ENCOR® 137 is a vinyl acetate – ethylene latex stabilized with polyvinyl alcohol. The binder is suitable for use in tape joint compounds, cement admixtures as well as the production of redispersible powders.
- Excellent compatibility and stability
- Easy to formulate; offers high efficiency
- Does not require external plasticizer
- Excellent tape bond adhesion and crack resistance
|Total solids, % by weight||56|
|Weight per gallon, lb||8.9|
|Viscosity, Brookfield, cP, #2 LVT @ 30 rpm, 25°C||200|
|Glass transition temperature (Tg), midpoint, °C||18|
|Minimum film-forming temperature (MFFT), °C||5|
1The data provided for these properties are typical values, intended only as guides, and should not be construed as sales specifications.
Joint finishing products are an integral part of gypsum board systems. Their role is to finish the joint between the individual sheets of gypsum board in such a manner that even under critical lighting the whole wall (or ceiling) gives the impression of a monolithic surface.
Figure 1, illustrates the use of joint compound to finish interior walls and ceilings.
Figure 2, illustrates the superior low temperature tape bond adhesion performance of joint compounds formulated with ENCOR®137 latex.
Figure 3. Fiber Tear testing illustrates the excellent durability of joint compounds based on ENCOR®137 latex.
Figure 4, illustrates the superior mud crack resistance of formulations utilizing ENCOR®137. This allows for thicker applications of joint compound to address major irregularities in walls and ceilings.
- HEC and HEMC thickeners are preferred, high molecular weight products are more efficient than lower molecular weight grades.
- ASE and HASE thickener types such as RheotechTM 46, AcrysolTM ASE 60, RheotechTM 4200 and AcrysolTM TT-615 may also be employed.
- HEUR thickener types should be avoided because of undesirable flow characteristics.
Calcium Carbonate Grade
- Primary filler pigment.
- Performance differences can be anticipated with different sources of ground calcium carbonates due to natural variations in quality of calcium carbonate source. Trace minerals and salts in the ground calcium carbonate can negatively impact performance. Any new grade of calcium carbonate should be tested for suitability.
- Calcium carbonate with an average particle size of 6-10 μm is preferred when formulating joint compounds.
Mica and Hydrous Clay
- May be utilized as a particle replacement for Calcium Carbonate to minimize cracking.
- Will impact hardness and porosity of finish.
Perlite and Glass Microspheres
- Utilized in light weight and ultra-light weight formulations.
- Functions as partial replacement for Calcium Carbonate, should be substituted on an equal volume basis taking into account their ultra low density.
- Biocides and mildewcides are necessary to achieve the desired product shelf-life and maximum performance.
- Kathon LX is the recommended package biocide.
- There are several recommended mildewcides and either Polyphase® 663 or Busan 1192D are good choices.
|Weight solids, %||70|
|Volume solids, %||47|
|Weight solids, %||53|
|Volume solids, %||26|