Comparison of Different Types of Polysilazanes (PHPS, OPSZ, MPSZ) Part Two

• Hardness: PHPS is the highest (up to 9H); OPSZ is medium (5-7H); MPSZ is high (8-9H, similar to high-end OPSZ products).

• Hydrophobicity: PHPS is hydrophilic (SiO₂ surface after conversion); OPSZ is hydrophobic (water contact angle 90-105°); MPSZ is strongly hydrophobic (low surface energy, easy to clean and stain-resistant).

• High Temperature Resistance: PHPS is excellent (>1000°C with no significant weight loss); OPSZ is excellent (retains organic groups, can withstand higher oxidation); MPSZ is good (methyl modification improves thermal stability).

• Corrosion Resistance: PHPS is excellent (dense SiO₂ barrier layer); OPSZ is good (hybrid structure provides corrosion resistance); MPSZ is excellent (resistant to chloride media).

• Flexibility/Adhesion: PHPS is poor (prone to cracking); OPSZ is excellent (organic chain segments provide flexibility); MPSZ is good (balances hardness and flexibility).

• Barrier Properties (Water/Oxygen): PHPS is excellent (low permeability); OPSZ/MPSZ are good (assisted by easy-to-clean surface). • Reactivity: PHPS is high (sensitive to moisture); OPSZ/MPSZ are medium (more stable, easier to store). PHPS coatings are harder and denser, suitable for applications requiring purely inorganic barriers; OPSZ/MPSZ, with the introduction of organic groups, significantly improve hydrophobicity and ease of cleaning, suitable for outdoor or anti-fouling environments.

PHPS Main Applications:

Semiconductor insulation layers, gas barrier coatings, protective coatings. Typical examples include electronic packaging, flexible barrier films, and metal anti-corrosion SiO₂ coatings.

OPSZ Main Applications:

High-temperature resistant coatings, anti-corrosion coatings, easy-to-clean coatings. Typical examples include automotive/building exteriors, metal anti-corrosion, and composite material reinforcement.

MPSZ Main Applications:

Ultra-hard easy-to-clean coatings, scratch-resistant surfaces, ceramic precursors. Typical examples include mobile phone screen protectors, non-stick cookware coatings, and wear-resistant ceramic substrates. PHPS is primarily used in high-purity inorganic conversion applications, such as microelectronics; OPSZ/MPSZ are more geared towards industrial protection and consumer goods, such as anti-fingerprint coatings or high-temperature exhaust pipe protection.

Summary of Advantages and Disadvantages and Selection Recommendations:

• PHPS: Advantages include pure conversion, high hardness, and excellent barrier properties; disadvantages include high reactivity, difficulty in storage, and brittle coatings.

• OPSZ: Advantages include balanced performance, ease of processing, and hydrophobicity and stain resistance; disadvantages include carbon content in the conversion process and slightly lower purity.

• MPSZ: Advantages include outstanding hydrophobicity and ease of cleaning, and high hardness; disadvantages include higher cost, and specific modifications require customization.

In practical selection:

• If pure SiO₂ barrier properties and high hardness are required, prioritize PHPS.

• If hydrophobicity, ease of cleaning, and flexibility are needed, choose OPSZ or MPSZ.