Polyvinyl alcohol (PVA) fibers, also known as PVA fibers, are a type of synthetic fiber made from high-polymerized polyvinyl alcohol (PVA) using specific advanced technology.

Vinyl Alcohol Fibers are characterized by high strength and modulus, low elongation, excellent wear resistance, and good resistance to acids and alkalis, along with superior weather resistance. They have good affinity and bonding properties with substrates like cement and gypsum, and are non-toxic, pollution-free, and safe for human skin without causing harm. They are among the green building materials of the new generation of high technology. The raw material for producing Vinyl Alcohol Fibers is polyvinyl alcohol, a water-soluble high polymer with properties between plastics and rubbers, and has a wide range of applications.

Polyvinyl alcohol (PVA) fiber is made from raw PVA with an average molecular weight of 60,000 to 150,000, a thermal decomposition temperature of 200 to 220°C, and a melting point of 225 to 230°C. PVA fiber can be produced through both wet spinning and dry spinning. Heat-treated PVA fiber can be processed into PVA-formaldehyde copolymer fiber through acetalization. The acetalization process involves washing the fiber bundle to remove gypsum (sodium sulfate) and then passing it through a solution of formaldehyde (acetalizing agent), water (diluent), sulfuric acid (catalyst), and sodium sulfate (anti-swell agent). It can also be cut into short fibers, transported to the post-processing machine via air, and acetalized on a stainless steel mesh. To enhance fiber properties, a PVA solution containing boron trifluoride cross-linking agent (16% concentration) can be used for wet spinning. The resulting primary fiber is solidified in an alkaline coagulation bath, followed by neutralization, washing, multi-stage high-velocity stretching, and heat treatment, resulting in a long fiber with a strength of 106 to 115 cN/dtex.