Patent ID: 11884789
Assignee: THE BOEING COMPANY
Field: Other special machines (Mechanical engineering)
Classification: CPC C | IPC C

Claim 19:
20. A method of detecting damage to a prepreg composition due to UV radiation exposure, comprising:
a) forming a bed of fibers;
b) contacting the fiber bed with a resin matrix;
c) disposing a plurality of core/shell quantum dots on or in the resin matrix to form the prepreg composition, wherein:
each quantum dot includes an inner core covered by an outer shell;
the inner core is such that when excited by light of a first wavelength the inner core emits a detectable luminescent signal at a second wavelength;
the outer shell is such that it blocks light of the first wavelength from reaching the inner core when the outer shell is intact; and
the outer shell is such that it degrades upon exposure to UV radiation such that a detection of the luminescent signal at the second wavelength indicates that the quantum dot has been exposed to UV radiation; and

d) detecting the detectable luminescent signal from the plurality of core/shell quantum dots after exposure to an amount of UV radiation sufficient to render the prepreg composition unsuitable for use in fabricating composite structures.