose and lignin. The thermogravimetric result revealed that alkaline treatment improved the thermal stability as the alkali-treated and alkali-treated/acetylated samples showed improvement in thermal properties. The acetylated sample resulted in a significant reduction in tensile strength. But, the results from tensile tests of the alkaline-treated samples showed an insignificant decrease in tensile strength and improvement in the modulus for all treated samples. Fourier-transform infrared and scanning electron microscopic analysis were included in the study to supplement the results with structural and microstructural changes. The effect of those treatments on the sisal–PET composite properties was studied and will be submitted in part 2 of the study.

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