CVD Deposited Epoxy Copolymers as Protective Coatings for Optical Surfaces

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Engineering

Background:

• Optical surfaces require robust protective coatings to maintain performance.
• Existing coating methods may be costly or lack desired durability.
• Copolymer thin films offer tunable properties for advanced applications.

Purpose of the Study:

• To synthesize and evaluate copolymer thin films for optical surface protection.
• To investigate the chemical durability, corrosion resistance, adhesion, thermal stability, and optical properties of the films.
• To explore the initiated chemical vapor deposition (iCVD) process as a viable fabrication method.

Main Methods:

• Synthesis of copolymer thin films via initiated chemical vapor deposition (iCVD).
• Incorporation of glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA), and 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (V4D4).
• Evaluation of film properties including chemical durability, corrosion resistance, adhesion, thermal resistance, and optical transmittance.

Main Results:

• Crosslinked thin films demonstrated high chemical resistance to organic solvents and excellent substrate adhesion.
• Poly(GMA-co-EGDMA) and poly(GMA-co-V4D4) copolymers provided protection against water and salt exposure with minimal thickness loss.
• Films exhibited high optical transparency (~90% in the visible spectrum).

Conclusions:

• The synthesized copolymer thin films are suitable for protecting optical surfaces.
• The iCVD process offers a fast, low-cost method for fabricating these protective coatings.
• Combining GMA's mechanical properties with V4D4's chemical durability yields high-performance coatings.