What is the moisture absorption of PLA fiber?

PLA, or polylactic acid, is a biodegradable and bioactive thermoplastic polyester derived from renewable resources such as corn starch, tapioca roots, or sugarcane. In recent years, PLA fiber has emerged as a promising alternative to traditional synthetic fibers due to its eco - friendly nature. However, understanding the moisture absorption of PLA fiber is crucial for its various applications.

What is Moisture Absorption?

Moisture absorption refers to the ability of a material to take in and retain moisture from its surrounding environment. It is usually expressed as a percentage of the weight of the absorbed moisture to the dry weight of the material. For fibers, moisture absorption is an important property as it can significantly affect the comfort, durability, and performance of the final textile product.

Moisture Absorption of PLA Fiber

The moisture absorption of PLA fiber is relatively low compared to natural fibers like cotton and wool. The inherent chemical structure of PLA is one of the main factors contributing to this property. The polymer chains in PLA are hydrophobic, meaning they have a natural aversion to water. As a result, PLA fiber has a moisture regain of around 0.4 - 0.6% under standard atmospheric conditions (temperature of 20°C and relative humidity of 65%). This is in stark contrast to cotton, which has a moisture regain of approximately 8 - 9%.

The low moisture absorption of PLA fiber has several implications for its applications. On one hand, it makes PLA fiber suitable for products where moisture resistance is required. For example, in outdoor clothing, PLA fiber can help keep the wearer dry by repelling water and preventing the growth of mold and mildew. The low moisture absorption also means that PLA - based textiles dry quickly after being wet, which is a significant advantage in many practical situations.

On the other hand, the low moisture - absorbing ability can pose some challenges. In applications where breathability is crucial, such as in sportswear, the low moisture absorption may lead to a feeling of discomfort. When the body sweats, the lack of moisture - absorbing capacity in PLA fiber can cause the sweat to accumulate on the surface of the fabric rather than being absorbed and evaporated, resulting in a sticky and uncomfortable sensation.

Factors Affecting the Moisture Absorption of PLA Fiber

Several factors can influence the moisture absorption of PLA fiber.

1. Temperature: Generally, as the temperature increases, the kinetic energy of water molecules in the air also increases. This makes it easier for water molecules to penetrate the fiber structure. As a result, the moisture absorption of PLA fiber tends to increase with rising temperature.
2. Humidity: Higher relative humidity means there are more water molecules in the air. PLA fiber will absorb more moisture in a high - humidity environment compared to a low - humidity one. For instance, in a tropical climate with high humidity, the moisture absorption of PLA fiber may be slightly higher than the standard value.
3. Fabric Structure: The structure of the fabric made from PLA fiber also matters. A more open - weave fabric allows air and moisture to pass through more easily, which can increase the effective moisture exchange between the fabric and the environment. In contrast, a tightly - woven fabric may restrict the access of moisture to the fiber, reducing the moisture absorption.
4. Additives and Surface Treatments: The addition of certain additives or surface treatments can modify the moisture absorption characteristics of PLA fiber. For example, hydrophilic additives can be incorporated into the fiber during the spinning process to increase its ability to absorb moisture. Similarly, surface treatments such as plasma treatment can alter the surface energy of the fiber, making it more receptive to water molecules.

Applications of PLA Fiber Based on Moisture Absorption

1. Packaging: Due to its low moisture absorption, PLA fiber is an ideal choice for packaging applications. It can protect the contents from moisture - induced damage, especially for products that are sensitive to humidity, such as electronics and certain food items.
2. Geotextiles: In geotextile applications, where the material needs to maintain its strength and integrity in different environmental conditions, the low moisture absorption of PLA fiber is beneficial. It can prevent the fiber from weakening due to excessive moisture absorption, ensuring long - term performance in soil reinforcement, erosion control, and drainage systems.
3. Medical Textiles: In some medical applications, the low moisture absorption of PLA fiber can be an advantage. For example, in surgical drapes and wound dressings, it can help prevent the growth of bacteria, which thrive in moist environments. However, this property may need to be balanced with the need for some degree of breathability to promote wound healing.

As a PLA Fiber supplier, we are committed to providing high - quality PLA fiber products suitable for various applications. Whether you are looking for a moisture - resistant solution for outdoor products or exploring new uses in the medical field, our PLA fiber can meet your needs.

We also offer a range of other specialty fibers, including Flame Retardant Polyester Staple Fiber, Low Melt Polyester Fiber, Bosilun Fiber, and Virgin Polyester Tops. You can learn more about our PLA Fiber on our official website.

If you are interested in our products and want to discuss your specific requirements for purchasing and cooperation, please feel free to reach out. We look forward to working with you to find the best fiber solutions for your projects.

References

• "Biodegradable Polymers and Sustainable Fibers" by X. Zhang and Y. Wang.
• "Textile Science and Technology: Fibers, Yarns, and Fabrics" edited by A. Abdel - Khalil.
• Journal articles on PLA fiber properties and applications from journals such as "Journal of Applied Polymer Science" and "Carbohydrate Polymers".