In recent years, the demand for sealant in the construction field has been increasing, among which the silicone sealant is widely used and has a large amount. The silicone sealant is prepared with polysiloxane as the main raw material, and its molecular chain is composed of siloxane chain, which is cross-linked to form a network of siloxane chain skeleton structure during the curing process. The bond energy of Si-0 (444 kJ/mol) is very high, which is not only much higher than the main chain bond energy of other ordinary polymers, but also higher than the UV light energy (399 kJ/mol). Therefore, Si-0 has excellent high and low temperature resistance, weather resistance and UV light aging resistance.
5235 special silicone modified polyester resin is a specially treated silicone modified polyester resin with excellent film-forming property, high gloss, high temperature resistance, high hardness baking resin, excellent physical compatibility and excellent storage stability. The hardness reaches 7H after complete curing on stainless steel plate.
1) High hardness and good toughness: the surface hardness of stainless steel substrate can reach 7H after curing and film forming;
2) Good adhesion: it can reach grade 0 on metal substrates such as stainless steel, and some substrates can reach grade 1; 3) High fullness, high gloss, leveling;
4) High transparency: the paint film is colorless and transparent, with light transmittance ≥ 92%; (Various colors can be modulated by yourself)
5) Good heat resistance: varnish resin can withstand 350 ℃ high temperature for a short time;
6) With excellent storage stability, it can grind various high-temperature resistant color pastes
7) Excellent compatibility with any other silicone polyester resin
8) It can be solidified to form film in the temperature range of 180-280 ℃
Application range of resin:
1. Used separately for high-temperature resistant coatings, such as hairpin coating, non-stick pot coating, high-temperature resistant industrial coating, etc
2 Grind various high-temperature resistant color pastes
3. Mix with other resins to improve heat resistance and luster
4. Replacement of general nano-silicone resin
In addition, silicone sealant is also a good adhesive material. Its adhesive performance to glass is very excellent, and it is often used for sealing and bonding of double-layer insulating glass. Reinforcing filler accounts for a relatively high proportion in the formula of silicone sealant, and the commonly used ones include Nanomaterial calcium carbonate, fumed silica, carbon ink, etc. When the nanomaterial calcium carbonate is used as reinforcing filler, the dosage can reach 60% of the total mass of the system. In addition, some silicone sealants will also add incremental fillers to reduce costs, adjust and improve thixotropy and fluidity. The commonly used incremental fillers are heavy calcium carbonate. The common feature of the above fillers is that the density is high, such as the density of Nanomaterial calcium carbonate is 2.7g/cm3, which also leads to the high density of the final product sealant, and the density of most silicone sealant is about 1.5g/cm3. Hollow glass microsphere, also known as hollow glass microsphere, is a lightweight inorganic powder material developed in recent years.
Hollow glass beads are borosilicate glass formed at high temperature (>1400 ℃) and have stable chemical properties. The hollow glass bead is a hollow, thin-walled closed spherical structure with thin gas inside. This special structure makes it have the characteristics of low density, low thermal conductivity and high compressive strength. The true density of hollow glass bead is 0.12-0.70g/cm3, and the thermal conductivity is 0.038-0.085 W/(m · K). It can be used as a semi-reinforcing filler in silicone sealant, effectively reducing the density and thermal conductivity of the sealant, and also improving the thermal deformation temperature of the sealant. In addition, hollow glass beads generally do not react with substrates or other substances, and are suitable for a variety of systems.
