FAQs
What is SILASTIC RTV-4230-E used for?
It is a two-part, pourable silicone rubber for making flexible, durable molds. After mixing with its curing agent, it can reproduce parts with unusual shapes, severe undercuts, and close tolerances. Its high strength, tear resistance, and low shrinkage make it well suited to detailed, repeatable mold-making work.
Is RTV-4230-E safe for food-contact molds?
The source describes the rubber as acceptable for food contact, which is why it is used for molds such as confectionery and bakery forms. Because formal food-contact compliance can depend on the specific application and jurisdiction, users should confirm suitability and review the Safety Data Sheet for their intended use.
What causes cure inhibition, and how do I avoid it?
Addition-cure silicones like this can be inhibited by sulfur- or organometallic-salt-containing materials, including some organic rubbers and other RTV silicones, and by surfaces previously in contact with them. Dow recommends brushing a small amount of catalyzed rubber on a test area first; gummy or uncured results indicate inhibition.
Why is high tear strength important in a mold rubber?
High tear strength allows a mold to flex and stretch during demolding without tearing, which is important when reproducing intricate shapes with undercuts. Combined with high elongation and tear resistance, it extends mold life over many casting cycles, protecting your investment in complex, detailed molds.
How is the rubber prepared and poured?
The two components are combined and thoroughly mixed to form a pourable liquid, which is then poured over a clean master. Setup rate for thick sections depends on the size and shape of the piece. Consult the technical data sheet for mix ratio and cure details before starting production.
