Polymer clay

While it was not suitable for use in her factory, Kruse gave some to her daughter Sophie, who was known in the family as "Fifi", who successfully used it as modeling clay.

Plastigels retain their shape even when heat is applied, which is why polymer clay does not melt or droop when oven cured.

Small amounts of zinc oxide, kaolin, or other fillers are sometimes added to increase opacity, elastic modulus, or compression strength.

This involves kneading the clay by hand, passing it between two rollers, or using a low-shear mixer to break up any resin particle adhesions.

[citation needed] Polymer clay safety is the subject of concern specifically regarding the long-term effects of exposure to certain phthalate plasticizers that have been classified as endocrine disruptors.

If the clay does burn because of a mistake or if the oven malfunctions, a small amount of hydrogen chloride gas could be released, which may cause odor and some eye or nose irritation.

[10] Due to the testing requirements and regulations, clay products that would be used to hold or serve food or beverages are not recommended or intended for these applications.

Plasticizers remain in the cured product and can leach out, making it a potential health hazard for both the modeler and end user.