Mechanical, Morphological, Thermal and Dynamic Study of Composites of Unsaturated Polyesters-Date Palm Leaf Fiber DPLF

In order to improve the properties of unsaturated polyesters, this study discusses the possibilities of developing a natural waste, date palm leaf fiber DPLF, produced in the northern Algerian Sahara, associated with the polymer matrix of a thermosetting polyester resin UP. For this purpose, composite plates containing virgin fiber at rates of 6 and 10% were treated with an alkaline solution of 6% NaOH on the one hand, and a silane compound on the other. In this research, a mechanical study of strength and elongation at break was carried out. In addition, morphological behavior was followed by SEM scanning electron microscopy. ATG thermogravimetric analysis and energy flow were monitored by DSC differential scanning calorimetry. Also, a study of the water absorption capacity has been conducted. In addition, a dynamic mechanical analysis DMA was carried out. The findings of this study show that there is a favorable mechanical behavior for the composites containing the 6% and 10% DPLF fiber, with alkaline NaOH and Silane treatment. They also show that the chemical treatment with alkaline solution and silane gives composites certain thermal stability compared to those with untreated fiber. Findings also explore that the absorption of water by the various composites shows that the chemical treatment promotes some intermolecular associations with water. Findings also show that the storage modulus (E') increases when the composite contains 10% DPLF, treated and untreated, and the maximum value of the tangent moves towards the high temperature for the treated and untreated fiber composite.

Isolation and Characterization of Nanocrystalline Cellulose Isolated from Pineapple Crown Leaf Fiber Agricultural Wastes Using Acid Hydrolysis

Pineapple crown leaf fiber (PCLF) is one of the major biomass wastes from pineapple processing plants. It consists mostly of carbohydrate polymers, such as cellulose, hemicellulose, and lignin. It can be further processed to form a more valuable and widely used nanocrystalline cellulose (NCC). This study investigates the effect of hydrolysis time on the properties of the produced NCC. The acid hydrolysis was conducted using 1 M of sulfuric acid at hydrolysis times of 1–3 h. The resulting NCCs were then characterized by their morphology, functional groups, crystallinity, thermal stability, elemental composition, and production yield. The results show that the NCC products had a rod-like particle structure and possessed a strong cellulose crystalline structure typically found in agricultural fiber-based cellulose. The highest NCC yield was obtained at 79.37% for one hour of hydrolysis. This NCC also displayed a higher decomposition temperature of 176.98 °C. The overall findings suggest that PCLF-derived NCC has attractive properties for a variety of applications.

Study on Workability High Strength Concrete Containing Pineapple Leaf Fiber (PALF)

The addition of fibers in concrete increases bridging force in interfacial transition zones inside the concrete matrix. Pineapple Leaf Fiber (PALF) is a natural fiber that has the potential to replace artificial fibers as reinforcement on concrete. As reinforcement fiber in concrete, PALF will undergo fibrillation and water absorption in concrete mixture and will change the mechanical properties of fresh concrete. So, the purpose of this study is to study the workability characteristics of fresh state concrete given PALF. Some variations of PALF composition are 0.04, 0.09, and 0.15 % wt. of cement is mixed into fresh concrete mixture with water-cement (w/c) ratio variations of 0.35, 0.38, and 0.41. The planned concrete is high-strength concrete, then the provisions of determination of coarse and fine aggregates using sieve analysis according to high-strength concrete material standards and concrete mixtures are given superplasticizer 0.09% wt. of cement constantly for all mixtures. A slump test method is still an option in this study, where this method becomes the standard to determine workability effectively. The results showed that an increase in concrete strength was achieved in the addition of PALF composition in concrete compared to control (normal concrete), in addition to the tendency of the relationship between w/c ratio, slump value, and compressive strength in all PALF variations achieved in this study.