Application of Different Types of Polyvinyl Alcohol Pva

Polyvinyl alcohol abbreviated as PVA,PVOH,cas 9002-89-5, is a very widely used chemical material, can be used in textile pulp, vinylon fiber, paper coating agent, architectural coatings, polyvinyl alcohol surfactant, adhesives, PVA film, PVB raw materials, food and medicine, PVA can also be used as Soil conditioner, polymeric suspending agent and emulsifier, quenching agent, etc. In addition, as people continue to develop and improve the performance of PVA, its use is constantly expanding.

Polyvinyl alcohol resin is produced from ethylene vinyl acetate as raw material by solution polymerization and anhydrous low alkali alcoholysis. The process has the characteristics of low material consumption, low energy consumption, low pollution, is an environmentally friendly product, polyvinyl alcohol mainly has the main alcoholysis type and part of the alcoholysis type two categories.

Polyvinyl alcohol (PVA) each type of use

1. Vinylon raw materials: polyvinyl alcohol after dissolution, spinning, and then acetalized treatment can be made of vinylon fiber, it can be mixed with cotton, wool, viscose fibers and other products made of vinylon textiles, widely used in clothing, cloth, cord, fishnet rope, etc.. Generally, the average degree of polymerization of 1750 ± 50, that is, PVA17-99 as spinning raw materials.

2. Warp pulp: A. polyvinyl alcohol-based modulation of the pulp, cotton, hemp, polyester, vinyl viscose fiber has good adhesion, film after the smooth, both strong and wear-resistant, to promote the warp yarn weaveability, reduce the weaving process due to warp friction, bending. Stretching and other intense movement caused by warp yarn breakage, reduce the rate of machine breakage. And the woven cloth feels firm. Smooth and delicate, the surface of the cloth is not rough. B. polyvinyl alcohol is water-soluble polymer compounds, sizing, sizing, desizing are very convenient. c, generally choose the average polymerization degree of low polyvinyl alcohol (such as PVA15-99, 16-99, 17-99) for the slurry.

3. Adhesives: A. polyvinyl alcohol aqueous solution of materials containing cellulose (such as paper, cloth, wood, etc.) is extremely strong adhesion, has the advantage of safety and non-toxic, can be used for cardboard laminated, corrugated cardboard bonding and office glue, etc.. Packaging heavy materials such as cement, fertilizer, grain, etc. with kraft paper bags also use PVA as an adhesive. B. modified with polyvinyl alcohol urea-formaldehyde resin and phenolic resin can be used as a laminate and man-made board adhesives. C. polyvinyl alcohol aqueous solution (by adding appropriate fillers, additives) is also widely used in the preparation of printing and binding, paper tubes, cartons and other paper products required for adhesives. D. polyvinyl alcohol in acid-catalyzed, and formaldehyde, butyraldehyde, glyoxal or other aldehydes condensation, can produce a stronger water resistance, adhesion, mechanical strength of polyvinyl alcohol acetal (such as PVAF, PVB) is widely used in building construction, coatings, adhesives, safety glass lamination and other fields. With PVA polymerization degree increases, acetal viscosity increases. E. polyvinyl alcohol is vinyl acetate homopolymerization or copolymerization with other monomers to produce emulsions (white glue) of excellent protective colloid and dispersant, in the production of white glue is essential. Generally, as the polymerization degree of polyvinyl alcohol increases, the viscosity of the produced emulsion increases. Partially alcoholic polyvinyl alcohol (17-88) and fully alcoholic polyvinyl alcohol (such as 17-99, 19-99, etc.) are mostly used together, using partially alcoholic polyvinyl alcohol can increase the stability of emulsions, using fully alcoholic polyvinyl alcohol can increase the water resistance of emulsions.

4. Paper processing: A. polyvinyl alcohol in the paper industry can be used as a paper surface sizing agent, with good film formation, high film strength characteristics, can improve the paper printing adaptability, smoothness, friction resistance, folding resistance, oil resistance and chemical resistance. Choose the average polymerization degree of 1750 ± 50 PVA for paper surface sizing agent. B. pigment processing agent: can improve the whiteness and gloss of coated paper, good printing gloss, sharp color and luster, improve paper quality. Choose the average polymerization degree of high polyvinyl alcohol. C. as paper sizing agent: papermaking, adding powdered polyvinyl alcohol and pulp together with the pulp, paper, so that the resulting paper strength. Choose the average polymerization degree of high polyvinyl alcohol.

5. Polyvinyl alcohol film: The film made of this product has good transparency, high tensile and cracking strength, good moisture permeability and gas barrier, oil resistance, organic drug resistance, and no static electricity, so it is suitable for textile packaging. In addition, it can be laminated with polyethylene and polypropylene.