Different storage conditions can significantly affect the properties of cured products of polysilazane, mainly manifested as the following differences:
1. The impact of high temperature storage on solidified products
Crosslinking degree and structural changes: High temperature accelerates molecular motion, which may lead to partial pre crosslinking of polysilazane during storage, forming a denser network structure. For example, some polysilazanes may undergo early condensation reactions of silicon nitrogen bonds at high temperatures (such as>40 ℃), resulting in excessively high crosslinking density of the cured product.
Performance performance:
Brittle increase: Excessive cross-linking will reduce the flexibility of the material, making the cured product more brittle and reducing its impact resistance.
Decreased thermal stability: Pre crosslinking may consume some active groups, leading to a decrease in ceramic yield during subsequent high-temperature cracking (such as from normal 60% to below 50%), or the formation of more defective structures.
Uneven mechanical strength: Local pre crosslinking may lead to uneven distribution of mechanical properties of cured products, affecting the reliability of actual use.
2. The impact of high humidity storage on solidified products
Hydrolysis reaction and structural defects:
Moisture sensitive polysilazanes (such as systems containing hydrolyzable silicon nitrogen bonds) are prone to hydrolysis reactions in high humidity environments, generating silanol groups (- Si-OH), which then condense to form silicon oxygen bonds (- Si-O-Si -). This process may disrupt the original molecular chain structure and introduce polar groups such as hydroxyl groups.
Performance performance:
Reduced corrosion resistance: The introduction of hydroxyl groups increases the hydrophilicity of the material, which may make the coating more prone to moisture absorption in humid environments, reducing its salt spray corrosion resistance.
Deterioration of ceramicization quality: Hydrolyzed products may generate more SiO ₂ phase during high-temperature cracking, rather than the target SiCN or SiCNO ceramics, affecting their high-temperature resistance and oxidation resistance.
Reduced adhesion: Hydrolysis reaction may weaken the chemical bond between polysilazane and substrate, leading to easy coating detachment.
3. The effect of light storage on cured products
Photoinduced crosslinking reaction:
Polysilazane containing unsaturated groups (such as vinyl) may undergo free radical polymerization or photooxidation reactions under light (especially ultraviolet), leading to premature crosslinking. For example, some polysilazane can produce local gel within several hours under light.
Performance performance:
Uneven curing: Excessive cross-linking in illuminated areas and insufficient curing in non illuminated areas result in significant local differences in material hardness, wear resistance, and other properties.
Yellowing and accelerated aging: The photo oxidation reaction may cause the material to turn yellow, and even form aging products such as carbonyl groups, shortening its service life.
Decreased dielectric performance: Uneven cross-linking or oxidation products may damage the insulation of materials, especially affecting applications in electronic packaging and other fields.
4. The influence of container material and sealing performance
Impurity introduction and catalytic effect:
Metal containers (such as iron and copper) may release metal ions, catalyzing the hydrolysis or cross-linking reaction of polysilazane, leading to an accelerated solidification rate during storage. For example, iron ions may promote the breaking and recombination of silicon nitrogen bonds.
Performance performance:
Out of control curing: metal ion catalysis may cause polysilazane to quickly gel in storage, lose liquidity and cannot be used normally.
Changes in product composition: Impurities may participate in the curing reaction, introduce unexpected elements (such as iron), and affect the purity and properties of ceramic products.
The consequences of poor sealing: Air or moisture entering the container may cause oxidation or hydrolysis, leading to structural defects in the product, such as increased porosity and reduced coating density.

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