I have read that you cannot store polymer clay in certain plastic containers as it leaches some of the binding chemicals. Is it okay to store the clay in the bottles that prescription medicines come in as I save them to store beads, etc in? Thank you for your wonderful site and jewelry making components.
Polymer clay can usually be stored safely without leaching or bonding to containers with the recycling symbols 2, 4, or 5. Most medicine bottles are classified with the recycling #5 so you should be good to go.
As a reference, the classifications behind the numbers are as follows:
2 = High Density Polyethylene (HDPE) Examples include milk, juice and water bottles.
4 = Low Density Polyethylene (LDPE) Examples include bread bags, plastic grocery bags and squeezable bottles like those for mustard.
5 = Polypropylene (PP): Examples include ketchup bottles, yogurt containers and margarine tubs.
Containers with the #6 as the recycling symbol tend to react to the plasticizer in polymer clay and they do tend to form a bond between each other. This reaction will ruin your clay as well as your storage container.
Uncured polymer does not need to be stored in an air-tight container as nothing is lost from the material while it lays dormant. It should be kept covered so it remains dust free and separated from other colors of polymer or even cured polymer as they will begin to bond together.
When storing canes and designs I haven't completed yet, I use plastic wrap as my cover of choice and then store the canes in a flat filing cabinet. Other designers wrap their canes and then store them on metal baking trays.
- Tammy Honaman, Author, Jewelry-Making Expert and Educator