8/11/2019 Formulation 004

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 Adhesives and Sealants Starting Point Formulation 

Waterborne, PVAc Wallboard Adhesive

TYPICAL FORMULATION INGREDIENTS AND PROPERTIES

Ingredient Parts by weight

Polyvinyl acetate emulsion 43.67

Modified cellulose thickener 0.30Defoarmer 0.03Benzoic ester plasticizer 10.50

 Alkylphenol ethylene oxide condensate surfactant 0.35 Aromatic sulfuric acid sodium salt dispersant 0.07

Ethylene glycol stabilizer 0.70Inorganic polyphosphate dispersant 0.35Preservative 0.03Calcium carbonate (3-6 micron diameter) filler 23.00

Calcium carbonate (14-21 micron diameter) filler 20.00(US Patent 6,300,400)

Properties

Solids content, % 77-79

Density, lb/gal 12.2

Viscosity, cps 60,000-70,000

Open time, mins 5-10

Shear strength, lb, to gypsum after drying:

• 10 min  2.5-12

• 15 min  5-15

• 20 min  11-12.5

• 40 min  32-35

Applicable Type Waterborne Adhesives

Applicable Base Polymer Polyvinyl acetate emulsions & derivatives (PVAc...)

Applicable Industrial Sectors Buildings & constructions

8/11/2019 Formulation 004

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 Adhesives and Sealants Starting Point Formulation 

PROCESSING

Vinyl acetate emulsion polymers and their additives can be compounded via simple mixing processes. Foroptimum processing the following should be followed:

1. Add VAE emuls ion to mixer.2. Mix in plasticizer and other liquids until a homogenous mixture is obtained.3. Add remaining ingredients.4. Add water to adjus t viscos ity as desired.

APPLICABLE BASE POLYMER PROPERTIES

Waterborne vinyl acetate adhesives for construction applications have relatively good flexibility and lowtemperature properties (by virtue of added plasticizers) and excellent adhesion to wood and paper. Theseadhesives provide a low to medium performance relatively inexpensive adhesive that dries quickly. A typical

formulation consists of VAE latex, filler (if greater viscosity is desired), plasticizer (for improved flexibility), andwater.

RESULTING PROPERTIES

This adhes ive formulation has improved wet tack in which the adhesive joint remains firm immediately after thebond has been es tablished. This adhesive formulation tends to have thixotropic properties that eliminatestringiness and provide good consistency. The adhesive also provides high solids content to lower cost andfaster drying times.

The adhes ive can have an open time greater than about 5 mins and a green strength sufficient to support a 4 footby 8 foot wallboard on a wall frame without fasteners within 15 mins of applying the adhes ive to the wallboardand wall frame.

TIPS & TRICKS

Emuls ion vinyl acetate adhesives can be difficult to apply due primarily to their low sol ids content and foamingcharacteristics. Often fillers and antifoaming agents are employed to solve this problem. With emulsionadhesives, the water carrier provides excellent penetration into porous substrates. Penetration can be controlledby the concentration of particulate additives