Photo-responsive macro- and micro- liquid marbles

Abstract

The invention relates to macro- and micro-liquid marbles (i.e. droplets of liquid with a particulate-based shell), and in particular, to photo-responsive macro- and micro-liquid marbles encapsulating a substance therein. Methods for forming the macro- and micro-liquid marbles, and use of the macro- and micro-liquid marbles, in controlled release applications are also disclosed.

1 . A method for releasing a substance from a macro- or micro-liquid marble, wherein the macro- or micro-liquid marble is formed by a plurality of nanoparticles and/or mixture of plurality of nanoparticles and said substance is encapsulated therein, the method comprising:
 irradiating the plurality of nanoparticles at a wavelength of between about 200 nm and about 2,000 nm, wherein each of the plurality of the nanoparticles is hydrophobic and/or oleophobic, wherein the plurality of nanoparticles comprises a material selected from the group consisting of an organic compound, a polymer, and a mixture thereof.   
     
     
         2 . The method as recited in  claim 1 , wherein the hydrophobic and/or oleophobic groups or molecules are selected from the group consisting of a silane, a silicone-based polymer, a fatty acid or a derivative thereof, an alkyl amine, and a mixture thereof. 
     
     
         3 . The method as recited in  claim 2 , wherein the hydrophobic molecules comprise a silane of formula RSi(OR′) 3 ,
 wherein 
 R is a C 6 -C 18  alkyl; and 
 R′ is a C 1 -C 3  alkyl. 
 
     
     
         4 . The method as recited in  claim 2 , wherein the hydrophobic molecules comprise a silane of formula RSiX 3 , R 2 SiX 2 , or R 3 SiX,
 wherein   R is a C 1 -C 18  alkyl; and   X is a halogen.   
     
     
         5 . The method as recited in  claim 2 , wherein the oleophobic molecules comprise a fluorinated or a perfluorinated fatty acid of formula RCOOH,
 wherein R is a fluorinated or a perfluorinated C 6 -C 18  alkyl.   
     
     
         6 . The method as recited in  claim 2 , wherein the oleophobic molecules comprise a fluorinated or a perfluorinated fatty acid chloride of formula RCOC 1 ,
 wherein R is a fluorinated or a perfluorinated C 6 -C 18  alkyl.   
     
     
         7 . The method as recited in  claim 5 , wherein R in RCOOH or RCOC 1  is CF 3 (CF 2 ) 5 CH 2 CH 2 — or CF 3 (CF 2 ) 7 CH 2 CH 2 —. 
     
     
         8 . The method as recited in  claim 1 , wherein the plurality of nanoparticles is comprised of a hydrophobic and/or an oleophobic polymer. 
     
     
         9 . The method as recited in  claim 1 , wherein the plurality of nanoparticles is comprised of an organic compound selected from the group consisting of an azo-containing compound, a stilbene-containing compound, and a mixture thereof. 
     
     
         10 . The method as recited in  claim 1  comprising:
 irradiating the plurality of nanoparticles at the wavelength of between about 200 nm and about 2,000 nm with an intensity of more than 0.01 mW/cm 2 . 
 
     
     
         11 . The method as recited in  claim 1 , wherein the substance encapsulated by the macro- or micro-liquid marble is in liquid phase. 
     
     
         12 . The method as recited in  claim 11 , wherein the substance comprises water or an aqueous solution. 
     
     
         13 . The method as recited in  claim 12 , wherein the substance further comprises a pharmaceutical active ingredient, an anti-oxidant, a dispersant, a fertilizer, a pesticide, a herbicide, or a mixture thereof. 
     
     
         14 . The method as recited in  claim 11 , wherein the substance comprises oil or an organic liquid. 
     
     
         15 . The method as recited in  claim 14 , wherein the substance further comprises a pharmaceutical active ingredient, an anti-oxidant, a dispersant, a fertilizer, a pesticide, a herbicide, or a mixture thereof.