Polyvinyl alcohol

　　(1) Textile Industry

　　Textile Sizing Agents:

　　Used as warp sizing agents to improve yarn abrasion resistance and weavability, replacing traditional starch sizing agents (easy to desize, better environmental performance). Low alcoholysis degree PVA sizing agents can be desized in room temperature water, reducing energy consumption; high alcoholysis degree PVA is used for high-count yarns (such as silk, synthetic fibers).

　　Finishing Agents:

　　Used for anti-static and anti-wrinkle finishing of fabrics to improve hand feel (hydroxyl groups absorb moisture, reducing the coefficient of friction).

　　(2) Food and Pharmaceuticals

　　Food Packaging:

　　Water-soluble PVA films are used to package solid beverages and seasoning packets (dissolve upon contact with water, avoiding contamination from unpacking), or as biodegradable cling films (need to be composited with starch to improve degradability).

　　Pharmaceutical Carriers:

　　Sustained Drug Release: PVA hydrogels (e.g., crosslinked with sodium alginate) serve as carriers for oral or topical drugs, achieving long-term release by controlling the degradation rate.

　　Surgical Materials:

　　Lubricants for ophthalmic surgery (PVA solution simulates tears, relieving dry eye syndrome).

　　Biodegradable sutures (low alcoholysis degree PVA is woven and implanted into the body, gradually hydrolyzing and being absorbed).

　　Medical films: PVA is blended with polyvinylpyrrolidone (PVP) to prepare swellable hemostatic films for wound care.

　　(3) Construction and Coatings

　　Adhesives:

　　107 glue (condensation product of PVA and formaldehyde) was once used for wall scraping, but is gradually being phased out due to formaldehyde emission issues; now, aldehyde-free PVA adhesives (such as tile adhesive, wallpaper adhesive) are mostly used.

　　Coating Film Formers:

　　Copolymerized with acrylates to prepare interior wall coatings (scrub-resistant, water-resistant), or used as cement additives (improving water retention and adhesion of mortar).

　　Waterproofing Materials:

　　PVA is composited with cement to form a waterproof coating, which forms a tough film layer after curing, preventing water penetration.

　　(4) Daily Chemicals and Environmental Protection

　　Detergent Additives:

　　Added to laundry powder as anti-redeposition agents to prevent dirt from re-adhering to clothes (hydroxyl groups adsorb dirt particles).

　　Environmental Materials:

　　Biodegradable water-soluble films used for pesticide packaging (reducing white pollution), or as water-soluble garbage bags (dissolve in water, suitable for medical waste disposal).

　　Paper Industry:

　　Used as paper surface sizing agents to improve water resistance and printability; or as pulp binders for specialty papers (such as sandpaper, label paper).

　　(5) Other Uses

　　Agriculture:

　　Used as seed coating materials (PVA film wraps seeds, dissolves upon contact with water after sowing, while releasing fertilizer).

　　Preparation of water-retaining agents (copolymerized with acrylates) for agricultural irrigation in arid areas.

　　3D Printing:

　　Water-soluble PVA serves as a support material, which is dissolved and removed with water after printing is completed, suitable for complex structural models (such as hollow parts).