ENCOR® 167S Latex
ENCOR® 167S latex was developed as a binder for high performance sealants. It’s excellent exterior durability and adhesion enables the formulator to prepare a broad range of ASTM C834 and C920 compliant sealants.
The binder’s low glass transition temperature allows for the formulation of sealants with outstanding low temperature flexibility without the need for external plasticiziers. The elimination of external plasticizer has the added benefit of improved dirt pickup and mildew resistance.
- Excellent exterior durability
- Outstanding adhesion characteristics
- Excellent performance in plasticizer-free formulations
|Total Solids, % by weight||62|
|Weight per Gallon, lb.||9.0|
|Particle Size, microns||0.3|
|Viscosity, 25°C, cP (Brookfield, RVT #6, 60 rpm)||200|
|Minimum Filming Temperature (MFFT), °C||<0|
|Glass Transition Temp. (Tg), midpoint °C||-44|
1Typical values not to be construed as sales specifications.
* These products meet the standards of Arkema Coating Resin's EnVia® program. These products are designed to assist formulators in meeting their sustainability and regulatory goals in their finished products.
External plasticizers have traditionally been used in the formulation of water-based sealants and sealants to improve the lower temperature performance characteristics.
Plasticizer migration can create a host of problems, including:
- Paint discoloration
- Dirt and mildew pickup
Plasticizer migration can result in glossing in paint.
Figure 1, illustrates the impact of plasticizer migration on the gloss level of paint applied over caulk-filled nail holes.
Dirt and mildew pickup related to plasticizer migration are additional concerns that plague professional and DIY painters. By eliminating plasticizer or adjusting P/B ratios, ENCOR® 167S latex allows manufacturers to tailor formulations to their specifc performance and cost requirements.
Figure 2, illustrates the negative impact the use of plasticizer in a conventional caulk formulation can have on dirt pickup and mildew resistance.
Figure 3, illustrates the negative impact of plasticizer on the dirt pickup and mildew resistance of sealants formulated to conform with ASTM C920. The sealants were exposed for 24 months.
Figure 4, illustrates the superior performance of ENCOR® 167S latex relative to other plasticizer-free formulations. The sealants were exposed for 24 months.
Figure 5, illustrates the superior performance of ENCOR® 167S latex relative to externally plasticized formulations. The sealants were exposed for 24 months.
Formulating ASTM C834 compliant sealants
Low temperature flexibility and extension recovery are two performance characteristics.
|ASTM C734||Conventional A |
|Conventional B |
| ENCOR® 167S |
|Low Temp Flex. -18°C
|Recovery Adhesion Loss||
Table 1, illustrates the superior performance delivered by ENCOR® 167S latex when compared to conventionally plasticized sealant binders. ENCOR® 167S latex delivers the required low temperature flexibility and extension recovery even at higher pigment to binder ratios.
Figure 6 - Formulating ASTM C920 compliant sealants
ASTM C719 Cyclic Movement and ASTM C793 Low Temperature Flexibility
Figure 6, illustrates the formulation space for ASTM C920 sealants. With ENCOR® 167S latex, ASTM C920 Class 35 performance can be achieved without the need for external plasticizer at a pigment/binder ratio of 1.2. External plasticizer may be employed with ENCOR® 167S latex to achieve desired performance at higher pigment to binder ratios.
Figure 7, is a comparison of the tensile-elongation performance of a conventional sealant using an external plasticizer (30% based on polymer solids) compared to a plasticizer-free formulation based on ENCOR® 167S latex.
ASTM C794 Adhesion-in-Peel
Figure 8, illustrates the superior peel adhesion of sealants formulated with ENCOR® 167S latex. A sealant with greater than 5 pli adhesion to both aluminum and glass substrates was formulated at a pigment to binder ratio of 1.5 without the need of