# Characterization of a New Fiber from Cyperus Dichrostachus A.Rich Plant

Authors: Belete Baye; Tamrat Tesfaye
Journal: Advances in Materials Science and Engineering
 (2022)

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## Abstract

Natural fibers have been good substitute sources for swapping synthetic fibers and reinforcing polymer matrices because of their contributions in maintaining ecology, low energy requirement for processing, and maintaining sustainability issues. The aim of this study was to characterize a new fiber from Cyperus Dichrostachus A.Rich (CDA) plant. The CDA plant is a perennial nonwoody grass found in Ethiopian high lands and river basins. The fiber from this plant has a chemical composition of cellulose (60.27%), hemicellulose (22.72%), and lignin (16.59%) contents. It has a density of 1010 kg/m3 and good tenacity of 105.76 cN/Tex with low elongation of 4.88%. The thermal stability of Cyperus Dicrostachus A.Rich fiber (CDAF) was studied using TGA and DTG analyses and revealed that the cellulose degraded at a temperature of 377.1°C. Fourier transform-infrared spectroscopy analysis confirmed that CDAF is rich in cellulose content. Additionally, CDAF can play a vital role as a new reinforcement material and best alternative in bio composite industries. This will give competitive advantages when evaluated with other natural fibers and reveal that there are significant potential benefits in implementation of “cleaner production” in textile material production industries. Specifically, the replacement of synthetic fiber source with renewable biomass will reduce the environmental impact of these fibers. The future study will be focused on investigating the possible valorization route, especially in paper board, composite reinforcement, and bio composite applications.


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## Body

## 1. Introduction

It has been obvious that numerous natural plants have been grown in different parts of the world, grown in agricultural domains, and after their lifetime, end up in landfills [1, 2], some other plants grow in the wild and spread around forest areas like CDA by their nature, some possess pharmaceutical properties, and others yield edible parts [3].Currently, perhaps, there have been many research works being put out which use natural fibers in different application areas. Most research works propose the use of plant fibers as reinforcement in polymer matrices, home furnishings, and construction industry. They have also been utilized even in apparel manufacturing applications. For this reason, it is necessary to study and characterize the natural fibers in order to add value on their current applications. Nowadays, new natural fibers [4–11] for multidisciplinary applications in reinforcements [12, 13], automotive engineering, and packaging applications are utilized.Starting from the 1980s, several natural fibers [14] including coir [15, 16], sisal [17–20], pineapple [21–24], jute [25–28], hemp [29, 30], palm [31–33], banana [34–37], and other fibers have been characterized and employed in many applications, for example, in reinforcement of polymer matrix in composites.Ethiopia can nurture a diversity of naturally fiber-forming plants. One of the most common plant that is currently grown commercially and could be of interest for handcrafting, packaging, and traditional equipment is Cyperus Dichrostachus A.Rich) plant (CDA) [38–41]. It is a tough plant, traditionally used for the weaving of shelters, mats, and baskets in Ethiopia and a number of countries in Africa [42, 43]. It has a decorative nature which is used to weave baskets, sleeping and sitting mats, rolled twines, more traditionally cereal and crop baskets, food baskets, crop and powder filters, covering devices for cooking devices, and other home apparatus.Yet, apart from traditional craftworks, there are no research works carried out on this plant regarding fiber extraction, its characterization, and modification of its properties. Therefore, the adaptation of this fiber into valuable goods was the motivation of this research work with technologies employed to transform it into beneficial products with characterized physical, mechanical, and chemical properties of the fiber. Most of these distinctive features were determined throughout the progress of the fiber extraction stages. The paper investigates the physical, morphological, chemical, thermal, and mechanical properties of CDA fiber with detailed scientific justifications.Because, though there are trends in using and utilizing of CDA plants for different applications in different literature studies, there are no literature studies regarding extraction and characterization of this plant for fibrous applications, especially for textile and composite manufacturing. Therefore, the aim of this research work was to extract and characterize CDA plant fibers for different applications as reinforcement in composite manufacturing, basketry, carpet making, and in textiles based on its inherent characteristics.


## 2. Materials and Methods

### 2.1. Materials

#### 2.1.1. CDA Plants

Well-matured CDA plants as shown in Figure1 were collected around the Blue Nile River, Bahir Dar, Ethiopia and fibers were extracted for characterization.Figure 1
Nonwoody CDA stems.


#### 2.1.2. Chemicals and Reagents

Different chemicals were used to achieve the objective of the research including sodium hydroxide and distilled water in their pure form. All chemicals used for this research are obtained from the Ethiopian Institute of Textile and Fashion Technology Laboratory, Bahir Dar, Ethiopia.


### 2.2. Methods

The CDA fibers were extracted at optimum extraction process by considering four influencing factors of 1.7% NaOH, 30°C temperature, 6:1MLR, and 90-minute extraction time with a maximal yield of 59.6% fiber having an optimized tensile strength of 247.68 cN/Tex.


#### 2.2.1. Characterization Methods

In order to determine the suitability of using extracted CDA fiber as a fiber source for the production of high-value materials, it was important to understand their physical and chemical properties. In this section, methods of such comprehensive characterization are reported.(1) Physical Properties. The physical properties of the fiber were characterized well after the extraction process was performed.Fiber Density:The density of the CDA fiber was measured using a liquid pycnometer, and the chemicals used were distilled water. Five replicates were performed for each sample type, and the density was calculated using (1) as per ASTM-D1577–01, 2005 standard.(1)ρgcm3=m2−m1m3−m1m4−m2ρt,whereρt = is the density of distilled water (g/cm3), m1= is the mass of empty pycnometer (g), m2= the mass of pycnometer with fibers (g), m3= the mass of pycnometer with distilled water (g), and m4= the mass of pycnometer with fibers and distilled water (g) [44].Optical Microscopic Analysis:The aspect ratio, shape of the fiber, and diameter of the fiber were measured using an optical microscope (40 x magnifications). For fiber diameter analysis, thirty-five distinct fiber samples were considered; and the microscopic images were taken along the longitudinal direction [45]. After calculating the average value of diameter, the diameter of extracted CDAF was compared with various plant fibers.Linear Density:The count of the extracted fiber was calculated in Tex units and measured by single-fiber weighing method through which the length of a single fiber was measured and the fiber weighed as per the ASTMD 2257 standard. Then linear density (Tex) was calculated using (2) to compare the fineness of the extracted fiber with other plant fibers.(2)FiberCountTex=wtg×1000Lengthm.Tensile Test:The tensile test was carried out using FAVIMAT + FIBRE TEST machine as per the ASTMD 3822-07 standard. The test was performed with the fiber samples of gauge length value 20 mm on the normal room temperature environment with 65% relative humidity at a cross head speed of 20 mm/min. Twenty samples were tested, and their average value was taken as the nominal tensile strength value of the fiber [45].Moisture Regain and Moisture Content:Moisture regain of CDA fiber was measured according to the ASTMD 1776/D1776M-16 as shown in (3) and (4). The samples were kept in a humidity chamber at 65% RH and room temperature for a set period of time and by oven drying the fibers at 105°C. The moisture regain was calculated as the ratio of the amount of water absorbed to the dry weight of the sample, and the moisture content was calculated as the ratio of the amount of moisture absorbed by the fiber to the original mass of the fiber before oven drying.(3)moistureregain%=WO×100,(4)Moisturecontent%=Woriginalwt×100,where Wis the weight of water in the fibers (g) and O is the oven-dried fiber weight (g).(2) Thermal Property Analysis. A thermogravimetric analyzer, TGA 4000 Perkin Elmer machine, was used to measure the degradation characteristics, the mass, and transformation of CDAFs in nitrogen atmosphere with a flow rate of 20 ml/min [44, 46, 47]. All the measurements were examined with an aluminum crucible [48] for good coupling between the sample and the heat measured by the thermocouple in a temperature range from 30° to 700°C at a heating rate of 20℃/min.(3) Chemical Composition. Chemical analysis was performed to determine the contents of cellulose, hemicellulose, lignin, wax, moisture, and ash of CDAFs by following conventional chemical analysis techniques as shown in Figure 2 [49, 50]. Chemical analysis of the extracted CDAF was performed by adapting TAPPI methods [51, 52].Lignin Content:The TAPPI T222 method [53] was used with prehydrolysis of the extracted sample with 72 wt. % sulfuric acid at room temperature for 2 hrs to determine the content of acid-insoluble lignin [51, 53–55]. Thereafter, the acidic dispersion of lignin was filtered through filter paper having an average pore size of 11 μm. The residue of lignin was washed on the filter with hot water up to neutral pH followed by drying at 105°C to constant weight. Accordingly, the extracted CDAF sample of 3 g was mixed with 150 mL of 72% sulfuric acid in a 500-ml flask and prehydrolyzed at room temperature for 2 hrs. [55]. The concentrated acid was diluted to 3% with distilled water, and the sample was hydrolyzed on a heating plate at boiling temperature for 4 hours using flask beakers. After cooling at room temperature for 30 min, the acidic dispersion of lignin settles overnight, and the liquid phase becomes transparent.The sediment of lignin was washed with hot water and with distilled water to a neutral media, separating the liquid phase from lignin by sedimentation followed by filtration with a filter paper. The washed lignin was dried using an aluminum sheet at 105°C to constant weight. The percentage of acid-insoluble lignin [56] in the extracted fiber sample is calculated by using (5) [54, 57]:(5)AIL=P−PtPs100%,where P is the weight of dry acid-insoluble lignin with aluminum sheet, Pt. is the weight of empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample.Cellulose and Hemicellulose Content:The determination of cellulose and hemicellulose was based on the separation of holocellulose which contains both cellulose and hemicellulose. First, the extracted CDAF sample, 2 g, was placed into a 200 ml flask, and then 160 mL distilled water, 2.0 g sodium chlorite (NaClO2), and 4 mL glacial acetic acid were added into the flask. The flask was covered with a Petri dish and put into a water bath with a temperature of 90°C and treated for 1 hr though magnetic stirring. Then to the flask an additional portion of 2.0 g sodium chlorite and 4 mL acetate buffer were added, and the treatment was continued again for an hour. After cooling at room temperature for 45 min, a dispersion of holocellulose was poured out into a 500 mL beaker and settled overnight. The sediment of holocellulose was washed with hot water and finally with distilled water up to a neutral pH, separating the liquid phase from holocellulose by sedimentation overnight. The washed holocellulose was dried in the aluminum sheet at 105°C to a constant weight. Then, the percentage of holocellulose in the extracted CDAF was calculated using (6) [57]:(6)HC=P−PtPs×100,where P is the weight of dry holocellulose together with the aluminum sheet, Pt. is the weight of the empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample [53, 54]. Then, the content of cellulose was obtained from holocellulose hydrolyzed with dilute hydrochloric acid to remove hemicelluloses based on the TAPPI T201 wd-76 and TAPPI T 9 wd-75 standards.Figure 2
Schematic representation of chemical analysis of CDA fiber.The dried holocellulose sample was mixed with 180 mL of 2% HCl in a 500-ml flask, and the sample was hydrolyzed with dilute acid at boiling temperature for 2 h followed by cooling at room temperature for 30 min. Then, the acidic dispersion of cellulose was segmented overnight for 1 hr. The sediment of cellulose was washed with hot water and finally with distilled water to a neutral pH, monitored by separating the liquid phase from cellulose by sedimentation and filtration with a filter paper. Then, the cellulose was dried in an aluminum sheet at 105°C to constant weight. The percentage of cellulose (C) and hemicellulose (H) in the extracted CDAF was calculated using (7) and (8), respectively:(7)C=HCp−PtPs,(8)H=HC–C,where HC is the percentage of holocellulose, P is the weight of dry cellulose together with flask, Pt. is the weight of empty flask, and Ps is the weight of extracted and dried biomass sample.(4) Fourier Transform Infra-red (FTIR) Spectroscopy. FTIR Spectrometer, Spectrum (Perkin Elmer) was employed to identify the functional groups present in the CDA fiber [46, 58]. The sample was compressed using a mechanical pressure pellet maker for 1 minute at 65 kg/cm2 pressure condition to form pellets of small sizes. The spectrum was recorded in the range of 4000 to 400 cm−1 with 32 scans per minute and with the resolution of 4 cm−1.


## 2.1. Materials

### 2.1.1. CDA Plants

Well-matured CDA plants as shown in Figure1 were collected around the Blue Nile River, Bahir Dar, Ethiopia and fibers were extracted for characterization.Figure 1
Nonwoody CDA stems.


### 2.1.2. Chemicals and Reagents

Different chemicals were used to achieve the objective of the research including sodium hydroxide and distilled water in their pure form. All chemicals used for this research are obtained from the Ethiopian Institute of Textile and Fashion Technology Laboratory, Bahir Dar, Ethiopia.


## 2.1.1. CDA Plants

Well-matured CDA plants as shown in Figure1 were collected around the Blue Nile River, Bahir Dar, Ethiopia and fibers were extracted for characterization.Figure 1
Nonwoody CDA stems.


## 2.1.2. Chemicals and Reagents

Different chemicals were used to achieve the objective of the research including sodium hydroxide and distilled water in their pure form. All chemicals used for this research are obtained from the Ethiopian Institute of Textile and Fashion Technology Laboratory, Bahir Dar, Ethiopia.


## 2.2. Methods

The CDA fibers were extracted at optimum extraction process by considering four influencing factors of 1.7% NaOH, 30°C temperature, 6:1MLR, and 90-minute extraction time with a maximal yield of 59.6% fiber having an optimized tensile strength of 247.68 cN/Tex.


### 2.2.1. Characterization Methods

In order to determine the suitability of using extracted CDA fiber as a fiber source for the production of high-value materials, it was important to understand their physical and chemical properties. In this section, methods of such comprehensive characterization are reported.(1) Physical Properties. The physical properties of the fiber were characterized well after the extraction process was performed.Fiber Density:The density of the CDA fiber was measured using a liquid pycnometer, and the chemicals used were distilled water. Five replicates were performed for each sample type, and the density was calculated using (1) as per ASTM-D1577–01, 2005 standard.(1)ρgcm3=m2−m1m3−m1m4−m2ρt,whereρt = is the density of distilled water (g/cm3), m1= is the mass of empty pycnometer (g), m2= the mass of pycnometer with fibers (g), m3= the mass of pycnometer with distilled water (g), and m4= the mass of pycnometer with fibers and distilled water (g) [44].Optical Microscopic Analysis:The aspect ratio, shape of the fiber, and diameter of the fiber were measured using an optical microscope (40 x magnifications). For fiber diameter analysis, thirty-five distinct fiber samples were considered; and the microscopic images were taken along the longitudinal direction [45]. After calculating the average value of diameter, the diameter of extracted CDAF was compared with various plant fibers.Linear Density:The count of the extracted fiber was calculated in Tex units and measured by single-fiber weighing method through which the length of a single fiber was measured and the fiber weighed as per the ASTMD 2257 standard. Then linear density (Tex) was calculated using (2) to compare the fineness of the extracted fiber with other plant fibers.(2)FiberCountTex=wtg×1000Lengthm.Tensile Test:The tensile test was carried out using FAVIMAT + FIBRE TEST machine as per the ASTMD 3822-07 standard. The test was performed with the fiber samples of gauge length value 20 mm on the normal room temperature environment with 65% relative humidity at a cross head speed of 20 mm/min. Twenty samples were tested, and their average value was taken as the nominal tensile strength value of the fiber [45].Moisture Regain and Moisture Content:Moisture regain of CDA fiber was measured according to the ASTMD 1776/D1776M-16 as shown in (3) and (4). The samples were kept in a humidity chamber at 65% RH and room temperature for a set period of time and by oven drying the fibers at 105°C. The moisture regain was calculated as the ratio of the amount of water absorbed to the dry weight of the sample, and the moisture content was calculated as the ratio of the amount of moisture absorbed by the fiber to the original mass of the fiber before oven drying.(3)moistureregain%=WO×100,(4)Moisturecontent%=Woriginalwt×100,where Wis the weight of water in the fibers (g) and O is the oven-dried fiber weight (g).(2) Thermal Property Analysis. A thermogravimetric analyzer, TGA 4000 Perkin Elmer machine, was used to measure the degradation characteristics, the mass, and transformation of CDAFs in nitrogen atmosphere with a flow rate of 20 ml/min [44, 46, 47]. All the measurements were examined with an aluminum crucible [48] for good coupling between the sample and the heat measured by the thermocouple in a temperature range from 30° to 700°C at a heating rate of 20℃/min.(3) Chemical Composition. Chemical analysis was performed to determine the contents of cellulose, hemicellulose, lignin, wax, moisture, and ash of CDAFs by following conventional chemical analysis techniques as shown in Figure 2 [49, 50]. Chemical analysis of the extracted CDAF was performed by adapting TAPPI methods [51, 52].Lignin Content:The TAPPI T222 method [53] was used with prehydrolysis of the extracted sample with 72 wt. % sulfuric acid at room temperature for 2 hrs to determine the content of acid-insoluble lignin [51, 53–55]. Thereafter, the acidic dispersion of lignin was filtered through filter paper having an average pore size of 11 μm. The residue of lignin was washed on the filter with hot water up to neutral pH followed by drying at 105°C to constant weight. Accordingly, the extracted CDAF sample of 3 g was mixed with 150 mL of 72% sulfuric acid in a 500-ml flask and prehydrolyzed at room temperature for 2 hrs. [55]. The concentrated acid was diluted to 3% with distilled water, and the sample was hydrolyzed on a heating plate at boiling temperature for 4 hours using flask beakers. After cooling at room temperature for 30 min, the acidic dispersion of lignin settles overnight, and the liquid phase becomes transparent.The sediment of lignin was washed with hot water and with distilled water to a neutral media, separating the liquid phase from lignin by sedimentation followed by filtration with a filter paper. The washed lignin was dried using an aluminum sheet at 105°C to constant weight. The percentage of acid-insoluble lignin [56] in the extracted fiber sample is calculated by using (5) [54, 57]:(5)AIL=P−PtPs100%,where P is the weight of dry acid-insoluble lignin with aluminum sheet, Pt. is the weight of empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample.Cellulose and Hemicellulose Content:The determination of cellulose and hemicellulose was based on the separation of holocellulose which contains both cellulose and hemicellulose. First, the extracted CDAF sample, 2 g, was placed into a 200 ml flask, and then 160 mL distilled water, 2.0 g sodium chlorite (NaClO2), and 4 mL glacial acetic acid were added into the flask. The flask was covered with a Petri dish and put into a water bath with a temperature of 90°C and treated for 1 hr though magnetic stirring. Then to the flask an additional portion of 2.0 g sodium chlorite and 4 mL acetate buffer were added, and the treatment was continued again for an hour. After cooling at room temperature for 45 min, a dispersion of holocellulose was poured out into a 500 mL beaker and settled overnight. The sediment of holocellulose was washed with hot water and finally with distilled water up to a neutral pH, separating the liquid phase from holocellulose by sedimentation overnight. The washed holocellulose was dried in the aluminum sheet at 105°C to a constant weight. Then, the percentage of holocellulose in the extracted CDAF was calculated using (6) [57]:(6)HC=P−PtPs×100,where P is the weight of dry holocellulose together with the aluminum sheet, Pt. is the weight of the empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample [53, 54]. Then, the content of cellulose was obtained from holocellulose hydrolyzed with dilute hydrochloric acid to remove hemicelluloses based on the TAPPI T201 wd-76 and TAPPI T 9 wd-75 standards.Figure 2
Schematic representation of chemical analysis of CDA fiber.The dried holocellulose sample was mixed with 180 mL of 2% HCl in a 500-ml flask, and the sample was hydrolyzed with dilute acid at boiling temperature for 2 h followed by cooling at room temperature for 30 min. Then, the acidic dispersion of cellulose was segmented overnight for 1 hr. The sediment of cellulose was washed with hot water and finally with distilled water to a neutral pH, monitored by separating the liquid phase from cellulose by sedimentation and filtration with a filter paper. Then, the cellulose was dried in an aluminum sheet at 105°C to constant weight. The percentage of cellulose (C) and hemicellulose (H) in the extracted CDAF was calculated using (7) and (8), respectively:(7)C=HCp−PtPs,(8)H=HC–C,where HC is the percentage of holocellulose, P is the weight of dry cellulose together with flask, Pt. is the weight of empty flask, and Ps is the weight of extracted and dried biomass sample.(4) Fourier Transform Infra-red (FTIR) Spectroscopy. FTIR Spectrometer, Spectrum (Perkin Elmer) was employed to identify the functional groups present in the CDA fiber [46, 58]. The sample was compressed using a mechanical pressure pellet maker for 1 minute at 65 kg/cm2 pressure condition to form pellets of small sizes. The spectrum was recorded in the range of 4000 to 400 cm−1 with 32 scans per minute and with the resolution of 4 cm−1.


## 2.2.1. Characterization Methods

In order to determine the suitability of using extracted CDA fiber as a fiber source for the production of high-value materials, it was important to understand their physical and chemical properties. In this section, methods of such comprehensive characterization are reported.(1) Physical Properties. The physical properties of the fiber were characterized well after the extraction process was performed.Fiber Density:The density of the CDA fiber was measured using a liquid pycnometer, and the chemicals used were distilled water. Five replicates were performed for each sample type, and the density was calculated using (1) as per ASTM-D1577–01, 2005 standard.(1)ρgcm3=m2−m1m3−m1m4−m2ρt,whereρt = is the density of distilled water (g/cm3), m1= is the mass of empty pycnometer (g), m2= the mass of pycnometer with fibers (g), m3= the mass of pycnometer with distilled water (g), and m4= the mass of pycnometer with fibers and distilled water (g) [44].Optical Microscopic Analysis:The aspect ratio, shape of the fiber, and diameter of the fiber were measured using an optical microscope (40 x magnifications). For fiber diameter analysis, thirty-five distinct fiber samples were considered; and the microscopic images were taken along the longitudinal direction [45]. After calculating the average value of diameter, the diameter of extracted CDAF was compared with various plant fibers.Linear Density:The count of the extracted fiber was calculated in Tex units and measured by single-fiber weighing method through which the length of a single fiber was measured and the fiber weighed as per the ASTMD 2257 standard. Then linear density (Tex) was calculated using (2) to compare the fineness of the extracted fiber with other plant fibers.(2)FiberCountTex=wtg×1000Lengthm.Tensile Test:The tensile test was carried out using FAVIMAT + FIBRE TEST machine as per the ASTMD 3822-07 standard. The test was performed with the fiber samples of gauge length value 20 mm on the normal room temperature environment with 65% relative humidity at a cross head speed of 20 mm/min. Twenty samples were tested, and their average value was taken as the nominal tensile strength value of the fiber [45].Moisture Regain and Moisture Content:Moisture regain of CDA fiber was measured according to the ASTMD 1776/D1776M-16 as shown in (3) and (4). The samples were kept in a humidity chamber at 65% RH and room temperature for a set period of time and by oven drying the fibers at 105°C. The moisture regain was calculated as the ratio of the amount of water absorbed to the dry weight of the sample, and the moisture content was calculated as the ratio of the amount of moisture absorbed by the fiber to the original mass of the fiber before oven drying.(3)moistureregain%=WO×100,(4)Moisturecontent%=Woriginalwt×100,where Wis the weight of water in the fibers (g) and O is the oven-dried fiber weight (g).(2) Thermal Property Analysis. A thermogravimetric analyzer, TGA 4000 Perkin Elmer machine, was used to measure the degradation characteristics, the mass, and transformation of CDAFs in nitrogen atmosphere with a flow rate of 20 ml/min [44, 46, 47]. All the measurements were examined with an aluminum crucible [48] for good coupling between the sample and the heat measured by the thermocouple in a temperature range from 30° to 700°C at a heating rate of 20℃/min.(3) Chemical Composition. Chemical analysis was performed to determine the contents of cellulose, hemicellulose, lignin, wax, moisture, and ash of CDAFs by following conventional chemical analysis techniques as shown in Figure 2 [49, 50]. Chemical analysis of the extracted CDAF was performed by adapting TAPPI methods [51, 52].Lignin Content:The TAPPI T222 method [53] was used with prehydrolysis of the extracted sample with 72 wt. % sulfuric acid at room temperature for 2 hrs to determine the content of acid-insoluble lignin [51, 53–55]. Thereafter, the acidic dispersion of lignin was filtered through filter paper having an average pore size of 11 μm. The residue of lignin was washed on the filter with hot water up to neutral pH followed by drying at 105°C to constant weight. Accordingly, the extracted CDAF sample of 3 g was mixed with 150 mL of 72% sulfuric acid in a 500-ml flask and prehydrolyzed at room temperature for 2 hrs. [55]. The concentrated acid was diluted to 3% with distilled water, and the sample was hydrolyzed on a heating plate at boiling temperature for 4 hours using flask beakers. After cooling at room temperature for 30 min, the acidic dispersion of lignin settles overnight, and the liquid phase becomes transparent.The sediment of lignin was washed with hot water and with distilled water to a neutral media, separating the liquid phase from lignin by sedimentation followed by filtration with a filter paper. The washed lignin was dried using an aluminum sheet at 105°C to constant weight. The percentage of acid-insoluble lignin [56] in the extracted fiber sample is calculated by using (5) [54, 57]:(5)AIL=P−PtPs100%,where P is the weight of dry acid-insoluble lignin with aluminum sheet, Pt. is the weight of empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample.Cellulose and Hemicellulose Content:The determination of cellulose and hemicellulose was based on the separation of holocellulose which contains both cellulose and hemicellulose. First, the extracted CDAF sample, 2 g, was placed into a 200 ml flask, and then 160 mL distilled water, 2.0 g sodium chlorite (NaClO2), and 4 mL glacial acetic acid were added into the flask. The flask was covered with a Petri dish and put into a water bath with a temperature of 90°C and treated for 1 hr though magnetic stirring. Then to the flask an additional portion of 2.0 g sodium chlorite and 4 mL acetate buffer were added, and the treatment was continued again for an hour. After cooling at room temperature for 45 min, a dispersion of holocellulose was poured out into a 500 mL beaker and settled overnight. The sediment of holocellulose was washed with hot water and finally with distilled water up to a neutral pH, separating the liquid phase from holocellulose by sedimentation overnight. The washed holocellulose was dried in the aluminum sheet at 105°C to a constant weight. Then, the percentage of holocellulose in the extracted CDAF was calculated using (6) [57]:(6)HC=P−PtPs×100,where P is the weight of dry holocellulose together with the aluminum sheet, Pt. is the weight of the empty aluminum sheet, and Ps is the weight of extracted and dried CDAF sample [53, 54]. Then, the content of cellulose was obtained from holocellulose hydrolyzed with dilute hydrochloric acid to remove hemicelluloses based on the TAPPI T201 wd-76 and TAPPI T 9 wd-75 standards.Figure 2
Schematic representation of chemical analysis of CDA fiber.The dried holocellulose sample was mixed with 180 mL of 2% HCl in a 500-ml flask, and the sample was hydrolyzed with dilute acid at boiling temperature for 2 h followed by cooling at room temperature for 30 min. Then, the acidic dispersion of cellulose was segmented overnight for 1 hr. The sediment of cellulose was washed with hot water and finally with distilled water to a neutral pH, monitored by separating the liquid phase from cellulose by sedimentation and filtration with a filter paper. Then, the cellulose was dried in an aluminum sheet at 105°C to constant weight. The percentage of cellulose (C) and hemicellulose (H) in the extracted CDAF was calculated using (7) and (8), respectively:(7)C=HCp−PtPs,(8)H=HC–C,where HC is the percentage of holocellulose, P is the weight of dry cellulose together with flask, Pt. is the weight of empty flask, and Ps is the weight of extracted and dried biomass sample.(4) Fourier Transform Infra-red (FTIR) Spectroscopy. FTIR Spectrometer, Spectrum (Perkin Elmer) was employed to identify the functional groups present in the CDA fiber [46, 58]. The sample was compressed using a mechanical pressure pellet maker for 1 minute at 65 kg/cm2 pressure condition to form pellets of small sizes. The spectrum was recorded in the range of 4000 to 400 cm−1 with 32 scans per minute and with the resolution of 4 cm−1.


## 3. Results and Discussion

### 3.1. Physical Properties

#### 3.1.1. Diameter

The diameter of the fiber was 9.85 ± 7.16µm (Table 1 and Figure 3). The fibers exhibited nonuniform diameter, which indicates the unevenness of fiber thickness that may affect the spin ability and flexibility of the fiber during its end use.Table 1
Physical properties of CDAF.
ParameterResults for the extracted fiberDiameter (μm)9.85 ± 7.16Strength(cN/Tex)247 ± 87.68Moisture regain (%)12.83 ± 1.99Linear density(g/km) (tex)0.51 ± 0.244Fiber density (g/cm3)1.22 ± 0.52Elongation (%) (single test)7.75 ± 1.84Figure 3
Fiber diameter under optical microscope (40x).


#### 3.1.2. Tensile Strength

The bundle test results showed that the tensile strength of CDA fiber was 140.55 CN, and elongation of 3.6% has greater resistance against tensile loading and exhibited higher tensile properties. The fiber has a high number of OH-groups in the fiber that give additional strength and elongation to the fiber. On the other hand, the tensile strength of a single CDA fiber was found to be 951.84 ± 87.68 MPa with 8.95 ± 2.64% of elongation for each individual test. As compared to the tensile strengths of other fibers like flax (88–1500 MPa), hemp (550–900 MPa), jute (400–800 MPa), kenaf (240–600 MPa), and nettle (650–1594 MPa), CDAF has better strength for varied applications.


#### 3.1.3. Fiber Density

The fiber density was 1010 kg/m3. The density measurement was given equal importance to the mechanical property of the fiber since it distinguishes the natural fibers from synthetic fibers. From this fact, we can understand that the fiber has a lightweight property appropriate for different home furnishing applications, composites, and roof layering. The density of the new fiber was comparable with other natural fibers obtained from bagasse (1200 kg/m3), coir (1250 kg/m3), jute (1300 kg/m3) [45], Cyperus pangorei (1102 kg/m3), and bamboo (600-1100 kg/m3) [59, 60]. When compared with other natural fibers, the density of the CDA fiber was less than that of banana fiber (1350 kg/m3), pineapple leaf fiber (1400 kg/m3), kenaf fiber (1310 kg/m3), cotton fiber (1600 kg/m3), sisal (1330 kg/m3), and flax (1400 kg/m3) and higher than that of coconut (800 kg/m3) and palm fibers (920 kg/m3) [45, 61, 62] as shown in Table 2.Table 2
Comparison table of physical and tensile properties of CDAF with other natural fibers [45, 46, 60, 63].
FiberTensile strengthYoung's modulus (GPa)Density (g/cm3)Moisture regain (%)Elongation at break %Flax88-150060-801.410-121.2-1.6Hemp550-900701.48121.6Jute400-80010-301.4612.5-13.751.8Ramie500441.5122Coir22061.259.515-25Sisal600-700381.33132-3Cotton400121.518-8.53-10Kenaf295—1.28.3-10.22.7-6.9Bagasse20-29019.7-271.245-551.1Pine apple170-1672821.5121-3Banana35533.81.3512.05-13.3653Coconut131-1754-130.88-12.515-40Borassus65.24.91847.2Piassava134-1421.07-4.596.4-21.9Bamboo50335.910.6-1.114.51.4Palm97-1962.5-5.40.929.072-4.5Nettle65038111.7Cyperus pangorei196 ± 5611.6 ± 261.1029.21.69CDAF951.84 ± 789106.351.01012.40 ± 1.754.88 ± 2.64Note. The figures after + sign are standard deviations.


#### 3.1.4. Longitudinal Analysis of the Fiber

The longitudinal view of the fiber under a microscope, with a built-in video analyzer LEIKA [58], showed that the fiber has some convolutions and twisted structures along its length with a smooth, uniform, and good appearance as illustrated in Figure 4. The convolutions outfit for comfortable and comparable characteristics of the fiber as in cotton.Figure 4
Longitudinal view of the fiber (40x).


#### 3.1.5. Moisture Regain

The moisture regain of CDAF was 12.40 ± 1.75%, and the moisture content was 11.01 ± 1.38%. CDA fiber has a good moisture property like other natural fibers. The comparison of the physical properties and tensile properties of CDAF with other few natural fibers is presented in Table2.


### 3.2. Thermogravimetric Analysis

Natural fibers are made up of cellulose, hemicellulose, and lignin, by which their amount contributes for the thermal stability of the fibers. The thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) of CDA fiber are shown in Figure5. The initial degradation of the fiber is noticed (at 82.2°C) between room temperature and 109°C; this was due to the dehydration of the fiber [64]. The succeeding foremost degradation evolved from the temperature region of 110-410.5°C in which a peak quite close to 167.6°C was related to thermal depolymerization of hemicelluloses and some fraction of cellulose and lignin components [65] with 22.9% of mass loss. Hemicellulose started its decomposition easily, with the weight loss mainly happening at 220-330°C [65]. A precise noticeable peak at 377.1°C revealed a major mass loss of about 66.3% due to the breakage of glycosidic bonds of cellulose and alpha and beta alkyl ether linkages of lignin which led to the degradation of cellulose. Similar results were also observed at 331.1°C for Prosopis juliflora, 321°C for bamboo, 308.2°C for hemp, 298.2°C for jute, and 309.2°C for kenaf fibers [63].Figure 5
Thermogravimetric of extracted CDA fibers and DTG vs TGA.Moreover, the differential thermogravimetric (DTG) curve contributes to a more complete determination of temperatures of the onset and termination of the peak temperature of the fiber [66]. From the analysis of the DTG curve of CDA fiber, it has been shown that after moisture removal from the sample, the principal degradation peak was in the temperature range of 268.2-410.5°C (the maximum at 377.1°C) which corresponds to the thermal destruction of cellulose components [67].The second peak was positioned within the range of 410.5-607.5°C with the maximum at 486.9°C that follows the maximum rate of lignin thermal destruction [68, 69]. Therefore, from the DTG curve it can be justified that the fiber has more amount of cellulose than hemicellulose and lignin components. The summary is shown in Table 3.Table 3
Summary of TGA result.
Temperature/peakStage of degradationDegraded/decomposed componentReferenceBetween room temperature and 109°CInitial degradation of the fiber (at 82.2°C)Dehydration of moisture present in the fiber (11.2%)[70]110°-410°cThermal depolymerizationHemicelluloses and some fraction of cellulose and lignin components[65]220-330°CDecompositionLoss (22.9%) of hemicellulose[65, 71]377.1°CBreakage of glycoside bonds of cellulose andαand β−aryl-alkyl-ether linkages of ligninDegradation (57.1%) of cellulose[70, 72]


### 3.3. Chemical Composition

The chemical composition of CDAF is presented in Table4. CDAF has an estimated cellulose content of 60.27 ± 9.3% which is higher than that of kenaf (53.14%), bamboo (26-43%), wheat straw (51%), coconut tree leaf sheath (27%), piassava (28.6%), kudzu (33%), and sea grass (57%). The CDAF has 22.72 ± 9.61% of hemicellulose, which is greater than flax (18.6-20.6%), ramie (13-16%), hemp (15-22.4), bamboo (30%), wheat straw (15-31%), coconut tree leaf sheath (14%), piassava (25.8%), sisal(12%), and Prosopis juliflora (16.14%) and less than Napier grass strands (31.27%) [45, 57, 61, 62].Table 4
Chemical composition of CDA before and after extraction.
Cellulose (%)Hemicellulose %Lignin %Extractive %Ash %Moisture content %CDA plant48.1227.3621.533.05---2.88CDA fiber60.27 ± 9.322.72 ± 9.6116.59 ± 0.321.55 ± 0.0031.3011.01 ± 1.38Figure6 shows that there is a significant difference in chemical composition of the CDA plant before extraction and the extracted fiber. This shows that part of the lignin and hemicellulose components was removed by the alkali treatment which contributed to the high amount of cellulose in the fiber.Figure 6
Chemical composition of CDA plant before and after extraction of the fiber.As shown in Table4, CDAF contains hemicellulose (22.72 ± 0.32%) and high lignin (16.59 ± 0.32%) contents. The hemicellulose content gives good biodegradability, moisture absorption, and thermal property to the fiber [62]. Higher ranges of lignin help to retain water within the fiber, which safeguards the fiber from biological attacks [61]. Furthermore, CDA fiber has few extractives of wax and pectic substances (1.55 ± 0.003%) which enhance easier composite production due to higher bond strength between the matrix and the fiber during fabrication of composite structures. When compared with other natural fibers just like flax (1.5-1.7%), sisal (2%), nettle (3.1-4.2%), okra (3.9%), and abaca fibers (3%), they have comparably higher percentages of wax content than CDAF which has 1.55% of wax. The lesser percentage of wax enables chemical treatment, and it can also give an improved cohesive bonding between the fiber and composite matrix [55].The ash content (1.3%) of CDAF was found to be lower than other natural fibers like Cyperus pangorei (3.56%) and Prosopis juliflora (5.2%). CDA fiber has similar properties in composition with Cyperus pangorei fibers (68.5% cellulose, 17.88% lignin, 0.17% wax, 9.19% moisture content, and 1102 kg/m3 density) as shown in Table 5 [64].Table 5
Comparison of chemical composition of CDAF [45, 60, 73, 74].
FiberCellulose (%)Hemicellulose (%)Lignin (%)Wax (%)Bamboo26-433021-31----Ramie76151-8.0----Flax7118.6-20.62.21.5Kenaf7220.39----Jute61-7114-2012-130.5Cotton82.75.7--------Hemp6815100.8Ramie68-7613-160.6-0.70.3Abaca56-6320-257-93Sisal65129.92Coir32-430.15-0.250-45----Wheat straw38-4515-3112-20----Rice husk35-4519-2520----Rice straw41-57338-198-38Henequen602880.5Agave68.424.854.850.26Banana60-656-85-10----Nettle53-864-10.33.5-9.43.1-4.2Prosopis juliflora61.6516.1417.110.61Cyperus pangorei68.5----17.880.17-1.7Napier grass47.1231.2720.63----CDAF60.27 ± 9.322.72 ± 9.6116.59 ± 0.31.55


### 3.4. FTIR Analysis

Fourier-transform infrared spectroscopy is utilized for characterizing lingo cellulosic fiber to identify chemical compounds in a wide range of capacities, by considering the infrared features and transmittance bands of their constituents [75]. The FT-IR spectrum of CDA fiber is presented in Figure 7 and the details are shown in Table 6.Figure 7
FTIR spectral analysis curve for extracted fibers.Table 6
Functional group analysis result with FTIR.
Peaks (cm−1)Functional groupCompositionReference3751Strong O-H stretchingCellulose and its structure[76]33442906Vibration of methyl and methylene groups and C-H stretching vibrationCellulose and hemicellulose molecules[76]2504CH2 symmetrical stretchingWax[77]1923Carbonyl groupHemicelluloses[77, 78]1739C=O group stretching vibration of the ester groupHemicellulose or carboxylic acid in lignin[78, 79]1440 1337 1318CH2 deformation, CH2 wagging, and CH3 bending,Lignin[80]1241Stretching of C-O due to the vibration of the acetyl groupLignin[80]1164C-O-C groups asymmetric bridge stretchingHemicellulose and cellulose molecules[80]1055C–O aromatic ring and skeletal vibration of C-O-CCellulose[80]895B-glycosidic linkages between the sugar unitsHemicellulose and cellulose molecules[81]690C–H bond of aromatic hydrogenLignin compound[81]523Out of plane bonding of OH[81]The spectral graphs create the functional group sketch of the fiber, a distinguishing molecular fingerprint that can screen out and scan samples for diverse components of the fiber, and detect functional groups, distinguish the covalent bond relationship figures.


## 3.1. Physical Properties

### 3.1.1. Diameter

The diameter of the fiber was 9.85 ± 7.16µm (Table 1 and Figure 3). The fibers exhibited nonuniform diameter, which indicates the unevenness of fiber thickness that may affect the spin ability and flexibility of the fiber during its end use.Table 1
Physical properties of CDAF.
ParameterResults for the extracted fiberDiameter (μm)9.85 ± 7.16Strength(cN/Tex)247 ± 87.68Moisture regain (%)12.83 ± 1.99Linear density(g/km) (tex)0.51 ± 0.244Fiber density (g/cm3)1.22 ± 0.52Elongation (%) (single test)7.75 ± 1.84Figure 3
Fiber diameter under optical microscope (40x).


### 3.1.2. Tensile Strength

The bundle test results showed that the tensile strength of CDA fiber was 140.55 CN, and elongation of 3.6% has greater resistance against tensile loading and exhibited higher tensile properties. The fiber has a high number of OH-groups in the fiber that give additional strength and elongation to the fiber. On the other hand, the tensile strength of a single CDA fiber was found to be 951.84 ± 87.68 MPa with 8.95 ± 2.64% of elongation for each individual test. As compared to the tensile strengths of other fibers like flax (88–1500 MPa), hemp (550–900 MPa), jute (400–800 MPa), kenaf (240–600 MPa), and nettle (650–1594 MPa), CDAF has better strength for varied applications.


### 3.1.3. Fiber Density

The fiber density was 1010 kg/m3. The density measurement was given equal importance to the mechanical property of the fiber since it distinguishes the natural fibers from synthetic fibers. From this fact, we can understand that the fiber has a lightweight property appropriate for different home furnishing applications, composites, and roof layering. The density of the new fiber was comparable with other natural fibers obtained from bagasse (1200 kg/m3), coir (1250 kg/m3), jute (1300 kg/m3) [45], Cyperus pangorei (1102 kg/m3), and bamboo (600-1100 kg/m3) [59, 60]. When compared with other natural fibers, the density of the CDA fiber was less than that of banana fiber (1350 kg/m3), pineapple leaf fiber (1400 kg/m3), kenaf fiber (1310 kg/m3), cotton fiber (1600 kg/m3), sisal (1330 kg/m3), and flax (1400 kg/m3) and higher than that of coconut (800 kg/m3) and palm fibers (920 kg/m3) [45, 61, 62] as shown in Table 2.Table 2
Comparison table of physical and tensile properties of CDAF with other natural fibers [45, 46, 60, 63].
FiberTensile strengthYoung's modulus (GPa)Density (g/cm3)Moisture regain (%)Elongation at break %Flax88-150060-801.410-121.2-1.6Hemp550-900701.48121.6Jute400-80010-301.4612.5-13.751.8Ramie500441.5122Coir22061.259.515-25Sisal600-700381.33132-3Cotton400121.518-8.53-10Kenaf295—1.28.3-10.22.7-6.9Bagasse20-29019.7-271.245-551.1Pine apple170-1672821.5121-3Banana35533.81.3512.05-13.3653Coconut131-1754-130.88-12.515-40Borassus65.24.91847.2Piassava134-1421.07-4.596.4-21.9Bamboo50335.910.6-1.114.51.4Palm97-1962.5-5.40.929.072-4.5Nettle65038111.7Cyperus pangorei196 ± 5611.6 ± 261.1029.21.69CDAF951.84 ± 789106.351.01012.40 ± 1.754.88 ± 2.64Note. The figures after + sign are standard deviations.


### 3.1.4. Longitudinal Analysis of the Fiber

The longitudinal view of the fiber under a microscope, with a built-in video analyzer LEIKA [58], showed that the fiber has some convolutions and twisted structures along its length with a smooth, uniform, and good appearance as illustrated in Figure 4. The convolutions outfit for comfortable and comparable characteristics of the fiber as in cotton.Figure 4
Longitudinal view of the fiber (40x).


### 3.1.5. Moisture Regain

The moisture regain of CDAF was 12.40 ± 1.75%, and the moisture content was 11.01 ± 1.38%. CDA fiber has a good moisture property like other natural fibers. The comparison of the physical properties and tensile properties of CDAF with other few natural fibers is presented in Table2.


## 3.1.1. Diameter

The diameter of the fiber was 9.85 ± 7.16µm (Table 1 and Figure 3). The fibers exhibited nonuniform diameter, which indicates the unevenness of fiber thickness that may affect the spin ability and flexibility of the fiber during its end use.Table 1
Physical properties of CDAF.
ParameterResults for the extracted fiberDiameter (μm)9.85 ± 7.16Strength(cN/Tex)247 ± 87.68Moisture regain (%)12.83 ± 1.99Linear density(g/km) (tex)0.51 ± 0.244Fiber density (g/cm3)1.22 ± 0.52Elongation (%) (single test)7.75 ± 1.84Figure 3
Fiber diameter under optical microscope (40x).


## 3.1.2. Tensile Strength

The bundle test results showed that the tensile strength of CDA fiber was 140.55 CN, and elongation of 3.6% has greater resistance against tensile loading and exhibited higher tensile properties. The fiber has a high number of OH-groups in the fiber that give additional strength and elongation to the fiber. On the other hand, the tensile strength of a single CDA fiber was found to be 951.84 ± 87.68 MPa with 8.95 ± 2.64% of elongation for each individual test. As compared to the tensile strengths of other fibers like flax (88–1500 MPa), hemp (550–900 MPa), jute (400–800 MPa), kenaf (240–600 MPa), and nettle (650–1594 MPa), CDAF has better strength for varied applications.


## 3.1.3. Fiber Density

The fiber density was 1010 kg/m3. The density measurement was given equal importance to the mechanical property of the fiber since it distinguishes the natural fibers from synthetic fibers. From this fact, we can understand that the fiber has a lightweight property appropriate for different home furnishing applications, composites, and roof layering. The density of the new fiber was comparable with other natural fibers obtained from bagasse (1200 kg/m3), coir (1250 kg/m3), jute (1300 kg/m3) [45], Cyperus pangorei (1102 kg/m3), and bamboo (600-1100 kg/m3) [59, 60]. When compared with other natural fibers, the density of the CDA fiber was less than that of banana fiber (1350 kg/m3), pineapple leaf fiber (1400 kg/m3), kenaf fiber (1310 kg/m3), cotton fiber (1600 kg/m3), sisal (1330 kg/m3), and flax (1400 kg/m3) and higher than that of coconut (800 kg/m3) and palm fibers (920 kg/m3) [45, 61, 62] as shown in Table 2.Table 2
Comparison table of physical and tensile properties of CDAF with other natural fibers [45, 46, 60, 63].
FiberTensile strengthYoung's modulus (GPa)Density (g/cm3)Moisture regain (%)Elongation at break %Flax88-150060-801.410-121.2-1.6Hemp550-900701.48121.6Jute400-80010-301.4612.5-13.751.8Ramie500441.5122Coir22061.259.515-25Sisal600-700381.33132-3Cotton400121.518-8.53-10Kenaf295—1.28.3-10.22.7-6.9Bagasse20-29019.7-271.245-551.1Pine apple170-1672821.5121-3Banana35533.81.3512.05-13.3653Coconut131-1754-130.88-12.515-40Borassus65.24.91847.2Piassava134-1421.07-4.596.4-21.9Bamboo50335.910.6-1.114.51.4Palm97-1962.5-5.40.929.072-4.5Nettle65038111.7Cyperus pangorei196 ± 5611.6 ± 261.1029.21.69CDAF951.84 ± 789106.351.01012.40 ± 1.754.88 ± 2.64Note. The figures after + sign are standard deviations.


## 3.1.4. Longitudinal Analysis of the Fiber

The longitudinal view of the fiber under a microscope, with a built-in video analyzer LEIKA [58], showed that the fiber has some convolutions and twisted structures along its length with a smooth, uniform, and good appearance as illustrated in Figure 4. The convolutions outfit for comfortable and comparable characteristics of the fiber as in cotton.Figure 4
Longitudinal view of the fiber (40x).


## 3.1.5. Moisture Regain

The moisture regain of CDAF was 12.40 ± 1.75%, and the moisture content was 11.01 ± 1.38%. CDA fiber has a good moisture property like other natural fibers. The comparison of the physical properties and tensile properties of CDAF with other few natural fibers is presented in Table2.


## 3.2. Thermogravimetric Analysis

Natural fibers are made up of cellulose, hemicellulose, and lignin, by which their amount contributes for the thermal stability of the fibers. The thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) of CDA fiber are shown in Figure5. The initial degradation of the fiber is noticed (at 82.2°C) between room temperature and 109°C; this was due to the dehydration of the fiber [64]. The succeeding foremost degradation evolved from the temperature region of 110-410.5°C in which a peak quite close to 167.6°C was related to thermal depolymerization of hemicelluloses and some fraction of cellulose and lignin components [65] with 22.9% of mass loss. Hemicellulose started its decomposition easily, with the weight loss mainly happening at 220-330°C [65]. A precise noticeable peak at 377.1°C revealed a major mass loss of about 66.3% due to the breakage of glycosidic bonds of cellulose and alpha and beta alkyl ether linkages of lignin which led to the degradation of cellulose. Similar results were also observed at 331.1°C for Prosopis juliflora, 321°C for bamboo, 308.2°C for hemp, 298.2°C for jute, and 309.2°C for kenaf fibers [63].Figure 5
Thermogravimetric of extracted CDA fibers and DTG vs TGA.Moreover, the differential thermogravimetric (DTG) curve contributes to a more complete determination of temperatures of the onset and termination of the peak temperature of the fiber [66]. From the analysis of the DTG curve of CDA fiber, it has been shown that after moisture removal from the sample, the principal degradation peak was in the temperature range of 268.2-410.5°C (the maximum at 377.1°C) which corresponds to the thermal destruction of cellulose components [67].The second peak was positioned within the range of 410.5-607.5°C with the maximum at 486.9°C that follows the maximum rate of lignin thermal destruction [68, 69]. Therefore, from the DTG curve it can be justified that the fiber has more amount of cellulose than hemicellulose and lignin components. The summary is shown in Table 3.Table 3
Summary of TGA result.
Temperature/peakStage of degradationDegraded/decomposed componentReferenceBetween room temperature and 109°CInitial degradation of the fiber (at 82.2°C)Dehydration of moisture present in the fiber (11.2%)[70]110°-410°cThermal depolymerizationHemicelluloses and some fraction of cellulose and lignin components[65]220-330°CDecompositionLoss (22.9%) of hemicellulose[65, 71]377.1°CBreakage of glycoside bonds of cellulose andαand β−aryl-alkyl-ether linkages of ligninDegradation (57.1%) of cellulose[70, 72]


## 3.3. Chemical Composition

The chemical composition of CDAF is presented in Table4. CDAF has an estimated cellulose content of 60.27 ± 9.3% which is higher than that of kenaf (53.14%), bamboo (26-43%), wheat straw (51%), coconut tree leaf sheath (27%), piassava (28.6%), kudzu (33%), and sea grass (57%). The CDAF has 22.72 ± 9.61% of hemicellulose, which is greater than flax (18.6-20.6%), ramie (13-16%), hemp (15-22.4), bamboo (30%), wheat straw (15-31%), coconut tree leaf sheath (14%), piassava (25.8%), sisal(12%), and Prosopis juliflora (16.14%) and less than Napier grass strands (31.27%) [45, 57, 61, 62].Table 4
Chemical composition of CDA before and after extraction.
Cellulose (%)Hemicellulose %Lignin %Extractive %Ash %Moisture content %CDA plant48.1227.3621.533.05---2.88CDA fiber60.27 ± 9.322.72 ± 9.6116.59 ± 0.321.55 ± 0.0031.3011.01 ± 1.38Figure6 shows that there is a significant difference in chemical composition of the CDA plant before extraction and the extracted fiber. This shows that part of the lignin and hemicellulose components was removed by the alkali treatment which contributed to the high amount of cellulose in the fiber.Figure 6
Chemical composition of CDA plant before and after extraction of the fiber.As shown in Table4, CDAF contains hemicellulose (22.72 ± 0.32%) and high lignin (16.59 ± 0.32%) contents. The hemicellulose content gives good biodegradability, moisture absorption, and thermal property to the fiber [62]. Higher ranges of lignin help to retain water within the fiber, which safeguards the fiber from biological attacks [61]. Furthermore, CDA fiber has few extractives of wax and pectic substances (1.55 ± 0.003%) which enhance easier composite production due to higher bond strength between the matrix and the fiber during fabrication of composite structures. When compared with other natural fibers just like flax (1.5-1.7%), sisal (2%), nettle (3.1-4.2%), okra (3.9%), and abaca fibers (3%), they have comparably higher percentages of wax content than CDAF which has 1.55% of wax. The lesser percentage of wax enables chemical treatment, and it can also give an improved cohesive bonding between the fiber and composite matrix [55].The ash content (1.3%) of CDAF was found to be lower than other natural fibers like Cyperus pangorei (3.56%) and Prosopis juliflora (5.2%). CDA fiber has similar properties in composition with Cyperus pangorei fibers (68.5% cellulose, 17.88% lignin, 0.17% wax, 9.19% moisture content, and 1102 kg/m3 density) as shown in Table 5 [64].Table 5
Comparison of chemical composition of CDAF [45, 60, 73, 74].
FiberCellulose (%)Hemicellulose (%)Lignin (%)Wax (%)Bamboo26-433021-31----Ramie76151-8.0----Flax7118.6-20.62.21.5Kenaf7220.39----Jute61-7114-2012-130.5Cotton82.75.7--------Hemp6815100.8Ramie68-7613-160.6-0.70.3Abaca56-6320-257-93Sisal65129.92Coir32-430.15-0.250-45----Wheat straw38-4515-3112-20----Rice husk35-4519-2520----Rice straw41-57338-198-38Henequen602880.5Agave68.424.854.850.26Banana60-656-85-10----Nettle53-864-10.33.5-9.43.1-4.2Prosopis juliflora61.6516.1417.110.61Cyperus pangorei68.5----17.880.17-1.7Napier grass47.1231.2720.63----CDAF60.27 ± 9.322.72 ± 9.6116.59 ± 0.31.55


## 3.4. FTIR Analysis

Fourier-transform infrared spectroscopy is utilized for characterizing lingo cellulosic fiber to identify chemical compounds in a wide range of capacities, by considering the infrared features and transmittance bands of their constituents [75]. The FT-IR spectrum of CDA fiber is presented in Figure 7 and the details are shown in Table 6.Figure 7
FTIR spectral analysis curve for extracted fibers.Table 6
Functional group analysis result with FTIR.
Peaks (cm−1)Functional groupCompositionReference3751Strong O-H stretchingCellulose and its structure[76]33442906Vibration of methyl and methylene groups and C-H stretching vibrationCellulose and hemicellulose molecules[76]2504CH2 symmetrical stretchingWax[77]1923Carbonyl groupHemicelluloses[77, 78]1739C=O group stretching vibration of the ester groupHemicellulose or carboxylic acid in lignin[78, 79]1440 1337 1318CH2 deformation, CH2 wagging, and CH3 bending,Lignin[80]1241Stretching of C-O due to the vibration of the acetyl groupLignin[80]1164C-O-C groups asymmetric bridge stretchingHemicellulose and cellulose molecules[80]1055C–O aromatic ring and skeletal vibration of C-O-CCellulose[80]895B-glycosidic linkages between the sugar unitsHemicellulose and cellulose molecules[81]690C–H bond of aromatic hydrogenLignin compound[81]523Out of plane bonding of OH[81]The spectral graphs create the functional group sketch of the fiber, a distinguishing molecular fingerprint that can screen out and scan samples for diverse components of the fiber, and detect functional groups, distinguish the covalent bond relationship figures.


## 4. Conclusions

Nowadays, the need for recyclable, renewable, and sustainable materials has brought about the amplified consumption of natural fibers for reinforcing polymers to outfit a wide variety of applications. This study was mainly focused on the extraction and characterization of the lignocellulosic fiber derived from Cyperus Dichrostachus A.Rich plant. On the progress of this study, the new natural lignocellulosic fiber was successfully demonstrated to be an alternative source for producing fiber for varied applications.In general, the physical properties, chemical composition, thermal degradation, and mechanical properties of CDAF were characterized, and based on the results, the following conclusions were drawn:The results showed higher percentage of cellulose content (60.27 ± 9.3%), lignin content (16.59 ± 0.32%), and insignificant amount of ash content (1.3%) and moisture content (11.02 ± 1.38%).(i)
The density of the CDAF (1.01 ± 0.53 g/cm3) is low compared to other natural fibers; this makes CDAF the best alternative material in manufacturing of light weight polymer composite products.(ii)
The CDAF indicates high cellulosic content when compared with other natural fibers, which is markedly evident for good tensile properties.(iii)
The high tensile strength of CDAF and the lower density (1010 ± 534.62 kg/m3) make the fiber a good alternative for synthetic fibers and effective reinforcement for fabricating polymer composites and important constituent in lightweight materials like, mats, pillows, cushions, doors, and furniture.(iv)
It can be concluded that the CDA fiber is versatile and has engineering potential that can be used as effective reinforcement for a wide variety of applications.Future works will involve studies on the possible beneficiation route of the CDA fiber in textile industry and composite manufacturing. The possibility for paper and pulp production would also be analyzed.



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*Source: 4868809-2022-09-09.xml*