How does bamboo fiber spunlace nonwoven fabric meet the demand for environmentally friendly materials through its process and performance advantages?

As global environmental awareness grows, traditional materials have been criticized for being non-degradable and polluting the environment. The research and development and application of new environmentally friendly materials have become the focus of the industry. Bamboo fiber spunlace nonwovens have emerged in the field of environmentally friendly materials with their unique process and excellent performance.

Analysis of the core technology of bamboo fiber spunlace nonwoven fabric

(1) Strengthening effect of hydroentanglement technology on fiber structure

As a key process in the production of bamboo fiber spunlace nonwovens, the principle of hydroentanglement technology is based on the impact force of high-pressure water flow. During the production process, the pre-treated bamboo fibers are laid on the conveyor net in a fluffy and messy mesh. Tens of thousands of tiny water needles on the high-pressure water needle plate are vertically sprayed at the fiber net at a pressure of up to tens of megapascals. These high-speed water flows are like countless tiny "flexible needles" that quickly penetrate the fiber net, causing the fibers to entangle and embrace each other.

The strengthening effect of hydroentanglement technology on fiber structure is reflected in many aspects. From the perspective of microstructure, during the hydroentanglement process, the fibers are displaced, interlaced and entangled under the impact of water flow, and the originally loose fibers gradually form a tight three-dimensional network structure. This structure significantly increases the friction and cohesion between the fibers, thereby improving the strength and toughness of the non-woven fabric. For example, the breaking strength of the hydroentangled bamboo fiber hydroentangled non-woven fabric can be increased by 2-3 times compared to the untreated fiber mesh, which effectively enhances the durability of the material.

In actual production, the spunlace process parameters have an important influence on the fiber structure and non-woven fabric performance. Spunlace pressure is one of the key parameters. If the pressure is too small, the fibers are not fully entangled and the non-woven fabric has low strength. If the pressure is too high, it may cause fiber damage and affect its performance. Generally speaking, the spunlace pressure needs to be precisely adjusted according to factors such as the type, length, and fineness of the fiber. In addition, parameters such as the number and arrangement of spunlace heads and the number of spunlace passes will also affect the fiber entanglement effect and the uniformity of the non-woven fabric. By rationally optimizing these parameters, bamboo fiber spunlace non-woven fabric products that meet different application requirements can be produced.

(2) Key indicators for bamboo pulp raw material screening and pretreatment

The quality of bamboo pulp raw materials directly affects the performance of bamboo fiber spunlace non-woven fabrics, so raw material screening is crucial. In the process of bamboo pulp raw material screening, bamboo species, growth environment and growth cycle are the main considerations. Different varieties of bamboo have different chemical composition and physical properties. For example, moso bamboo fiber is slender and strong, suitable for the production of high-strength non-woven products; cycad bamboo fiber is soft and delicate, more suitable for fields with high tactile requirements. Bamboo grows in an environment with sufficient sunshine, abundant rain and fertile soil, and its fiber quality is often better. At the same time, the growth cycle of bamboo also needs to be appropriate. Generally, 3-5 year-old bamboo has high fiber content and good quality, which is an ideal raw material choice.

In addition to the variety, environment and cycle, the fiber length, fineness and purity of bamboo pulp raw materials are also key indicators. Longer, finer and purer fibers can form a more uniform and dense fiber web, which is beneficial to improve the strength, softness and breathability of non-woven fabrics. Generally, the length of high-quality bamboo pulp fibers is between 1-3 mm, the fineness is about 1.5-3 denier, and the purity should reach more than 95%.

Pretreatment of bamboo pulp is also indispensable. Pretreatment mainly includes cooking, bleaching, beating and other processes. Cooking is to react bamboo raw materials with chemical agents under high temperature and pressure to dissolve impurities such as lignin and separate fibers. The cooking process parameters need to be precisely controlled. Too high temperature or too long time will lead to excessive fiber degradation and reduce strength; too low temperature or insufficient time will not completely remove impurities. The purpose of bleaching is to remove pigments and residual impurities in the fiber and improve the fiber whiteness, but excessive bleaching will damage the fiber and affect its performance. Pulping is to separate the fiber into filaments through mechanical action, increase the specific surface area and flexibility of the fiber, and make it easier for the fibers to entangle, thereby improving the physical properties of the non-woven fabric. The appropriate beating degree is generally controlled between 25-45°SR to ensure the good performance of the fiber and the quality of the non-woven fabric.

Differentiated performance of bamboo fiber spunlace nonwovens

(1) Comparison of experimental data on antibacterial properties, breathability and degradability

Bamboo fiber spunlace nonwoven fabrics have excellent antibacterial properties. Studies have shown that bamboo fiber contains a natural antibacterial substance called "Zhukun", which has a significant inhibitory effect on common pathogens such as Escherichia coli, Staphylococcus aureus, and Candida albicans. Relevant experimental data show that under the same experimental conditions, the antibacterial rate of bamboo fiber spunlace nonwoven fabrics on Escherichia coli can reach more than 98%, and the antibacterial rate on Staphylococcus aureus is more than 95%, while ordinary PP nonwoven fabrics have almost no antibacterial ability. This excellent antibacterial property gives it a wide range of application prospects in the fields of medical and sanitary products.

In terms of air permeability, bamboo fiber spunlace nonwoven fabric is also superior to many traditional materials. Due to its unique fiber structure and the porous structure formed by the spunlace process, air can flow freely. Experimental tests show that the air permeability of bamboo fiber spunlace nonwoven fabric can reach 300-500mm/s, while the air permeability of traditional PP nonwoven fabric is only 100-200mm/s. Good air permeability allows it to keep the skin dry and comfortable when used in medical and sanitary products, clothing fabrics and other fields, effectively improving the product experience.

Degradability is an important characteristic of bamboo fiber spunlace nonwovens to meet environmental protection needs. In the natural environment, bamboo fiber can be decomposed into carbon dioxide and water by microorganisms, and will not pollute the environment. Degradation experiments simulating natural environments show that bamboo fiber spunlace nonwovens can be completely degraded in soil in 6-8 months, while traditional PP nonwovens can degrade for hundreds of years or even longer under the same conditions. This rapid degradation characteristic makes bamboo fiber spunlace nonwovens have great application potential in environmentally friendly packaging, agricultural mulch and other fields, which helps to reduce white pollution and promote sustainable development.

(2) Differences in physical performance parameters compared to traditional PP nonwovens

In terms of physical properties, bamboo fiber spunlace nonwovens are significantly different from traditional PP nonwovens. In terms of strength performance, although PP nonwovens have a certain tensile strength, bamboo fiber spunlace nonwovens have better breaking strength and tearing strength after being treated with optimized spunlace technology. For example, at the same gram weight, the breaking strength of bamboo fiber spunlace nonwovens can reach 15-20N/5cm, while the breaking strength of PP nonwovens is about 10-15N/5cm. In terms of toughness, bamboo fiber spunlace nonwovens have better resilience and are not easy to deform, while PP nonwovens are prone to permanent deformation after repeated stretching.

In terms of softness, the softness of bamboo fiber itself makes bamboo fiber spunlace nonwoven fabric feel more delicate and soft. According to the test, the bending stiffness of bamboo fiber spunlace nonwoven fabric is 0.1 - 0.2cN・cm²/cm, while the bending stiffness of PP nonwoven fabric is 0.3 - 0.4cN・cm²/cm, which is significantly higher than bamboo fiber spunlace nonwoven fabric and feels relatively hard. In addition, bamboo fiber spunlace nonwoven fabric also has good hygroscopicity, and its water absorption rate can reach 5 - 8 times its own weight, while PP nonwoven fabric has a water absorption rate of only 0.1 - 0.3 times its own weight due to its hydrophobicity. The differences in these physical performance parameters determine that bamboo fiber spunlace nonwoven fabric has unique advantages in different application scenarios.

Discussion on technical adaptability in application scenarios

(1) Requirements for liquid absorption and biocompatibility in the medical and health care field

In the field of medical and sanitary materials, bamboo fiber spunlace nonwovens need to meet strict requirements for liquid absorption and biocompatibility. Liquid absorption is one of the important performance indicators of medical and sanitary materials, and is particularly critical for products such as wound dressings, surgical towels, and sanitary care pads. Bamboo fiber spunlace nonwovens can quickly absorb and lock liquids due to their good hygroscopicity and unique porous structure. Experimental data show that in tests simulating wound exudate, the liquid absorption speed of bamboo fiber spunlace nonwovens can reach 1-2 seconds/100mm, and the liquid absorption amount can reach 10-15 times its own weight, which can effectively keep wounds dry and promote wound healing.

Biocompatibility is also a must-have property for medical and health materials. Bamboo fiber is a natural plant fiber that has good compatibility with human tissue and does not cause adverse reactions such as allergies and irritation. After strict sterilization, bamboo fiber spunlace nonwovens can be safely used in the medical field. In clinical applications, wound dressings made of bamboo fiber spunlace nonwovens can reduce the risk of wound infection and accelerate the wound healing process, which has been widely recognized by medical staff and patients. In addition, the antibacterial properties of bamboo fiber can effectively inhibit the growth of bacteria around the wound, further ensuring the healing environment of the wound.

(2) Balance between strength and degradation cycle of environmentally friendly packaging materials

In the field of environmentally friendly packaging materials, bamboo fiber spunlace nonwovens need to find a balance between strength and degradation cycle. On the one hand, packaging materials need to have sufficient strength to protect products from damage during transportation and storage. The strength of bamboo fiber spunlace nonwovens can be improved by optimizing spunlace process parameters and adjusting fiber ratios. For example, increasing the number of spunlace passes and increasing spunlace pressure can enhance the entanglement between fibers and improve the overall strength of the nonwoven fabric; appropriately adding other high-strength fibers, such as polyester fibers, to bamboo fibers can also improve their mechanical properties.

On the other hand, in order to meet environmental protection requirements, the degradation cycle of packaging materials cannot be too long. By controlling the pretreatment process of bamboo fiber and adding degradable additives, the degradation rate of bamboo fiber spunlace non-woven fabrics can be adjusted. For example, appropriately increasing the beating degree to make the fiber finer can increase the contact area between microorganisms and fibers and accelerate the degradation rate; adding degradable additives such as starch base can promote the decomposition of non-woven fabrics in the natural environment. In practical applications, according to the use cycle and storage conditions of different packaging products, the formula and process of bamboo fiber spunlace non-woven fabrics are reasonably designed to achieve the best balance between strength and degradation cycle, which can not only ensure the packaging function but also reduce the impact on the environment.

In summary, bamboo fiber spunlace nonwovens fully meet the demand for environmentally friendly materials with their unique core technology, excellent differentiated performance and good technical adaptability in different application scenarios. With the continuous advancement of technology and the expansion of application fields, bamboo fiber spunlace nonwovens are expected to play a greater role in the environmentally friendly materials market and make important contributions to sustainable development.