Silicone adhesives fill small but important niches in the pressure sensitive adhesive (PSA) market. They are generally selected for the most demanding industrial applications because of their inherent resistance to temperature extremes, moisture, chemicals, and biological attack. Silicone adhesives also offer excellent dielectric properties so that they are often used as pressure sensitive tapes for the electrical / electronics industry.
Silicone polymers have an inorganic backbone and side groups that are organic. These adhesives are expensive relative to other types of PSAs, and this is the main reason why they are used only in niche markets. Although silicone PSAs provide premium performance, they generally require special formulation, as do other PSAs, to be accurately matched to specific application requirements.
Silicone formulations have the highest temperature and chemical resistance by far, but they are expensive and provide less aggressive bonds than do acrylics or rubber-based adhesives. Silicone PSAs generally demonstrate lower tack and peel strength than other adhesive systems.
However, they provide outstanding temperature and chemical resistance due to their inorganic nature. They have very low glass transition temperatures and, therefore, can be utilized at service temperatures between -73 and 250°C without becoming brittle or drying out. Because of their relatively low surface energy, about 21 mJ/m2, silicone PSAs will bond well to both high- and low-energy surfaces, including etched polytetrafluoroethylene and unetched polyolefins, polyester, and fluorohalocarbon films. Silicone PSAs are the only adhesive that will consistently bond to silicone substrates, so they are often used as a pressure sensitive adhesive on extruded silicone rubber gasketing.
Silicone polymers have an inorganic backbone and side groups that are organic. These adhesives are expensive relative to other types of PSAs, and this is the main reason why they are used only in niche markets. Although silicone PSAs provide premium performance, they generally require special formulation, as do other PSAs, to be accurately matched to specific application requirements.
Silicone formulations have the highest temperature and chemical resistance by far, but they are expensive and provide less aggressive bonds than do acrylics or rubber-based adhesives. Silicone PSAs generally demonstrate lower tack and peel strength than other adhesive systems.
However, they provide outstanding temperature and chemical resistance due to their inorganic nature. They have very low glass transition temperatures and, therefore, can be utilized at service temperatures between -73 and 250°C without becoming brittle or drying out. Because of their relatively low surface energy, about 21 mJ/m2, silicone PSAs will bond well to both high- and low-energy surfaces, including etched polytetrafluoroethylene and unetched polyolefins, polyester, and fluorohalocarbon films. Silicone PSAs are the only adhesive that will consistently bond to silicone substrates, so they are often used as a pressure sensitive adhesive on extruded silicone rubber gasketing.