What are the differences in shrinkage rates of different types of silicone 3D printing materials?
Common silicone 3D printing materials are mainly divided into addition silicone and condensation silicone according to their chemical types. There are certain differences in their shrinkage rates, as follows:
Addition silicone: The shrinkage rate is generally less than or equal to one thousandth. During the curing process, cross-linking is mainly carried out through silane addition reaction. The reaction is relatively stable and complete, the volume shrinkage is small, and the printing shape and size accuracy can be better maintained. It is suitable for 3D printing products with high precision requirements, such as some precise medical models, electronic device packaging, etc.
Condensation silicone: The shrinkage rate is usually less than or equal to three thousandths. Small molecular byproducts such as ethanol and water will be produced during curing. The volatilization of these byproducts may cause the material to produce a certain volume shrinkage during the curing process. The shrinkage rate is slightly higher than that of addition silicone. It is often used in areas where the precision requirements are not extremely high and cost control is more sensitive, such as some ordinary silicone mold making, simple silicone decorative parts printing, etc.