I. Introduction to Ultra-Low Molecular Weight Polyvinyl Alcohol (PVA)
Ultra-low molecular weight polyvinyl alcohol resin (PVA) appears as white or slightly yellow flakes; it is non-toxic, odorless, and pollution-free, and dissolves in water at 60–80℃. Its aqueous solution exhibits good adhesion, film-forming properties, and emulsifying properties.
The formed film possesses excellent adhesion, solvent resistance, abrasion resistance, tensile strength, and oxygen barrier properties. Because polyvinyl alcohol possesses both hydrophilic and hydrophobic functional groups, it exhibits interfacial activity and can be used as a protective colloid in polymer emulsification and suspension polymerization reactions. It also possesses chemical properties such as esterification, etherification, and acetalization of long-chain polyols.
Main Features:
Film-forming properties: This PVA easily forms films, resulting in films with excellent mechanical properties.
Protective colloid: Acts as a protective colloid in suspension polymerization reactions.
Emulsifying properties: Can be used as a polymer emulsifier in the chemical industry.
Low molecular weight: This PVA has an ultra-low degree of polymerization, increasing the solid content of the product.
Thermal stability:
The appearance gradually changes when the sheet is heated to approximately 100°C.
Partially alcoholyzed PVA begins to melt at approximately 190°C and decomposes at 200°C.
Completely alcoholyzed PVA begins to melt at approximately 230°C and decomposes at 240°C.
The lower the degree of polymerization, the faster the weight loss; the higher the degree of alcoholyzation, the shorter the decomposition time.
II. Performance Indicators of Ultra-Low Molecular Weight Polyvinyl Alcohol PVA
| Viscosity (mPa·s) | Degree of alcoholysis | Volatile matter (%) | Ash content (%) | pH value | Degree of polymerization | Molecular weight |
|---|---|---|---|---|---|---|
| 2.0–3.0 | 86.0–90.0 | ≤7.0 | ≤0.5 | 5–7 | 300–400 | 8000–12000 |
III. Main Applications of Ultra-Low Molecular Weight Polyvinyl Alcohol PVA
This PVA can be widely used in multiple industries:
Chemical Industry: As a polymerization emulsifier, dispersant, and protective colloid for polymer polymerization.
Textile Industry: Warp sizing agent, weaving agent... Finishing agents, vinylon fiber raw materials
Paper industry: Paper adhesives, sandpaper
Production of polyvinyl alcohol formaldehyde, acetal, and butyral resins
Agriculture: Soil conditioners, pesticide adhesion enhancers
Polyvinyl alcohol films
Various adhesives
Ceramics, alumina granulation, ferrite magnets
Daily cosmetics
Pharmaceutical excipients
High-frequency quenching agents, etc.
IV. Ultra-Low Molecular Weight Polyvinyl Alcohol (PVA) Usage Method
1. Dissolution Method: Add PVA to room temperature water and stir. After swelling for about 30 minutes, heat and stir continuously for about 1 hour. When the temperature reaches 60℃, maintain a constant temperature until completely dissolved.
Alternatively, add PVA to a container containing water, directly pass high-temperature steam through, and finally adjust to the required concentration to obtain a clear and transparent aqueous solution.
2. Check for Complete Dissolution
Take a small amount of solution and add 1–2 drops of iodine solution:
If blue, granular, transparent clumps appear, it indicates incomplete dissolution.
If the color spreads evenly, it indicates complete dissolution.
3. Adding Defoamer
Foaming may occur when the solution concentration is high or the stirring speed is fast. Defoamer can be added:
0.01–0.05% octanol or tributyl phosphate (based on PVA)
Or 0.2–0.5% silicone emulsion (based on PVA)
V. Packaging and Storage
Packaging Method
Paper-plastic composite bag packaging, lined with a plastic bag. Net weight per bag:
1kg or 20kg / 25kg.
Transportation Requirements
Use clean transportation vehicles during transportation. Protect from moisture, rain, and sunlight. Handle with care to avoid damage.
Storage Conditions
Store in a dry, well-ventilated indoor environment at a temperature of 5–30℃.
Avoid heat sources, moisture, and direct sunlight.
Seal tightly after opening.
Shelf life: 36 months.
Website: www.china-pva.net
Whatsapp: 0086-15380400285
E-mail: sales2@china-pva.net
