Polysiloxane type defoamer

Oct 18, 2016

Polysiloxane defoamer with defoamingrapidly, anti-foam for a long time and safe non-toxic and so on. But it isinsoluble in water, high temperature, alkali resistance is poor, polyetherdefoamer high temperature, strong alkali resistance, but its defoaming speedand suppression bubble time are not ideal The polyether chain is grafted intothe polysiloxane chain through the condensation technology, which has theadvantage of the second kind of antifoaming agent, and becomes a defoamingagent with excellent performance and wide application. In the molecule of thesilicon ether copolymer, the siloxane segment is a lipophilic group and thepolyether segment is a hydrophilic group. The poly (ethylene oxide) chains inthe polyether segment provide energy for hydrophilicity and foaming, and thepolyoxypropylene chains provide energy for hydrophobicity and penetration, andhave a strong effect on reducing the surface tension. The group of polyetherend groups also had a strong influence on the properties of the silane ethercopolymer. Common end groups are hydroxyl, alkoxy and so on. By adjusting therelative molecular mass of the siloxane segments in the copolymer, thecopolymer can be made to protrude or weaken the properties of the silicone. Likewise,changing the relative molecular mass of the polyether segment increases ordecreases the proportion of silicone in the molecule and can also affect theproperties of the copolymer. Polyether modified silicone defoamer is easy toemulsify in water, also known as "self-emulsifying defoamer". At itscloud point temperature above the loss of water solubility and mechanicalstability, and acid, alkali and inorganic salts, can be used under harshconditions of defoaming. Widely used in polyester fabric dyeing process, thefermentation process of defoaming.