Reusable expandable media with flexible skin for composite manufacturing and methods thereof

A method of curing a composite part, comprising:

• introducing a blowing agent into an expandable material to place the expandable material in a charged state;
• contacting the expandable material with an internal cavity of an uncured composite part;
• subjecting the expandable material and the internal cavity of the uncured composite part to a first temperature such that the expandable material transitions from a charged state to an activated state;
• maintaining the expandable material at the first temperature and in the charged state until the uncured composite part is a cured composite part;
• cooling the expandable material and the cured composite part to a second temperature;
• and
• wherein the expandable material comprises a polymer matrix configured to hold the blowing agent, and a flexible skin configured to:
• encapsulate the polymer matrix;
• and
• restrict escape of the blowing agent to control an expansion of the expandable material.

A method of curing a composite part, comprising:

• introducing a blowing agent into an expandable material to place the expandable material in a charged state;
• contacting the expandable material with an uncured composite part, wherein the uncured composite part is contained in a mold;
• subjecting the expandable material and the uncured composite part to a first temperature such that the expandable material transitions from the charged state to an activated state;
• maintaining the expandable material at the first temperature and in a charged state until the uncured composite part is a cured composite part;
• cooling the expandable material and the cured composite part to a second temperature;
• separating the expandable material from the cured composite material;
• and
• exposing the expandable material to a recovery condition;
• and
• wherein:
• the expandable material comprises a polymer matrix configured to hold the blowing agent, and a flexible skin configured to:
• encapsulate the polymer matrix;
• and
• restrict escape of the blowing agent to control an expansion of the expandable material.