Breve introducción:
Polyvinyl Alcohol 20-88 (also known as PVA 2088 or 088-35) is a partially hydrolyzed grade polymer characterized by a unique medium-high viscosity range.
With a viscosity of 28.0 – 43.0 mPa.s, PVA 20-88 offers stronger initial tack and film thickness compared to standard 17-88 grades, while maintaining better flow properties than high-viscosity 24-88 grades. This balance makes it the preferred choice for industrial applications requiring precise rheological control, such as stiffening agents for abrasives and re-wettable adhesives.
Presupuesto:
| Artículo | Especificación |
|---|---|
| Grado de alcoholismo (mol%) | 86.00 - 90.00 |
| Viscosidad (mPa·s) | 28.0 - 43.0 |
| Contenido volátil (wt%, máx.) | 5 |
| Pureza (wt%, mín.) | 93.5 |
| Valor de pH | 5 ~ 7 |
| Contenido de cenizas (wt%, máx.) | 0.5 |
Características principales:
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Solubilidad: Easily soluble in water. While it can dissolve slowly at room temperature, it is recommended to dissolve in hot water above 85°C for efficiency.
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Processing Tip: Foam may be generated during dissolution; adding a defoaming agent is recommended.
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Punto de fusión: As a partially hydrolyzed grade, it begins to melt around 180-190°C and decomposes above 200°C.
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Viscosidad: Exhibits excellent bonding strength not only to hydrophilic materials (cellulose, paper) but also to hydrophobic fibers.
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Propiedades cinematográficas: Forms flexible, tough films with excellent barrier properties against gases.
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Compatibilidad: Compatible with starch, gums, and other emulsions.
Aplicaciones:
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Coated Abrasives & Molds: Specifically used for base fabric stiffening and reinforcement in the abrasives industry (e.g., sandpaper backing).
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Adhesivos: Ideal for formulating re-wettable adhesives (remoistening glues) used in postage stamps, envelopes, and paper tapes.
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Industria textil: Used in fiber processing for short fibers and long filaments to improve weaving efficiency.
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Film Processing: Used as a raw material for manufacturing water-soluble films.
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Stabilizer: Functions as a protective colloid in the polymerization of Vinyl Acetate (PVAc) emulsions.
Embalaje:
- Embalaje: 25 kg por saco.
- AlmacenamientoAlmacenar en un lugar fresco, seco y bien ventilado para evitar que se apelmace y absorba la humedad.
Producto Almacenamiento:
Conservar en un lugar seco y bien ventilado para evitar la absorción de humedad.
Preguntas frecuentes:
Q: When should I choose PVA 20-88 over PVA 17-88?
A: You should choose PVA 20-88 when you need slightly higher viscosity (28-43 mPa.s) and stronger bonding strength than what 17-88 (19-32 mPa.s) can offer. It is ideal for applications where 17-88 is too thin or runny, such as in fabric stiffening or vertical adhesive applications.
Q: Does PVA 20-88 foam during dissolving?
A: Yes, like many partially hydrolyzed grades, it can generate foam during the dissolution process. We recommend adding a small amount of defoaming agent (antifoam) during the heating process to ensure a clear, bubble-free solution.
Q: What is the melting temperature of PVA 20-88?
A: Unlike fully hydrolyzed grades which melt at higher temperatures (~230°C), PVA 20-88 begins to melt at a lower range of 180-190°C. This lower melting point can be advantageous in certain thermoplastic processing applications.
Need Medium-High Viscosity PVA? Solicita un presupuesto. We supply premium Polyvinyl Alcohol 20-88 for specialized industrial applications.
