Sioux Rubber & Urethane Blog

What Rubber is the Best for Mold Making?

Posted by Sioux Rubber & Urethane Team on Jul 27, 2023 10:45:00 AM

When it comes to creating molds, selecting the appropriate type of rubber is crucial for achieving precise and durable results. When selecting the best rubber for mold making, it is vital to consider factors such as the desired level of flexibility, mold complexity, temperature resistance, and compatibility with the materials being molded. Here are some key factors to consider when selecting the best rubber for mold making:


One of the most critical aspects of mold making is accuracy. The rubber used for mold making must be able to reproduce even the smallest details of the original pattern or part. Silicone rubber is often the preferred choice because it can capture intricate details and is known for its ability to create precise and accurate molds. In addition, urethane rubber is highly suitable for mold making due to its exceptional accuracy, as it has minimal shrinkage during the curing process and can capture even the most intricate details, ensuring precise replication of the original object.


Mold-making rubber must also be durable enough to withstand repeated use. Urethane rubber is a popular option for mold making because of its excellent durability, flexibility, and resistance to abrasion. It can withstand multiple pours of various materials without breaking down, making it ideal for high-volume production applications.

Temperature Resistance

Temperature resistance is another critical factor when choosing rubber for mold making. The rubber used must be able to withstand the temperatures used in the molding process without melting or degrading. Silicone rubber has excellent heat resistance and can withstand temperatures of up to 450°F, making it a popular choice for high-temperature applications.

Urethane rubber's exceptional heat resistance makes it an excellent choice for molding applications, ensuring that it can withstand high temperatures without compromising the integrity of the mold or the molded objects.

Chemical Resistance

Depending on the materials used in the casting process, the rubber chosen to create molds must also have excellent chemical resistance. Urethane rubber is resistant to many chemicals, making it an excellent choice for casting applications that require exposure to harsh chemicals.

Choosing the right rubber for mold making is crucial to ensure accurate and long-lasting results. Contact us today to learn more about our custom polyurethane rubber products and to request your quote!

Topics: Rubber Products, Sioux Rubber & Urethane, Custom Rubber Products