Physical blowing agent class

According to gas generation means, the physical blowing agent and blowing agent can be

divided into two categories chemical foaming agent .
① physical white foaming agent : is generally odorless, non-toxic, inert gas, or a good

stability, low boiling point non-flammable liquid. Common inert gases are nitrogen, carbon

dioxide, and air, low boiling point liquids used tetrachloroethane, methylene chloride, and

pentane. In addition, the dissolution of

Solid compound (such as salt) is also commonly used physical blowing agents. Physical

blowing agents suitable for polystyrene, polyethylene, polypropylene, polyvinyl chloride

foam
② chemical blowing agents: stable at room temperature, and the plastic processing

temperature could explain the large amount of gas of the compound. In the foam

manufacturing applications is very common. The chemical blowing agent used in industry is

the release of most of the nitrogen gas as the main component of an organic compound, and

Can decompose and release ammonia or carbon dioxide, respectively, ammonium bicarbonate and

sodium bicarbonate. Chemical blowing agents suitable for various multi-foamed

thermoplastics. In order to reduce chemical decomposition temperature of the blowing agent,

to improve its dispersion and the amount of foam, often can be activated using one of the

Science foam blowing agent accelerator, or co-blowing agents, such as salicylic acid and

urea.