DOWSIL 732 Multi-Purpose Sealant, 1K silicone sealant and adhesive

Brief description

DOWSIL 732 is a single-component silicone sealant and adhesive (RTV) for universal sealing and bonding in industrial environments. The material is stable (does not run), is easy to apply, and cures at room temperature through air humidity to form a tough, permanently elastic rubber. Available in white and transparent (clear to translucent).

Your advantages with DOWSIL 732

• 1K, ready to use: no mixing, no pot life, direct application
• Non-running: ideal for vertical joints and gaps
• Fast skin formation: Skin Over typically approx. 7 minutes, Tack Free typically approx. 20 minutes
• Permanently elastic and robust: hardens to form a tough, flexible rubber
• Wide temperature range: stable and flexible from minus 60 °C to plus 180 °C, briefly up to plus 205 °C
• Good electrical insulation: excellent dielectric properties
• Standards and compliance: Complies with MIL A 46106 and requirements according to FDA 21 CFR 177.2600 (Rubber articles intended for repeated use), among others.

White or transparent: which version is right for you?

White

• If the joint is visible and should look clean
• Typical for housings, covers, apparatus construction, light-colored substrates

Transparent (clear to translucent)

• If the joint should remain as inconspicuous as possible
• Typical for glass, visible surfaces, transparent covers

Typical applications

DOWSIL 732 is suitable for general industrial sealing and bonding, for example:

• Sealing housings, covers, and feedthroughs against moisture and dust
• Elastic bonding, fixing, and joint sealing in the MRO environment
• Applications where sealing and electrical insulation are required at the same time

Key technical data (typical values)

• Consistency: stable paste, non-sagging
• Extrusion rate: typically 350 g/min
• Skin Over: typically 7 min
• Tack Free: typically 20 min
• Density: typically 1.04
• Hardness: typically Shore A 25
• Tensile strength: typically 2.3 MPa
• Elongation at break: typically 540%
• Curing: approx. 3 mm in 24 hours at room temperature and 50% RH

Processing instructions (to ensure reliable adhesion)

1. Prepare the surface: Clean and dry the surface, degrease it, and remove any contaminating residues. Suitable solvents include isopropanol, acetone, or MEK.
2. Application and joining: Apply material to a surface, then join promptly.
3. Smoothing: Complete tool machining before skin formation.
4. Allow to harden: Hardening proceeds from the outside in; deep cross-sections require correspondingly more time.
5. Optimize adhesion: Unprimed adhesion is possible on many substrates. For maximum adhesion, Dow recommends DOWSIL 1200 OS Primer.

Notes on material compatibility

• DOWSIL 732 is acetoxy-curing. By-products are formed during curing (typically acetic acid odor). For corrosion-sensitive metals and in closed volumes, check suitability in the specific application.
• Good adhesion is possible on many substrates; PTFE, PE, PP, and related materials are typically critical.