Siliconized Acrylic Waterborne Sealant
TYPICAL FORMULATION INGREDIENTS AND PROPERTIES
APPLICABLE BASE POLYMER PROPERTIES
Acrylic emulsion based sealants have taken over many of the applications where a higher movement capability is required than for polyvinyl acetate sealants. Acrylic sealants can also be used outdoors, whereas the polyvinyl acetate sealants have inferior exterior durability.
Acrylic emulsion polymers are ideally suited to the formulation of medium performance sealants. There is a significant variation in the types of base polymer emulsions that are available, and these emulsions are easy to formulate. This gives the formulator a wide latitude for compounding to meet specific requirements. Sealants based on acrylic emulsions provide tough, elastic systems, with high adhesion and durability, and they are very environmentally friendly and easy to use.
Organosilanes will provide improvement in both dry and wet adhesion properties of the acrylic sealant. These are used in very small quantities: 0.5 to 0.1% of the total formulation. These water based formulations are sometimes referred to as silconized sealants even though they are far different than the high performance silicone sealants.
Organosilanes form a chemical bridge between the base polymer in the sealant and the substrate. Organosilanes are most efficient on metal, glass, ceramic and other high energy substrates. They provide little if any advantage on low energy substrates.
Siliconized acrylic systems are conventionally found in hardware stores for the consumer markets. The table above provides a formulation for a high quality “siliconized” acrylic sealant.
TIPS & TRICKS