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The key focus of this work was to examine the effect of hybrid fiber reinforcement on thethermal properties of particulate based natural fiber-reinforced hybrid composites. Banana and sisal fiberswere selected as natural fiber reinforcements for the polyester matrix based composites, which wereproduced by mechanical stir mix technique. Thermo-Gravimetric Analysis (TGA) and Fourier-TransformInfrared Spectroscopy (FTIS) were conducted in accordance with American Society for Testing andMaterials (ASTM) standards for the characterization of the hybrid composites. The FTIS result shows thedisappearance of 1735 cm-1 peak, a notable evidence of NaOH treatment. The thermal analysis showedthat the hybridization significantly affected the high temperature stability of the composite, with 70%Sisal/30%Banana found to have the lowest high temperature mass loss at a temperature of 300–520oC, thushighest high temperature stability. Derivative Thermogravimetry (DTG) results shows a minor mass lossrate at a temperature range of 50–150oC as well as a major mass loss rate due to pyrolysis of key fiberconstituents such as cellulose, hemicellulose and lignin between 260 and 350oC. Also it was observed thatas the percentage of banana in the hybrid fiber increases the speed of high temperature mass loss reduces.

This paper comparatively study on fluidity, flexural strength, compressive strength and other mechanical properties of sisal fiber cement mortar and the base mortar. The results show that fluidity of sisal fiber makes sisal fiber cement mortar than that of the base group decreased about by 11.1%;When sisal fiber content is 4.5 kg/m3, water reducing agent is 2.78 kg/m3, the best mixing proportion of sisal fiber cement mortar for water: glue: sand = 0.45:1.:2.5, flexural strength improved by 52.4%, 54.3%, 20.1% respectively, compressive strength increased by-1.5%, 6.5% and-2.1%.And analyzed the mechanism of flexural and compressive from the chemistry of sisal fiber and cement.

The polypropylene/sisal fiber composites were prepared by twin screw extruder and vane extruder, respectively. The tensile test specimens perpendicular to the extrusion direction and parallel to the extrusion direction were prepared from the extruded composites, respectively. SEM observation showed that fiber orientation of sisal fiber in the composites was not obvious when the content of sisal fiber not more than 15wt%. When the content of sisal fiber was 15wt%, the ability to orientate of sisal fiber in the composite prepared by vane extruder was better than that of in the composite prepared by twin screw extruder, which the fiber orientation of sisal fiber was obvious along the extrusion direction in the composite. Tensile tests showed that the tensile properties of the composite parallel to the extrusion direction with 15wt% sisal fiber prepared by vane extruder were the best compared with other composites in this work. The results illustrated that the orientation of sisal fiber in the composites was beneficial to the improvement of the tensile properties of the composites.

In this paper, sisal fibers (SF) reinforced cellulose acetate composites were prepared using twin-screw extrusion followed by hot-press moulding technology. Both the mechanical properties and the biodegradable rate of the composite were investigated in terms of effect of initial length and mass content percentage of sisal fiber on. The results showed that the fibers tended to be shorter and thinner during the processing of twin-screw blending and the tensile and flexure strength of composites were enhanced, with the content or initial length of sisal fibers increasing. Furthermore, the biodegradation rate of the composite was forward at first, and gradually became slow in later period and then leveled off finally. In addition, Micro-morphologies of the fracture surface of the composite were visualized by scanning electron microscopy (SEM) to analyze the effect of initial length and content of sisal fibers on interfacial adhesion and the distribution of sisal fibers in the composites.

Surface characteristics including surface morphology and chemical composition of single sisal fiber and their influences on the interfacial adhesion of sisal fiber/phenolic resin composites were investigated by SEM, AFM, and XPS. The results showed that the surface of the untreated single sisal fiber contained a large amount of lignin (up to 51%). Chlorine dioxide treatment could reduce the surface lignin to a low content (20%). Removal of lignin from fiber surface could enhance the interfacial strength of sisal fiber/phenolic resin composites, giving rise to an increase by 36% in tensile strength. These results indicate that the surface properties of single sisal fiber can be tailored to improve the fiber/resin interfacial adhesion.

Composites based on polypropylene (PP) and sisal fiber (SF) were prepared by melt blending. Sisal fiber content was 30 phr. Organoclay (OMMT; Cloisite®30B) (1-7 phr) was incorporated into the composites. In addition, maleic anhydride grafted polypropylene (MAPP) was used as a compatibilizer to enhance the interfacial adhesion between PP matrix and sisal fiber and also to improve the dispersion of the organoclay in PP matrix. The addition of OMMT had insignificantly affected mechanical properties of SF/PP composites. However, flame retardancy and thermal stability of SF/PP composites were improved dramatically with the presence of OMMT.

Alkaline cooking is common method for fiber degumming. Microwave was used to improve the degumming process of sisal fiber in this study, and the influence of degumming time, degumming temperature, and the solution composition on degumming result under microwave heating was probed. The experiment results show that microwave heating has significant effect for sisal fiber degumming. The optimal parameters for sisal fiber degumming, such as microwave heating at 100 °C for 30min in 3% NaOH solution, were also obtained.

In this study, sisal fiber and lotus petiole fiber were compared in structure and properties. SEM photos showed that the sisal fiber surface was rough, but lotus petiole fiber was smooth. The thermal properties of lotus petiole fiber and sisal fiber were studied with TG, the results shown that the law of degradation of the two fibers is similar. FT-IR measurement could confirm that the composition of the two fibers was almost the same.

In order to enhance the interfacial interactions between the sisal fiber (SF) and the polypropylene (PP) matrix, a water-solubility hyperdispersant which has amphipathic structure and flexible segment was used. Experimental results revealed that when the content of hyperdispersant is 5 percent, the impact strength of the composites was 27.4 kJ·m-2 and the flexural strength of SF/PP composites was 40.1 MPa, which was 64 and 34 wt% higher than that of unmodified systems, respectively. Meanwhile, the crystallinity of the composites also leads to an increase.

By means of the tests on the mechanics performance of the reinforcing concrete mixed with sisal fibers or rubber powder of certain content are investigated. The compressive strength, tensile strength and flexural strength, etc. are compared. The test indicates that when the test condition is same, the compressive strength, tensile strength and flexural strength of the sisal fibers concrete are better than those of the rubber powder’s. The sisal fiber concrete is environment friendly than the rubber powder concrete. And it has widely value of spread and utilization.

According to experiments by comparing with normal cement concrete and other fiber reinforced concrete, they analyze the mechanical properties and features of sisal fiber reinforced concrete. Besides, they observe the fracture process of different ages and contents of sisal fiber reinforced concrete and analyze the bonding property, toughening effect and failure mechanism. The results show that sisal fiber reinforced concrete is superior to normal cement concrete on mechanical properties, and has a feature of multi-cracking, while compared with other fiber reinforced concrete, it is more economical.

Asbestos-free frictional material is developed by using phenol formaldehyde resins modified with nano- SiO2 as matrix while surface-treated sisal fiber and glass fiber are used as reinforcement. The friction and wear properties were investigated on Constant speed (D-SM) tester. The abrasion surfaces of composites were observed by scanning electron microscope (SEM). Test result shows that all the properties, such as, friction coefficient and wear can meet the GB5763-2008 requirement. When the sisal fiber and glass fiber hybrid ratio is 2:1, the composite has the high mechanical property, suitable and stable coefficient of friction and relatively low wearability especially at high temperature.

Ammonium polyphosphate (APP) and zinc borate (Zb), as flame retardants were incorporated into sisal fiber/polypropylene (PP) composites. Ratios of APP to Zb were varied. Maleic anhydride grafted polypropylene (MAPP) was used to improve the interfacial adhesion between polypropylene and fillers. Flammability of the composites was examined using a horizontal burning test, a vertical burning test, and a limiting oxygen index test. Morphology and mechanical properties of the composites were also investigated. The composite containing 30 phr of APP and 10 phr of Zb exhibited better flame retardancy than the composites containing other ratios of APP to Zb. The combination of APP and Zb insignificantly changed mechanical properties of the composites. In addition, SEM micrographs of the composites revealed good distribution of flame retardants and sisal fiber in PP matrix.

Sisal fiber/natural rubber (NR) composites were prepared by the incorporation of sisal fiber into NR at various content (10, 20, 30 phr) using a two-roll mill. Natural rubber grafted with maleic anhydride (NR-g-MA) prepared in house was used to improve interfacial adhesion between sisal fiber and NR matrix. NR-g-MA contents were varied. Mechanical properties, morphologies, and cure characteristics of the composites were studied. Maximum torque, modulus at 100% strain (M100), modulus at 300% strain (M300), and hardness of the composites increased with increasing fiber content while scorch time, cure time, tensile strength, and elongation at break decreased. The addition of NR-g-MA into the composites gave a positive impact on M100, M300, tensile strength, and hardness. Moreover, increasing NR-g-MA content resulted in increased scorch time, cure time, maximum torque, M100, M300, tensile strength, and hardness of the composites. SEM micrographs of the composites revealed that the addition of NR-g-MA into the composites improved the interfacial interaction between sisal fiber and NR matrix. In addition, the compatibilized NR composites exhibited higher specific tensile strength and modulus than the carbon black/NR composites.

In this study, the effects of weave type and fiber content on the physical properties of woven sisal fiber/epoxy composites were investigated. Sisal fibers used in this work were obtained from Nakhon Ratchasima, Thailand. Both untreated and alkali-treated fibers were employed. The woven sisal fibers were manufactured by hand weaving process. The fiber content in sisal fiber/epoxy composites were 3 wt.%, 5 wt.% and 10 wt.%. The composites were cured at room temperatures. In order to determine mechanical properties of the composites, flexural and impact tests were applied. Flexural strength and flexural modulus of all composites were higher than those of pure epoxy resin and tended to increase with increasing fiber content. The impact strength of all composites was lower than that of pure epoxy resin. The composites containing 10 wt.% sisal fibers showed the highest impact strength. There was no definite influence of weave type on flexural properties of the composites. At 3 and 5 wt.% fiber, the composites containing plain weave fibers seemed to show a higher impact strength than the composites containing other weave types.