Most synthetic turf problems are caused by seam failures, because buyers and installers unknowingly make poor adhesive choices. Using a "high green strength" adhesive offers a simple solution to seam problems during installation, and durability concerns afterward.
Q. Explain the term "high green strength." And what is the difference between a high green strength adhesive and one with low green strength?
A. A high green strength adhesive has inherently high tack, grab or grip during installation, as opposed to most adhesives with low green strength, which are oily or slippery liquids during application and cure.
A high green strength adhesive helps the installer overcome the troublesome forces of turf movement during installation, particularly outdoors. These forces might include wind lift, edge curl, creep, wrinkling, buoyancy from unexpected rain, and expansion or contraction due to surface temperature changes from desert heat, freezing, sunlight, shadows, passing clouds, etc. Conversely, a low green strength adhesive is slippery and can cause squeeze out, oozing and foaming through seams.
Q. What are some examples?
A One-part liquid urethanes that are solvent-free do not have high green strength. Their isocyanate (NCO) contents above 8% can cause a host of installation problems, ranging from crystallizing (turning solid) at about 50°F and not re-liquifying when warmed, to foaming under the turf and through seams in high humidity, to slow cure in low humidity, to negligible tack, grab and grip during installation, which allows for unwanted turf movement.
Oppositely, many solvent-based, one-part urethane adhesives with low NCO from 3% to 6%, have high green strength, which enables turf installations in any condition. Also, they do not crystallize on cold days, do not foam on humid days, and do not stop curing in dry desert conditions. Unexpected rain shortly after application doesn't hurt them. Hence, installers who use high green strength adhesives get the job done faster.
FOR MORE INFORMATION
Synthetic Surfaces Inc.
908-233-6803
www.nordot.com