Apparatus and method for measuring in-situ crosslink density and crosslinked product and method of forming the same

A method for measuring an in-situ crosslink density, the method comprising:

• preparing a cross-linkable structure, the cross-linkable structure including a cross-linkable material and a crosslinking agent;
• irradiating the cross-linkable structure with a light configured to cross-link the cross-linkable structure;
• induce a stress-strain phase lag of the cross-linkable structure providing in-situ micro-deformation to the cross-linkable structure during the irradiating of the cross-linkable structure;
• and
• measuring the in-situ crosslink density of the cross-linkable structure from the stress-strain phase lag of the cross-linkable structure during the in-situ micro-deformation of the cross-linkable structure and the irradiating of the cross-linkable structure.

A method of manufacturing a crosslinked product, the method comprising:

• preparing a cross-linkable structure, the cross-linkable structure including a cross-linkable material and a crosslinking agent;
• and
• cross-linking the cross-linkable structure by irradiating light onto the cross-linkable structure,
• wherein the crosslinking of the cross-linkable structure comprises measuring an in-situ crosslink density of the cross-linkable structure by inducing a stress-strain phase lag of the cross-linkable structure by providing in-situ micro-deformation to the cross-linkable structure during the irradiating of the cross-linkable structure, and
• wherein the measuring the in-situ crosslink density of the cross-linkable structure is determined from the stress-strain phase lag of the cross-linkable structure during the in-situ micro-deformation of the cross-linkable structure and the irradiating of the cross-linkable structure.