Recently, the demand for reinforced plastics from natural, sustainable, biodegradable, and environmentally friendly fibers has been rising worldwide. However, the main shortcoming of natural fibers reinforced plastics is the poor compatibility between reinforcing fibers and the matrix. Hence, it is necessary to form a strong attachment of the fibers to the matrix to obtain the optimum performance. In this work, chemical treatments (acid pretreatment, alkali pretreatment, and scouring) were employed on jute fibers to modify them. The mechanical properties, surface morphology, and Fourier transform infrared spectra of treated and untreated jute fibers were analyzed to understand the influence of chemical modifications on the fiber. Then, jute fiber/epoxy composites with a unidirectional jute fiber organization were prepared. Basic properties of the composites such as the void fraction, tensile strength, initial modulus, and elongation at break were studied. The better interfacial adhesion of treated fibers was shown by scanning electron microscope (SEM) images of fractured coupons. Hence, the chemical treatment of jute fiber has a significant impact on the formation of voids in the composites as well as the mechanical properties of jute fiber composites.
7 December 2019 in International Journal of Polymer Science
Recently, natural fibers have become attractive materials to engineers, scientists, and researchers as an alternative reinforcement for biocomposites. In this study, polylactic acid/abutilon natural straw biocomposites with various abutilon straw weight fractions were prepared by melt blending. The differential scanning calorimetric (DSC) results showed a significant influence of the abutilon straw on the melting behavior of PLA, even at the low abutilon straw contents. The dynamic mechanical analysis demonstrated that the storage modulus, as well as tan delta of the biocomposites, increased when the abutilon straw content increases, which indicates better interaction between abutilon natural straw and PLA. The incorporation of abutilon straw into biocomposites provided favorable changes in rheology related to the matrix. SEM observation revealed good dispersion of the abutilon straw in PLA.
In recent decades, natural-fiber-reinforced poly (lactic acid) (PLA) composites have received a great deal of attention. In this study, biocomposites of poly (lactic acid) and abutilon fibers are prepared by using melt blending and an extruder. The effects of fiber additions on rheological, thermomechanical, thermal, and morphological properties are investigated using a rheometer, dynamic mechanical analysis (DMA), differential scanning calorimeter (DSC), TGA, and SEM, respectively. The DSC results indicate that the fibers acted as a nucleating agent, which led to enhancing the crystallization of PLA. The results also reveal that the thermal stability of PLA was improved by abutilon fibers. Moreover, higher values of storage modulus are observed, which are attributed to strong interfacial adhesion. In addition, thetan delta isreduced upon the addition of fiber content into the PLA matrix, which restricts the mobility of PLA polymer molecules in the presence of the fibers. The improvement of the properties and energy absorption capabilities of such biocomposites signifies the great potential of abutilon fibers as reinforcement in green composites.
This study was conducted by analyzing the effect of surface treatment on wool using varying percentages of protease (3%, 6%, and 9%) with incorporating silver nanoparticles and by varying pH (i.e., pH = 4 and pH = 7). The comparison of fiber surface morphology and the FTIR analysis was done to characterize the nanocoating. The results showed that the antistatic and antibacterial effect on the samples treated at 3% protease and 6% protease were better than the samples treated at 9% protease. Correspondingly, the samples treated at pH 4 had better antistatic and antibacterial properties than those treated at pH 7. Sulfur compounds play a key role in interaction and absorption of silver nanoparticles.
The aim of this paper is to study wool fiber resources from Kenya that have been obtained from different breeds in order to characterize the basic properties of their wool to help improve the economic value of Kenyan wool. The Kenyan sheep industry has received less attention in terms of research and development when compared with large livestock. Wool quality and yield are essential to obtaining good returns in the international market. This study was conducted to analyze the wool yields and qualitative index of Kenyan sheep. The wool samples were taken from 95 crossbreed Dorper sheep comprising 23 males and 72 females between the ages of one and five years. Wool samples from the shoulders, flanks, back belly and legs were taken for analysis. The mean fleece weight was 2.04 ± 0.06 kg, with coefficient of variation of 37% for all the selected sheep; the average for the males was 2.06 ± 0.06 kg and the average for females was 2.02 ± 0.08 kg. The variation in the fleece weight was in the range of 0.7–3.3 kg. The yield percentages and impurities were analyzed and reported. The wide variations in fleece weight, the increase in sheep population and the trend of raw wool export suggests that there is potential for improving economic traits. Kenya can obtain trade benefits related to the wool industry by becoming a member of International Wool Trade Organization and by following economically sustainable practical approaches. It is essential to have good international and regional cooperation with countries that can share knowledge and training as well as marketing and information.
Oil–water separation is among the critical issues worldwide due to recent massive oil spills. Moreover, domestic and industrial water pollution due to oil discharge affects marine and aquatic life. Cotton is the most predominant fiber globally because of its use as a principal and popular clothing material. Cotton is also the leading raw material for technical and functional textile applications. In this study, the fabric was cured with poly (methyl methacrylate) (PMMA) nanoparticles to develop hydrophobic and oleophilic cotton fabrics. The dehydrating agents, N,N′-dicyclohexylcarbodiimide (DCC) and dimethyl aminopyridine (DMAP), were used to catalyze the esterification. The results proved that the excellent hydrophobicity of modified cotton fabric provides a water contact angle higher than 140°. In addition, Fourier transforms infrared (FTIR) spectroscopy, as well as X-ray photoelectron spectroscopy (XPS) analysis, confirmed the fabric surface modification. Surface morphological analysis by scanning electron microscope (SEM) revealed the uniform rough surface structure of the modified fabric with nano-coating. The modified fabric resulted in the high separation efficiency of oil and water, suggesting this strategy to be suitable for advanced oil–water separation.