Polymer foams are mainly divided into two categories: closed-cell foam materials and open-cell foam materials. The soft foam material with open cells has very good compression resilience, and the air flows easily in the cells after compression, so the material can rebound to its original thickness. Foamed materials with closed cells have very low water absorption and are mainly used for insulation, energy absorption and sealing. Common foam names: Polystyrene (PS - closed cell) Polyurethane (PU - closed cell; PU - open cell) Polypropylene (PP - closed cell) Polyethylene terephthalate (PET - closed cell) ) Polyvinyl chloride (PVC-closed cell; PVC-open cell) Polyethylene (PE-closed cell)
If the polymer is insoluble in water, it is difficult to generate shock foam by adding other surfactants. If the monomer is polymerized, it can be considered to add some anionic and cationic surfactants such as cationic quaternary ammonium salts or anionic fatty acid sodium salts during emulsification to form It is in the form of water-based emulsion, but considering the storage stability, it is generally not recommended to use surfactants with strong foaming power. For example, dodecyl dimethyl benzyl ammonium chloride, sodium vinyl sulfonate or alkyl phenol polyoxyethylene ether and other surface activities can generate a large amount of foam, which needs to be targeted according to the chemical properties of your polymer. If not, it will cause flocculation and sedimentation.