TT: Polylactic Acid (PLA) fibre is emerging as a groundbreaking material in the textile industry. What is the reason?
Derived from renewable plant resources, PLA fibre stands out for its biodegradability, biocompatibility, and impressive performance characteristics. It combines the advantages of natural fibres and chemically synthesised fibres, has a weak acidity similar to human skin, is naturally skin-friendly, antibacterial, anti-mite, and anti-allergic.
TT: Can you tell us about the origins and composition of PLA fibre?
PLA fibre is a synthetic fibre made from renewable plant resources (such as corn starch or sugar cane) through biotechnology processing.
PLA fibre is also known as ‘eco-fibre’, as its raw materials are sourced from renewable plant resources, which reduce the consumption of non-renewable resources such as petroleum in the textile industry to a certain extent, and decrease the emission of greenhouse gases. Moreover, the production process of PLA fibre is also more low-carbon and environmentally friendly. From raw materials to waste, it can be decomposed into carbon dioxide and water in soil or seawater through microbial action, and it does not emit toxic gases when burned, thus not causing pollution. Thus, PLA fibre is an eco-friendly alternative to traditional synthetic fibres.
TT: What are the various categories of PLA fibres?
The commonly used PLA fibres can be divided into two main categories: PLA short staples and PLA filament yarns.
PLA short staple: PLA short staple possesses commendable mechanical properties, including strength and elasticity. These fibres can be spun into pure products or blended with other materials such as cotton, wool, linen, lyocell, and modal fibres. Variants of PLA short staple include PLA staple, PLA super short cut staple, PLA bi-component, three-dimensional crimped staple, coloured spun yarns, and functional fibres. This versatility allows for extensive use across various textile applications.
PLA filament yarn: PLA filament yarn is a collection of fibres formed by stretching, twisting, or deforming multiple long monofilaments. A single strand of filament contains dozens of monofilaments, which is known as PLA composite filament. This can be spun into differentiated PLA fibres. At the same time, it also includes PLA monofilament, which, due to its unique properties, is widely used in fields such as medical sutures, fishing, and tea bags.
TT: How would you describe the performance of PLA fibre?
In addition to good mechanical properties and smooth breathability, PLA fibre also has the following characteristics:
Mechanical Properties: According to test results, the breaking strength of PLA fibres is 3.2~4.9cN/dtex, which is higher than natural cotton fibres. The dry-state breaking elongation rate is similar to nylon and wool, and the elongation rate increases in the wet state, indicating that PLA fibre products have the advantages of high strength and good extensibility.
Biodegradability: Under average temperature and humidity, PLA fibres and their products are stable. When in a natural environment with specific temperature and humidity (such as sand, silt, seawater), microorganisms will completely degrade PLA into carbon dioxide and water. If PLA fibres are buried in the soil, the natural degradation time is 2~3 years; if PLA fibres are mixed and buried with organic waste, they will decompose in a few months.
PLA waste products can be completely decomposed into carbon dioxide and water in industrial composting conditions (temperature 58°C, humidity 98%, and microbial conditions) within 3-6 months, which has a perfect environmental effect.
Biocompatibility, Anti-allergy: PLA comes from lactic acid, which is an endogenous substance in the human body, and the pH value of the fibre is almost consistent with that of the human body, giving PLA fibre good biocompatibility, excellent skin affinity, non-allergenicity, and good product safety performance, thus it can also be widely applied in the biomedical field.
Antibacterial and Anti-mite, Anti-mould and Anti-odour: The surface of PLA fibre exhibits the weak acidity of lactic acid, giving it natural antibacterial properties, effectively inhibiting the growth of mites, and providing anti-mould and anti-odour effects.
Wearability: From drape to thermal insulation, PLA fibre has the following properties:
Drape: PLA fibre has a low initial modulus and a small drape coefficient, giving the fabric good draping properties.
Moisture Absorption and Breathability: PLA fibre has poor moisture absorption but good breathability.
Crease Recovery: PLA fibre has an elastic recovery rate of up to 93 per cent when stretched by 5 per cent, so pure PLA fibre fabrics have good crease recovery.
Abrasion Resistance and Pilling: PLA fibre has slightly better abrasion resistance than polyester, but the fabric has pilling phenomena.
Thermal Insulation: PLA fibres offer superior thermal insulation compared to cotton and polyester, making them suitable for different seasons.
Other Properties: PLA fibres have good UV resistance, and are self-extinguishing, emit low smoke, and non-toxic.
TT: What are the various applications of PLA fibre?
PLA fibre’s unique properties make it suitable for a wide range of applications across different industries:
Sanitary Materials: PLA nonwoven fabric has a smooth surface, does not absorb moisture, and has better fluidity, dryness, biocompatibility, and non-allergenicity, making it more suitable for people prone to allergies. It can be widely used in related fields of sanitary materials, such as the surface layer, diversion layer, and bottom layer of sanitary napkins and paper diapers, makeup remover cotton, wet wipes, face towels, membrane cloth, and other disposable sanitary products.
PLA fibre can meet the antibacterial requirements of disposable medical and sanitary products and solve the ‘white pollution’ problem caused by disposable medical and sanitary products due to its biodegradability.
Apparel Fabrics: PLA fibre has physical properties similar to polyester/polyester materials, can be shaped, has good strength and dimensional stability, does not irritate the skin, is easy to wash and dry, and can also be functionalised by changing the process during spinning and adding other materials, such as moisture absorption and perspiration, UV protection etc, thus developing uniquely advantageous apparel fabrics.
Home Textiles and Toy Fillings: For fillings for quilts and pillows, hollow PLA short fibres can be used. These can be pure PLA or blended with other fibres, replacing existing polyester-related fillers.
For bedding fabrics (interwoven, blended, etc), the advantages of PLA fibres like being skin-friendly, non-irritating, non-allergenic, overcoming the shortcomings of polyester/cotton fabrics, having better dimensional stability than all-cotton fabrics, and being easy to wash, dry, and care for can be fully utilised.
Medical Supplies: These fibres can be used for masks, protective clothing, medical gauze, bandages, sheets, and high-end antibacterial products etc.
Agriculture: In agriculture, PLA fibres are used to create mulch films and seed blankets that protect crops while reducing the need for chemical fertilisers and pesticides. These products naturally decompose, enriching the soil instead of polluting it.
Other Applications: In addition, these fibres have other applications in packaging materials, sand barriers, filter bundles, decorative board adhesives, etc.
TT: How do you see the future of PLA fibre?
PLA fibre represents a significant advancement in sustainable textiles, offering a compelling combination of environmental friendliness and high performance. As industries continue to prioritise eco-friendly materials, PLA fibre is poised to play a crucial role in the future of textiles and nonwoven fabrics. With ongoing advancements and increasing adoption, PLA fibre is set to revolutionise various sectors, contributing to a more sustainable and environmentally conscious world.
TT: Tell us about your company EsunFiber.
EsunFiber (Suzhou) Co., Ltd. was founded in 2000 under the name of Changshu Changjiang Chemical Fiber Co., Ltd. In 2015, it became part of the Hi-Tech Fiber Group Corporation and was renamed Hi-Tech Changjiang PLA Co., Ltd. In December 2023, we rebranded as EsunFiber (Suzhou) Co., Ltd.
EsunFiber focuses on developing and strategically expanding polylactic acid fibre and nonwoven fabrics as main products.
TT: What is your production capacity?
EsunFiber has one 10,000 tons/year bi-component polylactic acid fibre production line, one 1,000 tons/year polylactic acid hot air nonwoven fabric production line, and three functional polylactic acid fibre production lines. Among them, the three functional polylactic acid fibre production lines have an annual capacity of 5,000 tons and can produce various differentiated products such as three-dimensional curled fibres, dual-component PLA fibres, profiled fibre, polylactic acid yarn, and solution-dyed polylactic acid fibres.
TT: Anything that you would like to add, for example, on certification?
EsunFiber’s PLA fibre has passed the German DIN compostable certification and the American BPI degradable certification. Our PLA fibres have also obtained the OEKO-TEX STANDARD 100 Certification. We have mastered the chemical recycling technology of PLA and have industrialised it, which can establish a green closed-loop industrial chain for the production of PLA fibre products, further realising the efficient recycling and utilisation of resources.