Interfacial Modification of Hemp Fiber Reinforced Composites Using Fungal and Alkali Treatment

2007 ◽  
Vol 1 (1) ◽  
pp. 109-117 ◽  
Author(s):  
K. L. Pickering ◽  
Y. Li ◽  
R. L. Farrell ◽  
M. Lay

Increasing worldwide environmental awareness is encouraging scientific research into developing cheaper, more sustainable materials. Industrial hemp fiber is one of the strongest and stiffest available natural fibers [K. L. Pickering, M. Priest, T. Watts, G. Beckermann, and S. N. Alam, J. Adv. Mater. 37, 15 (2005)] and therefore has great potential in composite materials. Incorporated into a thermoplastic matrix, it gives a structural material that is cheap, lightweight, and recyclable. However, natural fibers are commonly incompatible with common molding thermoplastics such as polypropylene, which limits the performance of the composites produced. The main objective of the current work was to investigate the use of fungi to treat hemp fiber to create better bonding characteristics in natural fiber reinforced polypropylene composites. X-ray diffraction (XRD), ζ-potential, lignin testing, thermal analysis, and scanning electron microscopy (SEM) were used to characterize the effect of treatment on hemp fibers. A combined alkali and fungi treated fiber composite produced the highest tensile strength of 48.3 MPa, an increase of 32% compared to composites with untreated fiber.

2011 ◽  
Vol 415-417 ◽  
pp. 666-670 ◽  
Author(s):  
Na Lu ◽  
Shubhashini Oza ◽  
Ian Ferguson

Natural fiber reinforced composites are being used as reinforcement material in composite system due to their positive environmental benefits. Added to that, natural fibers offer advantages such as low density, low cost, good toughness, high specific strength, relatively non-abrasive and wide availability. However, the low thermal stability of natural fibers is one of the major challenges to increase their use as reinforcing component. In this study, a thorough investigation has been done to compare the effect of two chemical treatment methods on the thermal stability of hemp fibers. 5wt% sodium hydroxide and 5wt% triethoxyvinylsilane was used for the treatment of hemp fibers. Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis were used for characterization of untreated and treated fiber. The results indicated that 24 hours alkali treatment and 3 hours silane treatment time enhanced the thermal stability of the hemp fiber. However, alkali treatment shows better improvement compared to silane treatment.


2005 ◽  
Vol 297-300 ◽  
pp. 1529-1533
Author(s):  
Jae Kyoo Lim ◽  
Jun Hee Song ◽  
Jun Yong Choi ◽  
Hyo Jin Kim

In recent years, the use of natural fibers as reinforcements in polymer composites to replace synthetic fibers like glass is presently receiving increasing attention. Because of their increasing use combined with high demand, the cost of thermosetting resin has increased rapidly over the past decades. However the widely used synthetic fillers such as glass fiber are very expensive compared to natural fibers. Natural fiber-reinforced thermosetting composites are more economized to produce than the original thermosetting. Moreover the use of natural fiber in thermosetting composites is highly beneficial, because the use of natural fibers will be increased. In this study, a bamboo fiber-reinforced thermoplastic composite that made the RTM was evaluated to mechanical properties.


2014 ◽  
Vol 592-594 ◽  
pp. 1195-1199
Author(s):  
Ashwin Sailesh ◽  
C. Shanjeevi ◽  
J.Jeswin Arputhabalan

The developments in the field of composite materials are growing tremendously day by day. One such development is the use of natural fibers as reinforcement in the composite material. This is attributed to the fact that natural fibers are environmental friendly, economical, easily available and non-abrasive. Mixing of natural fiber with Glass Fibers is finding increased applications. In this present investigation Banana – Bamboo – Glass fiber reinforced natural fiber composites is fabricated by Hand – Layup technique with varying fiber orientation such as [0°G, 90°BM, 0°BN, 0°G], [0°G, 0°BM, +45°BN, 0°G] and [0°G, 0°BM, 90°BN, 0°G] and are tested for its tensile strength. The tensile strength of the fabricated composites is evaluated. The results indicated that the natural fiber composite with the fiber orientation of [0°G, 0°BM, 90°BN, 0°G] can withstand more load when compared to the samples with other fiber orientation. Nomenclature Used: BN – Banana fiber BM – Bamboo fiber G – Glass fiber


2017 ◽  
Vol 909 ◽  
pp. 94-99
Author(s):  
Muhammad Muslimin Husin ◽  
Mohammad Sukri Mustapa ◽  
Md. Saidin Wahab ◽  
Ahmad Mubarak Tajul Arifin ◽  
Reventheran A.L. Ganasan ◽  
...  

Nowadays natural fiber and polymer matrix are being extensively used as alternatives in producing furniture like ceiling, floor and etc. to fulfill society demand instead of environmental friendly and saving cost. The objective of this study is to investigate the effects of maleic anhydride grafted polypropylene (MAPP) as a coupling agent for reinforcement between kenaf fiber (KF) and polypropylene (PP). The ratio of MAPP between 3% and 5% was observed to determine which composition ratio is better. The tensile strength for both 30% KF and 40% KF was treated through the alkali treatment process with 5% sodium hydroxide (NaOH). Kenaf fiber reinforced polypropylene (PP/KF) composites were melt blended and then used hydraulic molding test press machine for characterization to observe their tensile strengths by measuring their threshold. Tensile test was carried out to determine the tensile stresses of the composite at the best composition ratio of kenaf fiber that are 30% KF and 40% KF instead of MAPP ratio. The result shows 40% KF (5% MAPP) lead to better tensile performance compared to 40% KF (3% MAPP), 30% KF (5% MAPP) and 30% KF (3% MAPP). Meanwhile, Scanning electron microscopy (SEM) is used to observe the morphological comparison between untreated KF and treated KF as well as PP/KF. The good interfacial bonding between KF and PP was 5% MAPP rather than 3% MAPP due to the optimum strength received. Overall 5% MAPP with 40% PP/KF had shown the best result compared to others with the estimated tensile strength value of 21.38 MPa.


2016 ◽  
Vol 36 (1) ◽  
pp. 87-95
Author(s):  
U Shehu ◽  
MT Isa ◽  
BO Aderemi ◽  
TK Bello

In order to improve properties of natural fibers as reinforcement, different treatment methods have being adopted by researchers. However, the use of sodium hydroxide (NaOH) for the treatment of baobab pod fiber as reinforcement in low density polyethylene is sparsely reported. Therefore, this study, investigated the effect of 2 wt%, 4 wt% 6 wt%, 8 wt% and 10 wt%  concentration of NaOH on baobab pod fibers as reinforcement for low density polyethylene (LDPE). Two roll mill machine and hydraulic press at a pressure of 10 kN and temperature of 120oC aided the production of the composite. FT-IR was used to analyze the functional groups of the treated and un-treated fibers. The result showed the disappearance of the peak 1550 cm-1 corresponding to lignin after modification. Further, the composites were characterized for the following tensile strength (TS), modulus of elasticity (MOE), elongation at break, impact strength and water absorption. Preliminary studies on the effect of loading of the unmodified baobab fiber in the LDPE matrix showed desirable properties at 10 wt%, where fiber content was in the range of 5 wt% to 30 wt% at interval of 5 wt%. The composite produced from the 8 wt% NaOH modified fiber had the highest tensile strength, MOE, elongation at break. At this modification level, the tensile strength, MOE and elongation at break were about 75.48%, 92.18% and 28% respectively higher than the composite produced from unmodified fiber. Composite produced with 10 wt% NaOH modified fiber exhibited least water absorption of 1.80%, which was 50% lower than unmodified. These showed that the modification of the fiber improved the composite properties. These properties compared favorably with some reported properties for natural fiber reinforced polymer composites. http://dx.doi.org/10.4314/njt.v36i1.12


2016 ◽  
Vol 24 (7) ◽  
pp. 555-566 ◽  
Author(s):  
N. Venkatachalam ◽  
P. Navaneethakrishnan ◽  
R. Rajsekar ◽  
S. Shankar

India as a tropical agricultural country has great potential to develop and use fiber derived from agricultural waste. Natural fibers are an important by-product of extraction process and they can be used as reinforcement in composite products. Composites are developed with unsaturated polyester resin as the matrix with natural fiber as the reinforcement. The results show decreased strength and modulus with increasing the fiber volume fraction. This indicates ineffective stress transfer between the fiber and matrix due to lower adhesion. It is necessary to bring a hydrophobic nature to the fibers by suitable chemical treatments in order to develop composites with improved mechanical properties. In these review papers, different types of natural fibers are subjected to a variety of physical and chemical treatments. The types of treatments studied in these papers include Physical treatments such as beating and heating, and chemical treatments like alkalization, silane, acetylation and benzoylation. The effects of these treatments on mechanical properties of the composites are analyzed. Fractures are analyzed by using the scanning electron microscopy (SEM). Analysis by FTIR and DMA showed that physico-chemical changes of surfaces of treated natural fibers. In general, treatments to the fibers can significantly improve adhesion and reduce water absorption, thereby improving mechanical properties of the composites. The purpose of this review paper is to summarize the research work done on various pretreatments in the preparation of natural fiber reinforced composites and to highlight the potential use of natural fiber reinforced polymer composites in industry and its potential to replace the synthetic fiber composite and conventional materials in the future.


Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1567 ◽  
Author(s):  
Haoqun Hong ◽  
Ruijing Xiao ◽  
Quannan Guo ◽  
Hao Liu ◽  
Haiyan Zhang

Natural fiber reinforced polymer-based composites have been growing into a type of green composites. The properties of natural fiber reinforced polymer-based composites are closely related to the structure of natural fibers. Bagasse fiber (BF) is one of the most used natural fibers for preparing natural fiber reinforced polymer-based composites. However, few examples of previous research touch on the quantitatively characterization of structure of BF and its effect on the properties of BF reinforced polymer-based composites. In this work, four kinds of BF including untreated BF (UBF), alkali treated BF (ABF), BF modified by silane coupling agent (SBF), and BF modified combining alkali treatment with silane coupling agent (ASBF) were prepared and melting blended with polylactic acid (PLA) to prepare PLA/BF composites. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TGA) and mechanical properties testing were used to characterize and analyze the structure and properties of modified BF and its reinforced PLA-based composites. Results showed that the used methods changed the structure of BF and their bonding modes. The surface energies of UBF, ABF, SBF, and ASBF were 19.8 mJ/m2, 34.7 mJ/m2, 12.3 mJ/m2, and 21.6 mJ/m2, respectively. The O/C ratios of UBF, ABF, SBF and, ASBF are 0.48, 0.53, 0.47, and 0.51. Due to the synergistic effect of alkali treatment and silane coupling agent modification on the surface chemical properties, the content of silicon elements on the surface of ASBF (4.15%) was higher than that of ASBF (2.38%). However, due to the destroying of alkali treatment on the microstructure of BF, the alkali treatment had no prominently synergetic effect with coupling agent modification on the mechanical properties of PLA/BF composites. Alkali treatment removed the small molecular compounds from BF, decreased its thermal stability, and increased the crystalline region and crystallinity of cellulose. Meanwhile, alkali treatment made BF fibrillated and increased its contactable active area with the coupling agents, but destructed the nature structure of BF. The silane coupling agent played a more important role than alkali treatment did in improving the interfacial compatibility of PLA/BF composites.


Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1316 ◽  
Author(s):  
Samsul Rizal ◽  
Ikramullah ◽  
Deepu Gopakumar ◽  
Sulaiman Thalib ◽  
Syifaul Huzni ◽  
...  

Natural fiber composites have been widely used for various applications such as automotive components, aircraft components and sports equipment. Among the natural fibers Typha spp have gained considerable attention to replace synthetic fibers due to their unique nature. The untreated and alkali-treated fibers treated in different durations were dried under the sun for 4 h prior to the fabrication of Typha fiber reinforced epoxy composites. The chemical structure and crystallinity index of composites were examined via FT-IR and XRD respectively. The tensile, flexural and impact tests were conducted to investigate the effect of the alkali treated Typha fibers on the epoxy composite. From the microscopy analysis, it was observed that the fracture mechanism of the composite was due to the fiber and matrix debonding, fiber pull out from the matrix, and fiber damage. The tensile, flexural and impact strength of the Typha fiber reinforced epoxy composite were increased after 5% alkaline immersion compared to untreated Typha fiber composite. From these results, it can be concluded that the alkali treatment on Typha fiber could improve the interfacial compatibility between epoxy resin and Typha fiber, which resulted in the better mechanical properties and made the composite more hydrophobic. So far there is no comprehensive report about Typha fiber reinforcing epoxy composite, investigating the effect of the alkali treatment duration on the interfacial compatibility, and their effect on chemical and mechanical of Typha fiber reinforced composite, which plays a vital role to provide the overall mechanical performance to the composite.


2019 ◽  
Vol 11 (11) ◽  
pp. 3163 ◽  
Author(s):  
Niyati Shah ◽  
Joseph Fehrenbach ◽  
Chad A. Ulven

In recent years there has been a substantial growth in the use of natural fiber reinforced composite in more advanced applications. However, high strength applications require high mechanical properties. Hybridization of natural fibers with synthetic fibers is an effective method of increasing the field of application and mechanical properties. The effects of hybridizing hemp (Cannabis sativa L.) fiber with recycled-carbon fiber were investigated in this study to determine the trends in mechanical properties resulting from varied weight fractions. Characterization of void content was accomplished using micro computed tomography (micro-CT). Through hybridizing hemp fiber and recycled carbon fiber in a polypropylene thermoplastic, a new class of high performance, low cost composites were demonstrated for injection molding applications. This study showcased a 10–15% increase in tensile strength after the reinforcement of recycled-carbon fiber with hemp fiber. A 30–35% increase was observed in the flexure strength after the reinforcement of recycled-carbon fiber with hemp fiber. Impact strength also had an increase of 35–40% for hemp fiber reinforced recycled-carbon fiber polypropylene composites.


2019 ◽  
Vol 12 (1) ◽  
pp. 4-76 ◽  
Author(s):  
Krittirash Yorseng ◽  
Mavinkere R. Sanjay ◽  
Jiratti Tengsuthiwat ◽  
Harikrishnan Pulikkalparambil ◽  
Jyotishkumar Parameswaranpillai ◽  
...  

Background: This era has seen outstanding achievements in materials science through the advances in natural fiber-based composites. The new environmentally friendly and sustainability concerns have imposed the chemists, biologists, researchers, engineers, and scientists to discover the engineering and structural applications of natural fiber reinforced composites. Objective: To present a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials. Methods: The patent data have been taken from the external links of US patents such as IFI CLAIMS Patent Services, USPTO, USPTO Assignment, Espacenet, Global Dossier, and Discuss. Results: The present world scenario demands the usage of natural fibers from agricultural and forest byproducts as a reinforcement material for fiber reinforced composites. Natural fibers can be easily extracted from plants and animals. Recently natural fiber in nanoscale is preferred over micro and macro scale fibers due to its superior thermo-mechanical properties. However, the choice of macro, micro, and nanofibers depends on their applications. Conclusion: This document presents a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials.


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