Functional fiber | Why soy protein fiber is becoming more and more popular!

Soy protein fiber

Soy protein fiber (PVA-SPF) is a new high-tech, high value-added textile raw material pioneered in my country. Since the main component of this fiber is soybean protein, and the auxiliary materials and additives used are non-toxic, it is known as the “green and environmentally friendly fiber” in the new century. This fiber not only has the feel of cashmere, the luster of silk, the hygroscopicity and moisture conductivity of cotton fiber, but also has the mechanical properties of synthetic fiber.

The emergence of soy protein fiber caters to the needs of ecological environmental protection and people’s demand for clothing The pursuit of wearing comfort, functionality and aesthetics makes it a new textile material with great potential and development prospects.

Soy protein fiber spinning process

Using soybean waste meal after oil extraction as raw material, using biotechnology to purify the globulin in soybean meal and using additives The action of biological enzymes changes the spatial structure of the purified globulin, and then adds high polymers such as hydroxyl and amino groups to prepare a protein spinning solution of a certain concentration. After maturation, it is spun into single fibers with a wet spinning process of 0.9~ After the 3dtex tows are formaldehylated to stabilize the properties of the fibers, they are then crimped, heat set, and cut to produce high-grade fibers for textile use in various specifications.

The production process of soy protein fiber mainly relies on bioengineering technology to improve traditional fibers. According to relevant data analysis, the majority of soybeans after oil extractionBean cake contains protein and is usually used only as fertilizer. However, after chemical processing, protein can be extracted from soybean cake and made into soy protein fiber, which greatly improves the use efficiency of soybean cake. Its production process does not pollute the environment, and the product waste is easily biodegradable and is green and environmentally friendly.

Structure of soy protein fiber

Physical structure

The cross-section of soy protein fiber is dumbbell-shaped or waist-round, with micropores in the middle, obvious skin-core structure, and the cortex is quite thick, with a certain Anti-deformation properties.

The longitudinal cross-sectional shape is irregular grooves and island-like concavities, which is conducive to moisture absorption and moisture conduction of the fiber , breathable, heat transfer.

Chemical structure

Soy protein fiber is composed of two components: polyvinyl alcohol and soy protein.

Polyvinyl alcohol is a carbon chain polymer, and the macromolecules are connected in a carbon-carbon chain. Its molecular chain It contains a large number of hydroxyl groups, with an average of 1400-1800 per macromolecule. Due to the polarity of the hydroxyl group, the flexibility of the carbon molecular chain is reduced, making it a relatively rigid macromolecule.

Soy protein is a natural heterochain polymer. The macromolecules are connected to each other by amide bonds. The chain segments are small in length and are flexible chains. Since soy protein macromolecules have larger branched chains, the conformation of the macromolecules is α-helical. Protein is easily denatured under many conditions such as tension, moisture and heat, and the denatured soy protein molecular chain is stretched to form a linear β-chain.

Performance of soy protein fiber

Friction properties

Soy protein fiber The friction coefficient is very small, especially the dynamic friction coefficient, which is only 0.052. Therefore, the fabric woven with soy protein fiber is smooth and soft.

Breathability

The following table compares the breathability of soy protein fiber with other fibers

By It can be seen from the table that the air permeability is: soy protein > silk > acrylic > polyester > nylon > polypropylene. The soy protein knitted fabric has the largest air permeability, the best air permeability, and the smallest moisture resistance.

Mechanical properties

Compared with wool, cotton, and silk, soybean fiber has higher breaking strength. In addition, soy protein fiber has a high initial modulus and low boiling water shrinkage, and has strong stability. Under normal washing conditions, the fabric shrinks less, has strong wrinkle resistance, is easy to absorb and quick-drying.

Chemical properties

Glass transition temperature of soy protein fiber��81 ℃, decomposition temperature is 330 ℃, thermal stability is worse than wool. The thermal shrinkage of soy protein fiber in dry hot air and boiling water is higher than that of wool, indicating poor wet and heat dimensional stability. After being irradiated with ultraviolet light for 120 hours, the strength of soybean protein fiber decreased by 9.8%, and the elongation at break and coefficient of variation increased slightly, indicating that soybean protein fiber has better sunlight resistance.

Products based on these properties of soy protein fiber can not only have excellent properties such as moisture conduction and breathability like traditional fabrics such as silk, but also will not cause harm to the skin when worn close to the body, nor will they cause adverse symptoms such as allergies, and can be used as high-end products. Raw material for fabrics.

Soy protein Fiber materials are good materials worth promoting, whether in terms of their intrinsic properties, economic value, or their role in promoting the traditional textile industry. Soy protein fiber has properties such as breathability and smoothness. When mixed with other materials such as silk or cotton, other materials also have excellent properties similar to soy protein fiber. Therefore, soy protein fiber products are becoming more and more popular. With the continuous deepening of research, its utilization value will be continuously developed, the market will continue to expand, and the application prospects are very promising.