Golf club head comprising glass bubble fill material

A method comprising the steps of:

• providing a golf club head comprising a body having at least one cavity;
• providing a polymer material;
• providing a plurality of microscopic glass bubbles;
• combining the plurality of microscopic glass bubbles with the polymer material to create a fill material;
• and
• injecting the fill material into the at least one cavity of the golf club head,
• wherein the plurality of microscopic glass bubbles constitutes 5-70% of a volume of the fill material.

A method comprising the steps of:

• providing a golf club head comprising a body having at least one cavity;
• providing a polymer material;
• providing an agent material selected from the group consisting of a curative and a catalyst;
• providing a plurality of microscopic glass bubbles;
• combining the plurality of microscopic glass bubbles with the agent material to create an intermediary material;
• combining the intermediary material with the polymer material to create a fill material;
• and
• injecting the fill material into the at least one cavity of the golf club head,
• wherein the plurality of microscopic glass bubbles constitutes 5-70% of a volume of the intermediary material.

A method comprising the steps of:

• providing a golf club head comprising a body having at least one cavity;
• providing a polymer material having a Poisson's ratio of 0.40-0.50;
• providing an agent material selected from the group consisting of a curative and a catalyst;
• providing a plurality of microscopic glass bubbles;
• combining the polymer material with the agent material to form an intermediary material;
• combining the plurality of microscopic glass bubbles with the intermediary material to create a fill material;
• injecting the fill material into the at least one cavity of the golf club head;
• and
• curing the fill material within the golf club head,
• wherein the plurality of microscopic glass bubbles constitutes 5-70% of a volume of the fill material.