Polysilazane coatings are usually hydrophobic. This is mainly caused by the following factors:
Low surface energy: In the molecular structure of polysilazane, silicon atoms and nitrogen atoms alternate to form the basic skeleton, and the side chain groups are usually organic groups such as methyl and ethyl. These organic groups have low surface energy, which makes the contact angle of water on the coating surface larger and difficult to spread, thus exhibiting hydrophobicity. For example, coatings based on organic polysilazane typically have a water contact angle in the range of 95 ° -105 °.
Tight molecular structure: Polysilazane forms a relatively tight three-dimensional network structure during the curing process. This structure is relatively dense, reducing the pores and channels that water molecules can enter, making it difficult for water to penetrate into the interior of the coating, further enhancing its hydrophobicity.
However, through some special modification methods or processing techniques, the polysilazane coating can also be made hydrophilic. For example, the organic-inorganic hybrid coating formed by using polysilazane or the active Si-N and/or Si-H groups in the SiON coating react with active functional groups such as hydroxyl and carboxyl groups to graft hydrophilic molecules onto the surface of the transition layer, thereby forming a composite coating with polysilazane coating as the bonding layer and hydrophilic layer on the surface.

Room termperature curing polysilazane, pls check IOTA 9150, IOTA 9150K.          
High termperature curing polysilazane, pls check IOTA 9108, IOTA 9118.