Reusable expandable media with flexible skin for composite manufacturing and methods thereof
A material system including a plurality of expandable pellets or a monolithic flexible carrier is disclosed, each of which may include a polymer matrix configured to hold an expandable core, and a flexible skin configured to encapsulate the polymer matrix, and where the flexible skin is at least partially permeable with respect to the expandable core or a gas released by the expandable core. Implementations of the material system may include where the polymer matrix may include a thermoplastic polymer. The material system may include a charging source configured to introduce blowing agent. A method of curing a composite part is also described.
1. A material system, comprising:
a plurality of expandable pellets, comprising:
a polymer matrix configured to hold an expandable core; and
a flexible skin configured to encapsulate the polymer matrix; and
wherein the flexible skin is at least partially permeable with respect to the expandable core or a gas released by the expandable core.
2. The material system of claim 1 , wherein the polymer matrix comprises a thermoplastic polymer.
3. The material system of claim 1 , wherein the flexible skin comprises a thermoplastic elastomer (TPE).
4. The material system of claim 1 , further comprising a charging source configured to introduce blowing agent into one or more of the expandable pellets.
5. The material system of claim 1 , wherein the polymer matrix comprises polymethyl methacrylate (PMMA).
6. The material system of claim 1 , wherein a melting point of the polymer matrix is from about 200° F. to about 400° F.
7. The material system of claim 1 , wherein the flexible skin further comprises an outer coating comprising PTFE.
8. The material system of claim 1 , wherein a melting temperature of the flexible skin is from about 80° F. to about 370° F.
9. The material system of claim 1 , wherein a melting point of the polymer matrix is lower than a melting point of the flexible skin.
10. The material system of claim 4 , wherein the charging source further comprises dry ice.
11. The material system of claim 4 , wherein the blowing agent comprises carbon dioxide.
12. The material system of claim 4 , wherein the charging source further comprises a cartridge.
13. An expandable member system, comprising:
an expandable member comprising:
a polymer matrix configured to hold an expandable core; and
a flexible skin configured to encapsulate the polymer matrix and the expandable core; and
wherein the flexible skin is at least partially permeable with respect to the expandable core or a gas released by the expandable core.
14. The expandable member system of claim 13 , wherein the flexible skin comprises at least one of silicone, rubber, thermoplastic polyurethane (TPU), Polyethylene terephthalate (PET), polycarbonate (PC), and polyethylene (PE).
15. The expandable member system of claim 13 , wherein the polymer matrix comprises polymethyl methacrylate (PMMA).
16. The expandable member system of claim 13 , wherein the flexible skin further comprises an outer coating comprising PTFE.
17. The expandable member system of claim 13 , further comprising a flexible carrier configured to encapsulate the expandable member.
18. The expandable member system of claim 13 , further comprising a charging source configured to introduce blowing agent into the expandable member.
19. The expandable member system of claim 18 , wherein the charging source is external to the expandable member system.
20. A material system, comprising:
a plurality of expandable pellets, comprising:
a polymer matrix configured to hold an expandable core; and
a flexible skin configured to encapsulate the polymer matrix; and
wherein the flexible skin is impermeable with respect to the expandable core or a gas released by the expandable core.