Methods for recovering expanded polymer tooling
Methods of recovering and/or recycling expanded polymer tooling, the methods including collecting expanded polymer tooling, reducing the collected expanded polymer tooling into smaller particles, treating the reduced expanded polymer tooling in order to yield an at least partially purified recovered polymer composition, and then collecting the at least partially purified recovered polymer composition. The at least partially purified recovered polymer composition can then be used to form new expandable polymer tooling.
1. A method for recycling an expanded polymer composition, comprising:
collecting the expanded polymer composition;
reducing the collected expanded polymer composition into smaller particles;
treating the reduced expanded polymer composition to yield an at least partially purified recovered polymer composition, including:
softening or dissolving the reduced expanded polymer composition with a nonpolar solvent, and
subsequently treating the reduced expanded polymer composition with a polar solvent in order to remove one or more foaming agents from the polymer composition; and
collecting the at least partially purified recovered polymer composition.
2. The method of claim 1 , wherein reducing the collected expanded polymer composition into smaller particles includes moving the collected expanded polymer composition into a reducing apparatus using a directed fluid flow.
3. The method of claim 2 , wherein the collected expanded polymer composition is moved into the reducing apparatus by an applied vacuum.
4. The method of claim 1 , wherein the step of treating the reduced expanded polymer composition to yield an at least partially purified polymer composition includes heating the reduced expanded polymer composition.
5. The method of claim 4 , wherein the step of treating the reduced polymer composition to yield an at least partially purified recovered polymer composition includes degassing the reduced expanded polymer composition.
6. The method of claim 1 , further comprising feeding the at least partially purified recovered polymer composition into an extruding machine.
7. The method of claim 6 , further comprising forming extruded pellets from the at least partially purified recovered polymer composition.
8. The method of claim 7 , where forming extruded pellets from the at least partially purified recovered polymer composition includes adding one or more blowing agents to the at least partially purified recovered polymer composition.
9. The method of claim 1 , further comprising:
testing one or more mechanical properties of the collected at least partially purified recovered polymer composition, and
in response to a failure of one of the tested mechanical properties failing to meet established criteria, modifying the recovered polymer composition by adding one or both of (a) a polymer chain-extending additive, (b) virgin polymer composition.
10. The method of claim 9 , wherein testing one or more mechanical properties includes measuring an elongation at break of the at least partially purified recovered polymer composition.
11. The method of claim 1 , wherein the reduced expanded polymer composition is treated with the polar solvent also in order to remove one or both of (a) an unreacted chemical blowing agent, (b) reaction products of the reaction of a chemical blowing agent.
12. The method of claim 1 , wherein the one or more foaming agents include a surfactant.