Bio-Based Products from Ramie Processing: From Fiber to Application

As demand for sustainable materials grows, ramie is emerging as a key player in eco-friendly manufacturing. This natural fiber, derived from the Boehmeria nivea Ramie, a plant, is prized for its strength, durability, and minimal environmental impact. Traditionally used in textiles, ramie is now being utilized in a range of bio-based products, including composites and bioplastics, offering a greener alternative to synthetic materials.

In this article, we’ll explore ramie’s origins, the innovative processing methods that transform it into valuable products, and its numerous applications across various industries. From fashion and home textiles to industrial materials, ramie is proving to be a versatile, renewable resource that helps reduce waste and promote sustainability.

Understanding Ramie and Its Botanical Origin

Ramie, derived from the Boehmeria nivea plant, is a highly sustainable and renewable bast fiber known for its strength, durability, and luster.

Grown mainly in warm, humid climates, ramie fibers are rich in cellulose, making them exceptionally strong, moisture-absorbent, and resistant to heat and microbial decay. Unlike other natural fibers such as cotton, flax, and jute, ramie offers superior tensile strength and a silk-like sheen, while also being highly absorbent, making it ideal for breathable textiles.

 Its ability to regrow rapidly after each harvest and its minimal impact on soil health make it a valuable resource for sustainable material development and crop rotation systems. Ramie’s unique combination of physical properties ensures its continued relevance in a wide range of applications, from textiles to bio-based products.

Processing Stages for Bio-Based Ramie Products

Producing bio-based materials from ramie involves separating, cleaning, and converting plant fibers into usable forms. Here are the details.

• Decortication Methods
• Degumming: Chemical and Enzymatic Techniques
• Spinning and Weaving
• Advances in Ramie Processing Technology

1. Decortication Methods

Decortication removes the fibrous bark (bast) from the woody core of the ramie stalk. Small-scale operations often rely on manual peeling, which is slow (about 10 kg of bast per day per worker). Mechanical decorticators, which use rollers, blades, or drums, speed up the process and maintain fiber quality. Planetary decorticators, such as the one developed by Slimani et al. (2018), use rotating agitators to minimize fiber breakage, thereby improving yield without compromising quality. Modern systems utilize automated conveyors and adjustable rollers to reduce labor and ensure consistent fiber width for better spinning.

Method	Throughput (kg/h)	Fiber Damage	Labor Needs	Typical Uses
Manual	< 20	Low	High	Small farms
Roller-based	80–120	Moderate	Medium	Regional mills
Planetary	150–200	Low	Low	Industrial plants

2. Degumming: Chemical and Enzymatic Techniques

Degumming removes non-cellulosic materials (such as pectin and lignin) that bind the fibers. Traditional chemical degumming uses alkaline solutions, which consume large amounts of water and cause significant pollution. Newer methods, such as oxidative and solvent-based degumming, reduce chemical use and improve efficiency, but enzyme-based degumming has become increasingly popular. Enzymes such as pectinase and hemicellulase selectively break down gums without damaging the cellulose, thereby preserving fiber strength. This method reduces chemical use by 50% and cuts energy consumption by over 20%, although it takes longer to complete. Researchers are working to speed up the process through temperature and agitation control.

3. Spinning and Weaving

After degumming, ramie fibers are carded and combed to align them and remove short fibers (called “noils”). These noils, which can account for up to 40% of the fiber mass, are too short for fine yarns but can be used in nonwoven fabrics or composites. Spinning methods such as stretch-breaking and compact spinning improve yarn quality by making the fibers more uniform and reducing hairiness. Weaving follows standard textile techniques to create breathable fabrics with good stability. Ramie fibers also resist microbial growth, so they require fewer chemicals during finishing, making the process more eco-friendly.

4. Advances in Ramie Processing Technology

Research has focused on improving efficiency and sustainability. Automation in decortication reduces manual labor and ensures consistent fiber thickness. In degumming, mixed-enzyme systems accelerate the process and enable water reuse, thereby reducing waste. Spinning innovations, such as compact and Siro spinning, reduce yarn irregularities and improve strength at lower twist levels. These advances help make ramie more efficient and environmentally friendly while maintaining its performance in bio-based products.

Material Properties and Performance

Ramie-based materials exhibit a consistent balance between strength, stiffness, and chemical stability compared to other natural fibers. Their properties and performance are as follows.

• Mechanical Properties and High Tensile Strength
• Fiber Length and Uniformity
• Durability and Longevity

1. Mechanical Properties and High Tensile Strength

Ramie fibers exhibit high tensile strength (typically 400–938 MPa) due to their high cellulose crystallinity and the alignment of microfibrils within the fiber wall. Because of this alignment, the fibers resist stretching under tension and efficiently transfer loads in composite materials. In practice, this results in stronger reinforcement when ramie is embedded in resins such as epoxy or polyurethane systems.

Tests show that ramie-reinforced epoxy composites achieve up to a 29 % increase in flexural strength compared to neat epoxy matrices. This improvement occurs because the hydroxyl groups on the surface of ramie enhance interfacial bonding when properly treated or coated. For users, this means that structures made with ramie composites—such as panels, casings, or molded components—maintain rigidity while weighing less than glass-fiber alternatives.

2. Fiber Length and Uniformity

Ramie fibers range in length from 60 mm to 250 mm, with diameters of 18–30 µm. Their uniform structure and smooth surface improve fiber packing and stress distribution within composites. Longer fibers provide better tensile load transfer, while shorter, uniform fibers allow for easier mixing and predictable mechanical performance.

During processing, controlling fiber uniformity reduces the occurrence of weak zones during weaving or composite lamination. When fibers are evenly spaced and combed, the matrix bonds more consistently, preventing stress concentration points. In manufacturing, this results in lower rejection rates and more stable product performance.

A simplified comparison illustrates the importance of length:

Fiber Type	Average Length (mm)	Common Uses	Key Effect on Strength
Ramie	150–250	Composites, Textiles	High load transfer
Jute	100–150	Bags, Ropes	Moderate strength
Flax	250–300	Linen, Composites	Balanced Stiffness

3. Durability and Longevity

Ramie fibers are durable due to their high cellulose content (over 70 %) and low elastic recovery, which limits creep under constant stress. The fiber’s lignin and pectin layers provide resistance to microbial decay, and alkali or silane surface treatments further enhance water and thermal stability.

When incorporated into bio-based epoxy resins, ramie maintains its strength after repeated thermal cycling and exposure to humidity. For end users, this means that ramie composites can withstand repeated mechanical loads without rapid degradation or delamination. In humid climates or high-temperature environments, such as automotive interiors, ramie’s natural resistance to dimensional changes helps maintain part alignment and structural integrity over time.

Environmental Impact

Ramie production has an impact on the environment at various stages, from cultivation to fiber processing. The details are as follows:

1. Biodegradability and Eco-Friendly Characteristics

Ramie fibers are biodegradable because they are primarily composed of cellulose and have a low lignin content, allowing them to break down naturally without harming the environment. When disposed of in soil or compost, ramie decomposes into organic matter and carbon dioxide within months. Ramie also grows with fewer chemicals, requiring little pesticide and improving soil health. This makes ramie textiles eco-friendly, meeting eco-label standards and reducing waste in landfills and oceans.

2. Waste and Emissions from Processing

The primary environmental impact of ramie stems from the degumming process, which removes natural gums using strong alkalis and large amounts of water. Traditional methods generate a significant amount of wastewater, making treatment costly and energy-intensive. New biological degumming methods, which utilize enzymes, reduce water consumption and chemical waste by over 50%. Additionally, ramie by-products such as stalks and leaves can be repurposed into valuable materials, thereby reducing waste and enhancing sustainability.

3. Sustainability Certifications

Ramie products can meet international sustainability certification standards to demonstrate their eco-friendly performance:

• Oeko-Tex® Standard 100: Ensures that textiles are free of harmful chemicals.
• EU REACH Compliance: Restricts the use of hazardous chemicals in the European Union.
• ISO 14001: Provides guidance on environmental management and efficiency.

These certifications help producers demonstrate responsible practices and gain access to markets that require sustainable materials.

Applications of Bio-Based Ramie Products

Ramie provides renewable plant-based fibers that combine strength, luster, and stability. Its processed forms—including yarns, fabrics, and blended textiles—are used to replace synthetic materials in clothing, interior design, and specialized technical products.

1. Textile Fibers and Ramie Fabrics

Ramie is a strong, durable fiber derived from the stem of the Boehmeria nivea plant. Its high cellulose content gives it tensile strength (500–900 MPa), making it more resistant to stretching and better at retaining its shape after washing. Ramie fabrics have a natural sheen and excellent wet strength, unlike cotton, which weakens when wet. Manufacturers remove pectin and wax during processing, making the fibers finer and improving dye absorption to produce vibrant, uniform colors with less waste.

2. Home Textiles and Technical Textiles

Ramie’s moisture-absorbing and mold-resistant properties make it ideal for home textiles such as curtains, upholstery, and bedding. It absorbs 8–12% of its weight in moisture without feeling damp, which helps fabrics remain comfortable in warm or humid conditions. Ramie’s high crystallinity and resistance to alkalis make it durable, so it performs well in items such as table linens and wall coverings. In technical textiles, ramie is used as a reinforcing material in bio-based composites, such as flame-retardant thermoset composites for automotive and construction components, offering a lighter, renewable alternative to synthetic materials.

3. Performance Fabrics and Blended Textiles

Ramie is often blended with cotton, polyester, or silk to combine strength with comfort. A ramie-cotton blend, for example, combines ramie’s strength with cotton’s softness, creating breathable fabrics for shirts and summer clothing. Ramie blends are less prone to wrinkling and shrinkage, so clothes retain their shape and require less ironing. Ramie-polyester blends offer improved abrasion resistance, making them ideal for outdoor gear, luggage, and sports equipment. These fabrics are more durable and have a natural feel, while also being more sustainable than pure synthetics.

Future Prospects for Bio-Based Ramie Products

The growing global demand for plant-based fibers is driving the use of ramie in sustainable manufacturing, particularly in textiles, bioplastics, and biocomposites.

The ramie supply chain, which connects smallholder farms to manufacturers of bio-based products, faces challenges such as high moisture content and labor-intensive production methods, but traceability platforms are improving transparency for certifications.

The market has strong potential, with the bio-based chemicals sector expected to exceed $160 billion by 2025, although production costs and competition from cheaper fibers remain obstacles.

However, technological advancements such as enzyme-assisted degumming and the development of ramie-reinforced composites offer promising solutions, enhancing ramie’s performance and expanding its applications.

With continued innovation, ramie is poised to become a key player in the circular bioeconomy, providing sustainable alternatives across various industries.

Frequently Asked Questions

What are bio-based fabrics?

Bio-based fabrics use renewable biological materials such as plant fibers, proteins, or biopolymers instead of fossil fuels. Ramie fibers fall into this category because they come directly from a plant stalk that contains about 65–75% cellulose. That high cellulose content makes the fiber naturally stiff and moisture-absorbent.

Because they are made from plant-based materials, these fabrics can partially biodegrade under the right conditions. In practice, this means they reduce reliance on synthetic polymers and limit the long-term accumulation of waste in landfills.

How are ramie fibers used in sustainable fashion?

Ramie fibers are used in clothing, home linens, and industrial threads. Their structure—long, smooth, and highly crystalline—gives them strength and resistance to shrinkage after washing. Because the fibers wick moisture efficiently, garments made from ramie feel dry and comfortable in warm climates.

When blended with cotton or other natural fibers, ramie enhances wrinkle resistance and durability without the addition of plastics. For designers, this means they can create textiles that retain their shape and color while maintaining a natural composition.

Can ramie be used to make bio-based products other than textiles?

Yes. Processing ramie produces residues such as leaves, roots, stalks, and noil fibers. These materials contain cellulose, hemicellulose, lignin, and proteins that can serve as feedstock for bioplastics, paper pulp, or animal feed. For example, decorticated stalks contain approximately 35–44% cellulose and 18–30% lignin, making them suitable for biocomposites and energy materials.

In practice, this means that ramie waste can be used to partially replace the raw materials used in packaging films or molded plant-fiber plastics. By recycling these residues, manufacturers can reduce disposal costs while generating new revenue from materials that would otherwise go unused.