Condensation-type room temperature vulcanized AB silicone rubber for artificial stone mold replication

Condensation-type room temperature vulcanized AB silicone rubber for artificial stone mold replication. For inquiries, contact Ms. Chen at 13662816580 (same number for WeChat).

Condensation-type room temperature vulcanized AB silicone rubber mold making
This step is the core, requiring the replication of prototype details using condensation-type room temperature vulcanized AB silicone rubber to obtain a reusable flexible mold.

Material selection:
Hardness: Choose based on the complexity of the prototype. For complex details (such as deep grooves, fine patterns), select soft silicone rubber with a Shore A hardness of 20-30 (good demolding performance); for simple shapes, choose hard silicone rubber with a Shore A hardness of 40-60 (longer mold life, capable of 50-100 replications).
Type: Prioritize room temperature vulcanized silicone rubber (RTV-2), which requires no heating equipment and is simple to operate; for mass production, heat-vulcanized type (HTV) can be selected, offering fast vulcanization (100°C × 30 minutes).
Key parameters: Tear strength ≥25 kN/m (to reduce tearing during demolding), elongation ≥300% (to improve flexibility during demolding).

Silicone rubber preparation:
Mixing in proportion: Condensation-type room temperature vulcanized AB silicone rubber typically consists of two components: A (base rubber) and B (curing agent). They must be mixed strictly according to the instructions (common weight ratios are 10:1 or 5:1), using an electronic scale (error ≤ ±1%) to avoid incomplete curing or excessive brittleness.
Stirring and degassing: For manual stirring, stir clockwise along the container wall for 3-5 minutes (to avoid trapping air), or use an electric stirrer (speed 300-500 rpm); after mixing, pour into a vacuum degassing machine (vacuum degree -0.1 MPa) and degas for 5-10 minutes until no bubbles escape (bubbles can cause pinholes on the mold surface).

Pouring and vulcanization:
Pouring: Slowly pour the degassed silicone rubber around the prototype (it is recommended to use a surrounding board to secure the prototype and create a pouring space). The height should cover the highest point of the prototype by 5-10 mm; if the prototype has deep holes/grooves, first inject a small amount of silicone rubber and use a brush to coat the detailed areas to avoid trapping bubbles.
Vulcanization: Room temperature vulcanization (25°C): Let it sit for 6-24 hours (specific time depends on the material, harder materials require longer), avoiding vibrations during this period;
Heat vulcanization: If acceleration is needed, heat in an oven at 60-80°C for 2-4 hours (excessive temperature can cause silicone rubber aging).

Demolding and trimming:
After vulcanization is complete, slowly peel the silicone rubber mold from the edges of the prototype (soft silicone rubber can be directly folded for demolding, while hard silicone rubber requires gently prying the edges with tools), avoiding forceful pulling that could tear the mold;
Trimming the mold: Use scissors or a blade to remove burrs and flashes from the mold edges, and check if the details are intact (if there are bubble defects, they can be repaired with silicone rubber).

Choose a factory-guaranteed condensation-type room temperature vulcanized AB silicone rubber. For inquiries, contact Ms. Chen at 13662816580 (same number for WeChat).