Properties/Applications

POLYBOND

Universal PVA

Description

Polybond Universal is a medium viscosity homopolymer emulsion of Vinyl Acetate. The emulsion is stabilised with polyvinyl alcohol and is plasticised with 10% (on polymer solids), of a dibenzoate blend.

Properties/Applications

Polybond Universal has good adhesive properties to a wide range of substrates, such as wood, concrete, paper etc. It has pseudoplastic flow characteristics and good storage stability. Undiluted, it passes the requirements of the bond strength test contained in British Standard 5270:Part 1:1989.

Suitable application areas include :

• Universal Bonding Agent.
• Concrete Additive.
• Sealer.
• Plaster Additive.
• Rendering and Screeding.
• General Woodwork Adhesive.
• Class B Tile Adhesives.

Physical Data

Plasticiser / Dibenzoate Blend
% Plasticiser (on polymer) / 10%
Total Solids / 45 +/- 1%
pH / 4.0 to 6.0
pH Stability / 2.0 to 10.0
Particle Size Range / 0.5 to 1.5 µ approx
Free Monomer Content / Less than 0.5%
Specific Gravity @ 25°C Typical Value / 1.06
Freeze Thaw Stability / Poor
Borax Compatibility / Unstable
Minimum Film Forming Temperature / 2°C to 6°C
Viscosity @ 25°C Brookfield RVT Spindle 5 at 20 rpm / 90 - 110 poise

Evaluation Results Summary

Standard : / BS 5272:Part 1:1989 Bonding Agents for use with gypsum plaster and cement.
Part 1. Specification for Polyvinyl acetate (PVAC) emulsion bonding agents for indoor use with gypsum building plasters.

Product Reference : Polybond - ten random samples from production runs.

Results Summary

Section / Specification / Polybond
2. Composition / Vinyl Acetate Homopolymer / Complies
3. Solids Content / 45 +/- 1%
4. Saponification Value / 575 to 652 mg KOH/g / 626 mg KOH/g
5. Acid Value / <=10mg KOH / 3.2 mg KOH
6. Ash Residue / <=2% by mass / 0.74%
7. Low Temp. Film Formulation / Continuous Film @ 2°C / Complies
8. Bond Strength / <=230kN/m² / 355kN/m²

Comments

Polybond complies with all tested sections of BS 5270:Part1@1989.

NOTES

In order to comply with section 3 of BS5270:Part 1:1989, the manufacturer should establish and quote the preferred dilutions of the product which will produce the following minimum dry coating masses when applied to the surface shown :

• 60 g/m² Bonding coat on a low suction surface
• 40 g/m² Bonding coat on a moderate suction surface
• 15 g/m² Sealing coat on a high suction surface, followed by ;
• 40 g/m² Bonding coat on a sealed high suction surface.

Reference to VS 5492 should be made for definitions and examples of surfaces of different degrees of suction.

For guidance, the following dilutions have been established for Polybond

Low Porosity Substrate / Neat / Undiluted application
Medium Porosity Substrate / 2.5 parts Polybond : 2 parts water
High Porosity Substrate / 1 part Polybond : 2.5 parts water
Product Reference No: PVA / Amendment date August 2002

Stronger than Strength Itself