Around the world, there is a growing shift toward sustainable resources as we search for alternatives to synthetic materials that harm our environment. Natural fibers like jute, sisal, and flax have gained widespread attention for their environmental benefits. However, another potential resource, okra fiber, remains almost untouched. This oversight is particularly relevant for Bangladesh, where okra farming is extensive, and a significant portion of each harvest primarily the stalks goes to waste. By tapping into this underutilized resource, Bangladesh could not only reduce agricultural waste but also create new economic opportunities for rural communities.

This study explores two important questions that could reshape how we view okra fiber in both industrial and environmental contexts:

Previous research has shed light on the remarkable qualities of natural fibers like jute and sisal, which have become key players in sustainable industries. Yet, despite its high cellulose content and impressive physical properties, okra fiber hasn’t received the same level of attention. Only a handful of studies have explored its potential, and few have examined it in depth within Bangladesh, where we are one of the world’s top producers of this vegetable plant.

This study stands apart by offering a comprehensive look at okra fiber’s properties, comparing them with those of well-established natural fibers and considering how these fibers could benefit Bangladesh’s push for sustainability. By examining new chemical treatments and fabrication methods, this research aims to make okra fiber a serious contender in the world of sustainable materials. Ultimately, our goal is to turn an overlooked agricultural byproduct into a valuable resource that supports both economic growth and environmental well-being in Bangladesh.

According to data from FAOSTAT, Bangladesh’s okra production surged to 85,233 metric tons in 2022, marking a significant increase of 21.8% compared to the preceding year. This represents the highest production level on record for the country, with the lowest recorded output standing at 54,183 metric tons in 2019. Bangladesh ranks 8th among the 46 countries monitored in terms of okra production [1] . Figure 1 displays the chart where you can check the top 10 okra producing countries and Bangladesh is in the 8^th position in global production according to FAOSTAT.

Though we are using okra as a vegetable, now the question is, what about the plants after harvesting okra? The answer is that it’s being burned for cooking as fuel only and, in some cases, fed to animals. An investigation of the use of inedible plant parts after harvest was carried out in Konneripatti (Mettur) village, Edappadi, Salem, Tamil Nadu, India. The findings showed that the respondents’ uses for these inedible parts were diverse. In particular, 37% of farmers used the inedible parts of food crops as fuel, while 58% of farmers used them as animal feed. Furthermore, 2% and 3% of respondents used these parts to make shelter and rope, respectively. Unfortunately, a large quantity of stems from okra plants are thrown away in the field each year without being properly used [2] .

In order to investigate the important fibre characteristics, such as chemical composition, weight loss, burning behavior, and moisture content, the okra fibers were removed from the stalk of the plant after it had been treated with alkali and acid. To evaluate the morphological changes in the fibers throughout processing, Scanning Electron Microscopy (SEM) research was also conducted. To determine the presence of chemical groups in the fibers both before and after treatments, a Fourier transform infrared spectroscopy (FTIR) test was also performed. The work has shed information on how to better utilize okra fibers in textile production [2] . The results of SEM investigation show that non-cellulosic chemicals have overlapped and cemented the technical fibers. The test findings exhibit a high degree of resemblance to the physical, mechanical, and microstructural (cross-sectional and longitudinal view) features of other bast fibres [3] . Figure 2 illustrates scanning electron microscopy (SEM) appearance cross section of okra fibres fiber morphology.

Okra fibre derives from the Malvaceae family and is composed of roughly 60–70% cellulose and has good thermal characteristics, strength, and modulus [4] . Near the stem, on the outside of the plant’s center, is where the fiber is located. Similar to the bark fibers of jute, kenaf, flax, and hemp, the bast fiber of okra is bright, strong, and lustrous. It may also be spun into yarn. Clusters are formed when the pectin in the plant cell wall combines with the okra fibers [5] .

Below is a comparative table including come common properties of okra fiber alongside other natural fibers such as cotton, jute, hemp, and flax [6] [7] .

Table 1 highlights essential characteristics such as density, tensile strength, elongation at break, moisture absorption, thermal stability, and cellulose content. This comparison provides valuable insights into the performance and suitability of each fiber for various applications, including textiles and eco-friendly materials, helping researchers and manufacturers make informed choices based on material strength, flexibility, and sustainability. The following discussion focuses on key properties and their implications for various applications found during the preparation of the table:

Okra fiber has been used in very few studies. In the past, okra fiber was employed as a reinforcing filler to create composites using urea formaldehyde resin, biodegradable maize starch, poly lactic acid, and polyvinyl alcohol [8] .

Researchers found that 100% okra fiber by itself cannot be spun into yarn because of its reduced elasticity after examining the spin ability of staple okra to create spun yarn. The greatest alternative technology is therefore combining with different fibers. Okra-cotton blended yarns were made and examined in a ring spinning technique by S. Vanishree [9] .

On the other hand, researchers came to the conclusion that when bast fibers are blended, a lack of blend homogeneity and cohesion among fibers prevents the proportion of bast fibers in blended yarns from increasing [10] [11] . In order to satisfy the real demand in the textile weaving sectors, okra blended woven fabric can be regarded as a sustainable woven fabric because its performance fell within reasonable bounds considering the weight, thickness, air permeability, tensile strength, tear strength, abrasion, pilling, and fuzzing of the fabric. Furthermore, optical microscopic images were used to study the morphological characteristics of the fiber alignment in the structure of the woven fabric [12] . Figure 3 shows optical microscopic images of 80% polyester 20% okra blend woven fabric.

The idea of blending states that a fabric created from blended yarns typically has better properties than a fabric created from a single fiber [13] . A combination of woven fabric made of polyester and okra had a range of acceptable qualities. Owing to its affordability and the accessibility of okra fiber, PO blended fabrics show great promise and may be able to fill the real need for blended fabrics in the textile weaving sectors [12] .

A different study concentrated on producing composites made of Okra fiber (OF) with different fiber contents and polypropylene (PP) as the matrix material. Tensile, impact, and bending qualities were among the mechanical characteristics of both untreated and mercerized fibers that were methodically examined. Compared to untreated fiber composites, mechanized fiber composites showed better mechanical properties, with maximum tensile and bending strengths. With 45% fiber content, mercerized fiber composites showed optimal hardness and impact strength. Mechanical characteristics improved with exposure to different radiation. Water absorption, degradation, and interfacial characteristics were also investigated; fiber resulted in increased interfacial bonding between the matrix and fiber [14] .

Potentially used as reinforcement in composite materials, okra fiber can provide special mechanical qualities when incorporated into a matrix. Okra fiber can be harvested and processed appropriately to make composites with improved tensile and flexural strengths, comparable to those made with sisal and jute fibers [15] . Figure 4 illustrates the hybrid fiber composite (Jute, Okra, and Sisal) specimens subjected to tensile testing. Research done by using okra fiber for creating okra fiber reinforced polyester composites revealed superior tensile strength and modulus compared to pure polyester specimens [16] .

In another study, researchers explored the potential of okra fiber by developing a unique woven fabric used in creating PLA bio-composites. This study found that a composite with 20% okra woven fabric exhibited the best mechanical and thermal properties, demonstrating strong fiber-matrix bonding, making okra fiber a promising green material for automotive and packaging applications [17] . Another study highlights a sustainable fabric made from 100% okra fiber, comparing it with jute fabric. Okra fabric had slightly lower tensile strength but better elongation, tear strength, stiffness, and abrasion resistance, with less shrinkage. Both fabrics, after enzyme treatment, showed improved dyeing and color fastness. This research emphasizes the potential of okra fiber as a sustainable alternative for commercial applications [18] .

Researchers have focused on the potential of okra fiber as a sustainable alternative to synthetic fibers. It also reviews okra fiber’s extraction process, properties, and comparison with jute fiber, emphasizing its viability for various textile applications and advocating for its cultivation to boost farmers’ income while reducing greenhouse gas emissions from burning plant waste [19] . Researchers have found okra fibre as a potential material for green bio-composites [8] . Okra fibers, derived from the stem waste of okra plants, are biodegradable and exhibit high cellulose content, making them strong and suitable for polymer matrix composites. These fibers offer a sustainable alternative to synthetic materials, with good mechanical properties and color fastness, and can be further enhanced through eco-friendly chemical modifications [20] . Study’s findings indicate that the most promising industries for the okra industry are primarily those that use biodegradable matrices in their short-lived goods [21] . Focusing on the scenario, it can be easily measured that how okra fibre can be used in different fields and how we are wasting a valuable natural fibre as it can be used as fuel after the extraction of the fibre from the stem of the plant and the green parts of the plant can be used as animal feed.

We gathered okra plants from a farm close to Narayanganj. As per our observation, typically, the plant’s stem reaches a height of between 90 and 200 cm. The harvested plants were gathered while still green, and then the extraction technique was used. Fibers were extracted using the retting process with stagnant water.

The retting procedure eliminated the hemicelluloses, sticky pectin, and waxy epidermal tissue that held the fiber bundles together. Bundled okra plants were submerged in soft water for 10 days in a concrete tank. The soft pulp was then removed from the stalks by tapping them with a wooden hammer and scraping them with a knife. The fibers were re-immersed for five more days, then washed, combed, and sun-dried for two days. Figure 5 shows the collected okra plants. Figure 6 shows debarking of fibre from stem. Figure 7 shows macro view of the bark.

Fiber yield was calculated as 4% of the green plant’s weight using Chakma’s formula. The fibers were processed by scouring, bleaching, and dyeing. Scouring used a mixture of water, sodium hydroxide, wetting agents, and detergents, maintained at pH 10.5. Bleaching involved hydrogen peroxide, soda ash, and sodium silicate, processed at 70˚C - 80˚C for 8 hours [2] . Then, Fibre was tested for several properties that proved that it is one of the best alternatives of Jute, Kenaf, and Sisal and so on. As the fibre is primarily stiff, to soften and eliminate lignin, the stiff fiber was treated with NaOH, Na₂CO₃, and H₂O₂.

In order to create yarn, treated fiber was chopped and mixed with polyester in various proportions; however, 75/25 PO yarn broke. Yarns made of polyester and flax were also ready for comparison. Using ASTM standards, characteristics of the yarn and fabric were described, including linear density, strength, mass variation, and thread density.

Under carefully monitored circumstances, the fabric’s cover factor, weight, thickness, abrasion, pilling, air permeability, tensile strength, and tear strength were evaluated. All experiments were conducted under controlled conditions, and the results were tabulated for analysis [12] .

It is possible to create cellulose-based films from okra fibers, offering a sustainable alternative to conventional plastics. The process begins with the extraction of cellulose from okra stems and leaves, which involves de-waxing and delignification using alkali treatments to remove non-cellulosic components. The extracted fibers are then bleached with agents like hydrogen peroxide to obtain pure cellulose, followed by thorough washing and neutralization. The purified cellulose is dissolved in a suitable solvent system, such as an ionic liquid or an alkali-stabilizer solution, or converted into cellulose acetate through acetylation with acetic acid and acetic anhydride. The resulting solution is cast onto a smooth surface to form a thin film, which is then dried to remove residual solvent or moisture. Post-processing steps may include cutting, shaping, and applying additional coatings to enhance specific properties. These okra fiber-based films can be used in various applications, including biodegradable packaging, agricultural films, medical materials, and consumer products. While the biodegradability and renewable nature of okra make it an attractive resource, challenges such as extraction efficiency, mechanical properties, and cost-effectiveness need to be addressed through further research and optimization. Advances in chemical processing and material science could help overcome these challenges, making okra fiber films a viable eco-friendly alternative to traditional plastics [22] ( Figure 8 ).

The transformation of okra fiber into PET (polyethylene terephthalate) bottles involves several key processes. Initially, okra fibers are extracted through a water retting process, followed by drying and mechanical processing to isolate and purify the cellulose content. This cellulose is then chemically treated and dissolved using a solvent such as acetic acid, converting it into a viscous solution. Through a series of chemical reactions, the cellulose solution is polymerized into bio-based plastic resin, forming the base material for PET production. This bio-resin undergoes further processing, including polymerization and extrusion, to create PET pellets. The PET pellets are then melted and molded into preforms, which are subsequently blow-molded into the final PET bottle shape using high-pressure air. This innovative process not only utilizes renewable okra fibers but also contributes to sustainable plastic production, reducing reliance on petroleum-based raw materials and decreasing environmental impact. Figure 9 . Illustrating the transformation of okra fibre into PET bottles that will degrade or decompose within 3 months.

Okra fiber extraction and processing have shown to have enormous promise in a number of home and industrial industries. Okra plants that underwent retting produced fibers with a 4% yield of fiber based on the weight of the green plant. The fiber’s qualities were enhanced by the scouring, bleaching, and dyeing processes, which allowed it to compete with more conventional fibers like sisal, kenaf, and jute. Okra fiber’s potential for textile applications was confirmed by the remarkable linear density, strength, mass variation, and thread density found in the fibers, yarn, and fabric characterization carried out in accordance with ASTM (American Society for Testing and Materials) standards, specifically D2256, D1907, D5034, D737, D570, D1424, D3884 Test result was notable.

Additional testing revealed that okra fibers might be used to make cellulose-based films. These films can be used in consumer goods, medical materials, agricultural films, biodegradable packaging, and other uses where traditional polymers are not as sustainable. De-waxing, delignification, bleaching, and solvent casting were all steps in the transformation process that produced films that took advantage of okra’s renewable and biodegradable qualities.

The possibility of turning okra fibers into PET (polyethylene terephthalate) bottles was also investigated by the study. Okra cellulose underwent a series of chemical processing and polymerization steps to become a bio-based plastic resin. PET pellets were created by further processing this resin, which was then molded into preforms and blow-molded into bottles. When compared to conventional petroleum-based plastics, these PET bottles made of okra show a notable decrease in environmental effect since they degrade in three months.

Okra fiber’s adaptability encompasses a wide range of commercial and residential applications. Its use in packaging materials, bio-plastics, and textiles demonstrates how revolutionary it can be in a number of industries. The ability to turn okra fibers into sustainable and biodegradable products not only solves environmental issues but also offers a greener substitute for traditional materials. Subsequent investigations centered on refining mechanical characteristics, increasing extraction efficiency, and boosting economic viability may further establish okra fiber’s standing as a marketable, sustainable resource.

In our opinion, Bangladesh has a great chance to capitalize on the economic potential of okra fiber because of its burgeoning okra farming industry. Okra fiber, which is extracted from the plant’s stems, is a resource that is underutilized but has the potential to be important in a variety of sectors. The following are Bangladesh’s main okra fiber potentials:

As a key component of the movement towards sustainable economic development, this study emphasizes the revolutionary potential of okra fiber in Bangladesh. This research highlights the versatility and usability of okra fiber across a range of sectors by closely analyzing its physico-mechanical properties, chemical treatments, and production procedures. Said to be agricultural waste, okra fiber was once neglected but is now valued for its qualities, which are on par with those of typical natural fibers like sisal and jute.

The study highlights how crucial it is to improve extraction and processing methods in order to maximize fiber production and quality. The commercial feasibility of okra fiber can be further enhanced by innovations in chemical treatments and production techniques, positioning it as a competitive substitute for synthetic materials. To fully realize the promise of okra fiber, future research should concentrate on solving issues with mechanical characteristics and cost-effectiveness.

In conclusion, Bangladesh stands to gain a great deal economically and environmentally from realizing the potential of okra fiber. This research opens the door for sustainable development, job creation, and environmental preservation by turning agricultural waste into useful industrial resources. Okra fiber is a viable route to both global sustainability and economic prosperity, and it is expected to become a fundamental component of Bangladesh’s green economy.