Flexible Silicone Sealant Formulation

Designed for both indoor and outdoor applications, this sealant offers long-lasting flexibility and watertight seals for bathrooms, windows, and roofing joints. With excellent resistance to UV radiation and weathering, it consistently performs even in harsh climates.

Technical Specifications

  • pH Level: N/A
  • Shelf Life: 24 months when stored in original, sealed containers at 5°C to 25°C
  • Batch Size: 500 kg
  • Processing Time: 2 hours including mixing and quality control
  • Temperature: 25°C throughout main mixing and final processing phases
  • Storage: Store in a cool, dry place away from direct sunlight and moisture
  • Viscosity: 150,000 – 250,000 cP
  • Certification: ASTM C920 for elastomeric joint sealants, ISO 9001 for quality management

Ingredients

IngredientPercentageFunction
Polydimethylsiloxane56.0%Primary silicone base providing flexibility and seal integrity
Silicone Dioxide17.0%Reinforcing filler to enhance mechanical strength
Vinyltrimethoxysilane3.0%Crosslinker for curing and structural network formation
Calcium Carbonate20.0%Filler to improve rigidity and reduce cost
Tin Catalyst0.5%Catalyst to accelerate the curing process
UV Absorber1.0%Reduces degradation due to UV exposure
Pigment2.5%Provides desired color and opacity

Manufacturing Process

Pre-Mixing Phase

  1. Pre-weigh all raw materials based on batch size and ensure equipment is clean.
  2. Mix Silicone Dioxide and Calcium Carbonate in a planetary mixer at room temperature for 15 minutes to evenly distribute the fillers.

Main Mixing Phase

  1. Add Polydimethylsiloxane into the mixer containing fillers slowly, maintaining a temperature of 25°C.
  2. Continue mixing at 100 RPM to achieve a homogeneous mixture over 30 minutes.
  3. Incorporate Vinyltrimethoxysilane and Tin Catalyst gradually, ensuring thorough dispersion.

Final Processing Phase

  1. Introduce UV Absorber and Pigment into the batch, mixing for an additional 20 minutes.
  2. Check viscosity (150,000 – 250,000 cP) using a Brookfield viscometer and adjust formulation if necessary.
  3. Perform quality control to ensure no air entrainment and confirm consistency.

Usage Instructions

Apply using a caulking gun onto clean, dry surfaces. Smooth the bead with a spatula or finger within 10 minutes of application. Allow 24 hours for full cure.

View full formulation details on AIFormulator