OPTIMIZATION OF RETTING AND EXTRACTION THROUGH CONSTITUTIVE MATERIAL MODELLING OF PLANT STEMS FOR VARIABILITY REDUCTION IN EXTRACTED NATURAL FIBERS

2021 ◽  
Author(s):  
ANSHUL SINGHAL ◽  
AMY LANGHORST ◽  
ANKUSH BANSAL ◽  
MIHAELA BANU ◽  
ALAN TAUB

Natural plant fibers compared to glass fibers can provide a cost effective, lightweight and carbon negative reinforcement for polymer composites. However, the current commercial fiber extraction process induces defects including middle lamellae weakening during retting and kink bands during mechanical working. This leads to high variability in mechanical properties, making these fibers less favorable for structural applications at industrial scale. The aim of current research is to reduce this variability by studying the underlying mechanisms of natural fiber extraction to minimize fiber damage occurring at various steps in the process. In this study, flax stems were retted using the conventional dew/field and lab scale controlled enzymatic retting. The hand decorticated fibers from both methods were compared and enzymatic retting showed promising results in producing fine and uniform fibers as compared to fibers extracted by dew retting. To establish the constitutive parameters of the fibers for Finite Element Modeling (FEM), single retted flax stems were compression tested using a Texture Analyzer. This data can serve as the basis for modeling the mechanical deformation of plant stems passing through breaking rollers which is the first step in extraction after retting. The goal is to optimize the roller design and process conditions required to extract fibers with minimal damage and variability.

2004 ◽  
Vol os-13 (4) ◽  
pp. 1558925004os-13 ◽  
Author(s):  
Dieter H. Mueller

Composite materials and layered structures based on natural plant fibers are increasingly regarded as an alternative to glass fiber reinforced parts. One of their major field of application can be found in structural components for the automotive industry. Product examples are door trim panels or instrument panels. For such applications an utmost impact strength is required in order to implement a maximum of passenger safety by a good crash behavior. The paper describes the effects of several material parameters such as fiber fineness or fleece composition as well as the impact of the process conditions on this important composite characteristic.


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.


2011 ◽  
Vol 332-334 ◽  
pp. 121-125
Author(s):  
Xing Mei Guo ◽  
Yi Ping Qiu

The use of natural plant fibers as reinforcing fillers in fiber-polymer composites has drawn much interest in recent years. Natural plant fibers as reinforcing fillers have several advantages over inorganic fillers such as glass fibers; they are abundant, readily available, renewable, inexpensive, biodegradable, of low density, and of high specific strength. Hemp fibers are one of the most attractive natural plant fibers for fiber-reinforced composites because of their exceptional specific stiffness. In this review, we summarize recent progress in developments of the hemp fiber reinforced composites such as hemp fiber reinforced unsaturated polyester (UPE), hemp fiber reinforced polypropylene (PP), hemp fiber reinforced epoxy composites, and so on, illustrate with examples how they work, and discuss their intrinsic fundamentals and optimization designs. We are expecting the review to pave the way for developing fiber-polymer composites with higher strength.


Author(s):  
Faris M. AL-Oqla

The available potential plant waste could be worthy material to strengthen polymers to make sustainable products and structural components. Therefore, modeling the natural fiber polymeric-based composites is currently required to reveal the mechanical performance of such polymeric green composites for various green products. This work numerically investigates the effect of various fiber types, fiber loading, and reinforcement conditions with different polymer matrices towards predicting the mechanical performance of such natural fiber composites. Cantilever beam and compression schemes were considered as two different mechanical loading conditions for structural applications of such composite materials. Finite element analysis was conducted to modeling the natural fiber composite materials. The interaction between the fibers and the matrices was considered as an interfacial friction force and was determined from experimental work by the pull out technique for each polymer and fiber type. Both polypropylene and polyethylene were considered as composite matrices. Olive and lemon leaf fibers were considered as reinforcements. Results have revealed that the deflection resistance of the natural fiber composites in cantilever beam was enhanced for several reinforcement conditions. The fiber reinforcement was capable of enhancing the mechanical performance of the polymers and was the best in case of 20 wt.% polypropylene/lemon composites due to better stress transfer within the composite. However, the 40 wt.% case was the worst in enhancing the mechanical performance in both cantilever beam and compression cases. The 30 wt.% of polyethylene/olive fiber was the best in reducing the deflection of the cantilever beam case. The prediction of mechanical performance of natural fiber composites via proper numerical analysis would enhance the process of selecting the appropriate polymer and fiber types. It can contribute finding the proper reinforcement conditions to enhance the mechanical performance of the natural fiber composites to expand their reliable implementations in more industrial applications.


2016 ◽  
Vol 11 (1) ◽  
pp. 15-22
Author(s):  
Saeed Alkjk ◽  
Rafee Jabra ◽  
Salem Alkhater

Abstract The paper presents some of the results from a large experimental program undertaken at the Department of Civil Engineering of Damascus University. The project aims to study the ability to reinforce and strengthen the concrete by bars from Epoxy polymer reinforced with glass fibers (GFRP) and compared with reinforce concrete by steel bars in terms of mechanical properties. Five diameters of GFRP bars, and steel bars (4mm, 6mm, 8mm, 10mm, 12mm) tested on tensile strength tests. The test shown that GFRP bars need tensile strength more than steel bars. The concrete beams measuring (15cm wide × 15cm deep × and 70cm long) reinforced by GFRP with 0.5 vol.% ratio, then the concrete beams reinforced by steel with 0.89 vol.% ratio. The concrete beams tested on deflection test. The test shown that beams which reinforced by GFRP has higher deflection resistance, than beams which reinforced by steel. Which give more advantage to reinforced concrete by GFRP.


1983 ◽  
Vol 30 ◽  
Author(s):  
Ryszard Parosa

ABSTRACTIn the method described here, oxygen and air plasmas were generated at pressure of 1 – 10 Torr in quartz tube placed inside various kinds of microwave cavieties. Cavieties were supplied by 10 to 500 W of microwave power / f=2.45 GHz /. Processed fiber was fastly moved across the plasma region by special driving system. Experimentally the optimal process conditions, i.e. treatment time and gas pressure, were found. Moreover, a special construction of a “long” plasma reactor for industrial application of the process was worked out.


2017 ◽  
Vol 867 ◽  
pp. 41-47 ◽  
Author(s):  
Chitra Umachitra ◽  
N.K. Palaniswamy ◽  
O.L. Shanmugasundaram ◽  
P.S. Sampath

Natural fibers have been used to reinforce materials in many composite structures. Many types of natural fibers have been investigated including flax, hemp, ramie, sisal, abaca, banana etc., due to the advantage that they are light weight, renewable resources and have marketing appeal. These agricultural wastes can also be used to prepare fiber reinforced polymer hybrid composites in various combinations for commercial use. Application of composite materials in structural applications has presented the need for the engineering analysis. The present work focuses on the fabrication of polymer matrix composites by using natural fibers like banana and cotton which are abundant in nature and analysing the effect of mechanical properties of the composites on different surface treatments on the fabric. The effect of various surface treatments (NaOH, SLS, KMnO4) on the mechanical properties namely tensile, flexural and impact was analyzed and are discussed in this project. Analysing the material characteristics of the compression moulded composites; their results were measured on sections of the material to make use of the natural fiber reinforced polymer composite material for automotive seat shell manufacturing.


Fibers ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 59 ◽  
Author(s):  
Yunlong Jia ◽  
Bodo Fiedler

Poor moisture resistance of natural fiber reinforced bio-composites is a major concern in structural applications. Many efforts have been devoted to alleviate degradation of bio-composites caused by moisture absorption. Among them, fiber pre-treatment has been proven to be effective. This paper proposes an alternative “green” fiber pretreatment with furfuryl alcohol. Pre-treatments with different parameters were performed and the influence on the mechanical properties of fiber bundles and composites was investigated. Moisture resistance of composites was evaluated by water absorption tests. Mechanical properties of composites with different water contents were analyzed in tensile tests. The results show that furfuryl alcohol pretreatment is a promising method to improve moisture resistance and mechanical properties (e.g., Young’s modulus increases up to 18%) of flax fiber composites.


Author(s):  
S. H. Sheikh Md. Fadzullah ◽  
Zaleha Mustafa

There is an increasing interest worldwide in the use of Pineapple Leaf Fibers (PALF) as reinforcements in polymer composites, since this type of natural fiber exhibit attractive features such as superior mechanical, physical and thermal properties, thus offer potential uses in a spectrum of applications. PALF contains high cellulose content (between 70-82%) and high crystallinity. However, being hydrophilic, it posed a compatibility issue particularly in a hydrophobic polymeric matrix system. Thus, their shortcoming need to be addressed to ensure good interfacial bonding at the fibers/matrix interphase before their full potential can be harnessed. This chapter summarized some of the important aspects relating to PALF and its reinforced composites, particularly the main characteristics of the fiber, extraction and pre-treatment process of the fibers. Following this, discussions on the available fabrication processes for both short and continuous long PALF reinforced composites are presented.


Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 782 ◽  
Author(s):  
Wei Wang ◽  
Xiaomin Guo ◽  
Defang Zhao ◽  
Liu Liu ◽  
Ruiyun Zhang ◽  
...  

Environmentally sound composites reinforced with natural fibers or particles interest many researchers and engineers due to their great potential to substitute the traditional composites reinforced with glass fibers. However, the sensitivity of natural fiber-reinforced composites to water has limited their applications. In this paper, wood powder-reinforced polypropylene composites (WPCs) with various wood content were prepared and subjected to water absorption tests to study the water absorption procedure and the effect of water absorbed in the specimens on the mechanical properties. Water soaking tests were carried out by immersion of composite specimens in a container of distilled water maintained at three different temperatures, 23, 60 and 80 °C. The results showed that the moisture absorption content was related to wood powder percentage and they had a positive relationship. The transfer process of water molecules in the sample was found to follow the Fickian model and the diffusion constant increased with elevated water temperature. In addition, tensile and bending tests of both dry and wet composite samples were conducted and the results indicated that water absorbed in composite specimens degraded their mechanical properties. The tensile strength and modulus of the composites reinforced with 15, 30, 45 wt % wood powder decreased by 5.79%, 17.2%, 32.06% and 25.31%, 33.6%, 47.3% respectively, compared with their corresponding dry specimens. The flexural strength and modulus of the composite samples exhibited a similar result. Furthermore, dynamic mechanical analysis (DMA) also confirmed that the detrimental effect of water molecules on the composite specimens.


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