Malachite green based radio-chromic compounds and radiation sensing systems incorporating the compounds
Derivatized malachite green leuco dyes for use in radio-chromic systems are described. The dyes have the following structure: in which Ar is a substituted phenyl or thiophene ring in which at least one substitution of the Ar ring is not ortho to the bond between the ring and the linking carbon, and in which R 1 , R 2 , R 3 , and R 4 are independently selected from methyl, alkyl, or alkyl halide. The systems include the dyes in conjunction with an activator, e.g., a halogenated activator, and a carrier, e.g., a fluid carrier or an encapsulating polymeric matrix.
1. A radio-chromic system comprising: a derivatized leuco dye having the following structure:
in which
R1, R2, R3, and R4 are independently selected from the group consisting of alkyl and alkyl halide,
R5 and R9 are independently selected from the group consisting of H, C1 to C20 alkoxy, halogen, C1 to C20 halogen-functionalized alkyl, C1 to C20 alkylsilyl, sulfonyl; formyl, and carboxylate,
R7 is selected from the group consisting of H, C1 to C20 alkoxy, halogen, C1 to C20 halogen-functionalized alkyl, C1 to C20 alkylsilyl, sulfonyl, formyl, and carboxylate, or said R7 includes a phenyl ring,
R6 is C1 to C20 halogen-functionalized alkyl, and
R8 is C1 to C20 halogen-functionalized alkyl;
the radiochromic system further comprising a halogenated activator that forms a radical, a cationic species, or an anionic species upon absorption of radiation; and
the radiochromic system further comprising a polymeric matrix.
2. The radio-chromic system of claim 1 , the derivatized leuco dye being present in the system in an amount of from about 0.2 wt. % to about 50 wt. % by weight of the polymeric matrix.
3. The radio-chromic system of claim 1 , the derivatized leuco dye and the activator being present in the system in a weight ratio to one another of from about 500:1 to about 1:500.
4. A molded component comprising the radio-chromic system of claim 1 .
5. The molded component of claim 4 , wherein the molded component is an extruded component or an injection molded component.
6. A foam comprising the radio-chromic system of claim 1 .
7. A particle comprising the radio-chromic system of claim 1 .
8. A mixture comprising the particle of claim 7 dispersed in a fluid.
9. An additive manufactured structure comprising the radio-chromic system of claim 1 .
10. The system of claim 1 , wherein said R7 is methoxy or ethoxy.
11. The system of claim 1 , wherein said R7 is selected from the group consisting of a halogen and a C1 haloalkyl that includes three halogens substituted on the carbon.
12. The system of claim 1 , wherein the leuco dye has the following structure:
13. The system of claim 1 , wherein at least one of said R6 and said R8 is a C1 haloalkyl that includes three halogens substituted on the carbon.