1. Polyurethane foaming agent is the product of cross combination of aerosol technology and polyurethane foam technology. Sponge state appears in the two types: branch pipe type and gun type. Styrofoam, as a foaming agent for microcellular foam plastics production, can generally be divided into physical and chemical types, which are classified according to whether the gas generation is a physical process (i.e. volatilization or sublimation) or a chemical process (i.e. destruction of chemical structure or other chemical reactions).
ii. performance description: in general, the surface drying time is about 1 minutes (at room temperature of 2℃), and the total drying time varies with the ambient temperature and humidity. In general, the total drying time is about 4-6 hours in summer, and it takes 24 hours or more in winter. Under normal use conditions (with a covering layer on its surface), it is estimated that its service life is not less than ten years, and the cured foam maintains good elasticity and adhesion at the temperature range of-1℃ ~ 8℃. The cured foam has the functions of caulking, bonding and sealing. In addition, the flame-retardant polyurethane foaming agent can reach grade B and C flame retardancy.
3. Disadvantages:
1. Polyurethane foam caulking agent, with high temperature, will flow and poor stability. Not as stable as polyurethane rigid foam.
2. Polyurethane foam caulking agent, the foaming speed is too slow to carry out large-scale construction, the flatness can not be controlled, and the foam quality is too poor.
3. Polyurethane foam sealant is expensive.