Modeling of water diffusion mechanism in polypropylene/date palm fiber composite materials

The aim of this work is to model the water absorption mechanism of the polypropylene/date palm fibers composite materials after their exposure at different immersion conditions. For short immersion period, a model combining the Fick’s law and the time temperature stress principle has been proposed to describe the water absorption mechanism. However, it has been noted that, after a saturation time, the water diffusion mechanism leads to a physical degradation and a mass loss into the composite material, especially under high temperatures and long times of water immersion. Microscopic observations have revealed a decrease of the interfacial adhesion between the fibers and the matrix and fiber degradations. A general new model describing the evolution of the water uptake mechanism and the degradation phenomenon has been also proposed in the present work. A good agreement between the theoretical and experimental data has been obtained.

Download Full-text

Water Absorption and Stress Relaxation Behavior of PP/Date Palm Fiber Composite Materials

Design and Modeling of Mechanical Systems - II - Lecture Notes in Mechanical Engineering ◽

10.1007/978-3-319-17527-0_44 ◽

2015 ◽

pp. 437-445

Author(s):

Sonia Boukettaya ◽

Fahad Almaskari ◽

Ahmed Abdala ◽

Ahmad Alawar ◽

Hachmi Ben Daly ◽

...

Keyword(s):

Composite Materials ◽

Stress Relaxation ◽

Water Absorption ◽

Date Palm ◽

Fiber Composite ◽

Relaxation Behavior ◽

Stress Relaxation Behavior ◽

Palm Fiber ◽

Fiber Composite Materials

Download Full-text

Comparative Study of Polypropylene Matrix Reinforced with Date Palm Fibers & Date Palm Twigs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.123-125.1115 ◽

2010 ◽

Vol 123-125 ◽

pp. 1115-1118

Author(s):

Ahmad Alawar ◽

Waseem Ahmed ◽

Khalifa Al-Kaabi

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

Date Palm ◽

Fiber Composite ◽

Alkali Treatment ◽

Palm Tree ◽

Date Palm Fibers ◽

The Matrix ◽

Polypropylene Matrix ◽

Pp Composites

A variety of natural fibers have been on research over the past years to develop alternative echo friendly materials that have comparable performance as their synthetic counter parts for use in composite materials. In this study, two different forms of date palm tree fibers were used as reinforcement materials to develop composite materials with polypropylene (PP) matrix. These two different date palm fibers are namely Date palm fiber (DPF) & Date Palm twigs (DPT). These fibers were surface modified using alkali treatment. Two different Percentages of PP (50%, 75%) were mixed with the each type of fibers to form composite pellets using double screw extruder. The mechanical properties of the different fibers reinforced composite, in treated and untreated condition were investigated. The effect of different weight fraction of Polypropylene matrix reinforced DPF or Twigs fiber composite was investigated. The results indicate that untreated DPF-PP composites possess better mechanical properties compared to all untreated & treated DPT-PP composites. Mechanical interlocking between untreated fibers and the matrix showed some increase in the mechanical properties of the untreated DPF-PP compared to the treated one. In both cases, composites having 75% PP has better mechanical properties than the 50%PP composites. This is due to the lack of compatibility between the fibers and the matrix.

Download Full-text

Effect of Water Ingress on the Mechanical and Chemical Properties of Polybutylene Terephthalate Reinforced with Glass Fibers

Materials ◽

10.3390/ma14051261 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1261

Author(s):

Catarina S. P. Borges ◽

Alireza Akhavan-Safar ◽

Eduardo A. S. Marques ◽

Ricardo J. C. Carbas ◽

Christoph Ueffing ◽

...

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Water Uptake ◽

Significant Influence ◽

Water Immersion ◽

Water Diffusion ◽

Polybutylene Terephthalate ◽

Chemical Changes ◽

Water Ingress ◽

Effect Of Water

Short fiber reinforced polymers are widely used in the construction of electronic housings, where they are often exposed to harsh environmental conditions. The main purpose of this work is the in-depth study and characterization of the water uptake behavior of PBT-GF30 (polybutylene terephthalate with 30% of short glass fiber)as well as its consequent effect on the mechanical properties of the material. Further analysis was conducted to determine at which temperature range PBT-GF30 starts experiencing chemical changes. The influence of testing procedures and conditions on the evaluation of these effects was analyzed, also drawing comparisons with previous studies. The water absorption behavior was studied through gravimetric tests at 35, 70, and 130 °C. Fiber-free PBT was also studied at 35 °C for comparison purposes. The effect of water and temperature on the mechanical properties was analyzed through bulk tensile tests. The material was tested for the three temperatures in the as-supplied state (without drying or aging). Afterwards, PBT-GF30 was tested at room temperature following water immersion at the three temperatures. Chemical changes in the material were also analyzed through Fourier-transform infrared spectroscopy (FTIR). It was concluded that the water diffusion behavior is Fickian and that PBT absorbs more water than PBT-GF30 but at a slightly higher rate. However, temperature was found to have a more significant influence on the rate of water diffusion of PBT-GF30 than fiber content did. Temperature has a significant influence on the mechanical properties of the material. Humidity contributes to a slight drop in stiffness and strength, not showing a clear dependence on water uptake. This decrease in mechanical properties occurs due to the relaxation of the polymeric chain promoted by water ingress. Between 80 and 85 °C, after water immersion, the FTIR profile of the material changes, which suggests chemical changes in the PBT. The water absorption was simulated through heat transfer analogy with good results. From the developed numerical simulation, the minimum plate size to maintain the water ingress unidirectional was 30 mm, which was validated experimentally.

Download Full-text

Experimental prediction of internal defects according to defect area on NDI via water absorption behavior

International Journal of Modern Physics B ◽

10.1142/s021797922140021x ◽

2021 ◽

pp. 2140021

Author(s):

Kyo-Moon Lee ◽

Soo-Jeong Park ◽

Tianyu Yu ◽

Seong-Jae Park ◽

Yun-Hae Kim

Keyword(s):

Composite Materials ◽

Water Absorption ◽

Water Immersion ◽

Void Volume ◽

Matrix Degradation ◽

Internal Defects ◽

Experimental Prediction ◽

Defect Area ◽

Proportional Relationship ◽

The Relationship

This study analyzed the relationship between the defect area identified through a C-scan and the void volume in CF-PEKK composite materials through the water absorption behavior to predict the void volume. The water absorption content varies with the defect area; however, the defect area identified through a C-scan and the water absorption content did not show a proportional relationship. This is because voids are distributed in the through-thickness. The results indicated that the absorption behavior could be used to predict the void volume. Irreversible absorption was found to be independent of the void volume. Further, no matrix degradation was seen with water immersion at [Formula: see text]C; however, some local swelling was seen.

Download Full-text

Thermomechanical characterization of composite materials: Mortar reinforced by date palm fibers mesh from Marrakech

2015 3rd International Renewable and Sustainable Energy Conference (IRSEC) ◽

10.1109/irsec.2015.7455035 ◽

2015 ◽

Cited By ~ 1

Author(s):

Mustapha Boumhaout ◽

Lahcen Boukhattem ◽

Fatima Ait Nouh ◽

Hassan Hamdi ◽

Brahim Benhamou

Keyword(s):

Composite Materials ◽

Date Palm ◽

Date Palm Fibers ◽

Thermomechanical Characterization

Download Full-text

Physical and mechanical properties of mortars containing date palm fibers

Materials Research Express ◽

10.1088/2053-1591/ac48b7 ◽

2022 ◽

Author(s):

Saleh Bamaga

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Water Absorption ◽

Absorption Rate ◽

Date Palm ◽

Physical And Mechanical Properties ◽

Water Absorption Rate ◽

Date Palm Fibers ◽

Rate Test ◽

Construction Works

Abstract This paper presents the results of a study conducted to investigate the effects of incorporating Sefri Date Palm Leave Fibers (SDPLF) into the mortar. A total of seven mixtures were prepared and tested. SDPLF were collected from local farms. The fibers were then cleaned, dried, and cut to different sizes of 10 mm, 20 mm, and 50 mm, maintaining the same individual fiber width of approximately 5±2 mm. The content of SDPLF in mortars was kept to 1% and 3% by mass. The physical and mechanical properties of SDPLF fibers and SDPLF mortars were investigated. The compressive strength at 7, 14, and 28 days was determined. The water absorption rate test was carried out on mortars containing 1% SDPLF fibers. The results showed that mortars with SDPLF have lower workability, lower density, and lower compressive strength as compared to control mortars. However, they are still acceptable for use in construction works. Mortars containing 10 mm and 20 mm SDPLF fibers by mass showed significant improvement in terms of water absorption rate as compared to the control mortar.

Download Full-text

Evaluation of Water Diffusion Mechanism on Mechanical Properties of Polypropylene Composites

International Journal of Polymer Science ◽

10.1155/2020/8865748 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Oluwayomi Peter Balogun ◽

Adeolu Adesoji Adediran ◽

Joseph Ajibade Omotoyinbo ◽

Kenneth Kanayo Alaneme ◽

Isiaka Oluwole Oladele

Keyword(s):

Mechanical Properties ◽

Diffusion Model ◽

Water Immersion ◽

Diffusion Mechanism ◽

Water Diffusion ◽

Fickian Diffusion ◽

Reinforced Composites ◽

Compression Moulding ◽

Polypropylene Composites ◽

Fiber Matrix

This study evaluates the water diffusion mechanism on mechanical properties of polypropylene reinforced composites. Compounding of the composites into sheets was carried out using the compression moulding techniques by incorporating varying weight percentage of fibers and polypropylene. Mechanical properties of the composites were assessed according to ASTM standards, while the composite fracture surface was examined using a scanning electron microscope. The water absorption behaviour and diffusion mechanisms on mechanical properties of fabricated composites were analysed using a water immersion test and the Fickian diffusion model. The results show that mechanical properties of all polypropylene reinforced composites under dry condition was higher than wet condition. The composites reinforced with 7 wt.% (KOH and NaOH) fibers follow a consistent trend and gave the highest tensile strength and tensile modulus in comparison with pure PP (polypropylene). Addition of fibers into the polypropylene matrix gradually decreases composites impact strength with exception to 3 wt.% and 5 wt.% composites. The hardness properties of reinforced composites were steadily increased as the fiber loading increases which signify strong fiber-matrix bonding. The percentage of water absorbed for all reinforced composites increased as the fiber weight increases and slowly flattened off after 10 days of saturation. The morphological study revealed fiber pullout and delamination of reinforced composites attributed to poor fiber-matrix adhesion amount to water intake. The diffusion transport mechanism of polypropylene composites was observed to obey the Fickian diffusion model.

Download Full-text

Cooling rate effects on the crystallization kinetics of polypropylene/date palm fiber composite materials

Science and Engineering of Composite Materials ◽

10.1515/secm-2014-0324 ◽

2016 ◽

Vol 23 (5) ◽

pp. 523-533 ◽

Cited By ~ 2

Author(s):

Sonia Boukettaya ◽

Waseem Al Seddique ◽

Ahmad Alawar ◽

Hachmi Ben Daly ◽

Adel Hammami

Keyword(s):

Composite Materials ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Date Palm ◽

Crystallization Process ◽

Fiber Composite ◽

Degree Of Crystallinity ◽

Isothermal Crystallization Kinetics ◽

Palm Fiber ◽

Kinetics Of

AbstractNon-isothermal crystallization kinetics of polypropylene/date palm fiber (PP/DPF) composite materials were investigated in this study, using the differential scanning calorimetry (DSC) method. Different fiber contents and cooling rates, varying from 2.5°C/min to 20°C/min, were considered. The obtained results indicated that the initial crystallization temperature increases with the increase of the DPF content. This was attributed to the nucleating ability of these fibers. Several theoretical models were used to predict the non-isothermal crystallization kinetics of the materials considered in this study. Basically, it was shown that both the Avrami analysis, modified by Jeziorny, and the method developed by Mo could adequately describe such kinetics. The activation energies required during the overall crystallization process and at different amounts of the relative degree of crystallinity were also evaluated using the Kissinger method and the isoconversional analysis of calorimetric data, respectively. It was shown that the presence of the DPFs in the PP matrix decreases these energies, confirming their nucleating ability during the non-isothermal crystallization process.

Download Full-text