Switching materials, and compositions and methods for making same

Abstract

A switching material comprising one or more than one polymers and an electrolyte comprising a salt and a solvent portion comprising one or more solvents; and one or more compounds having electrochromic and photochromic properties dispersed homogeneously through the switching material; and wherein the switching material is transitionable from a light state to a dark state on exposure to UV light and from a dark state to a light state with application of an electric voltage.

1 .- 46 . (canceled) 
     
     
         47 . A switching material comprising:
 a. one or more than one polymers;   b. an electrolyte comprising:
 i. a salt; and 
 ii. a solvent portion comprising one or more solvents; 
   c. a sacrificial solvent; and   d. one or more compounds having electrochromic and photochromic properties dispersed homogeneously through the electrolyte,   wherein the switching material is transitionable from a light state to a dark state on exposure to light comprising wavelengths of about 420 nm or less and from a dark state to a light state with application of an electric voltage.   
     
     
         48 . The switching material according to  claim 47  comprising, on a weight basis:
 a. about 2 wt % to about 15 wt % polymer; 
 b. about 0.1 wt % to about 5 wt % salt; 
 c. about 50 wt % to about 90 wt % solvent portion; 
 d. about 0.5 wt % to about 15 wt % of a compound having electrochromic and photochromic properties; and 
 e. about 1 to about 3 equivalents of sacrificial solvent to total polymer, salt, solvent portion and compound having electrochromic and photochromic properties, by weight. 
 
     
     
         49 . The switching material according to  claim 47  further comprising a crosslinking agent. 
     
     
         50 . The switching material according to  claim 47  wherein the one or more than one polymers are crosslinked with a crosslinking agent or with the crosslinking agent and an accelerant. 
     
     
         51 . The switching material according to  claim 47  wherein the switching material is soluble in the sacrificial solvent. 
     
     
         52 . The switching material according to  claim 47  wherein the switching material comprises from about 1.5 to about 2.5 equivalents of sacrificial solvent to total polymer, salt, solvent portion and compound having electrochromic and photochromic properties, by weight. 
     
     
         53 . The switching material according to  claim 47  wherein the sacrificial solvent has a boiling point at least 50° C. lower than the solvent portion and is non-reactive with the one or more than one polymers, the salt, the solvent portion and the one or more compounds having electrochromic and photochromic properties. 
     
     
         54 . The switching material of  claim 47  wherein the one or more than one polymers is a polyol, a polyvinyl acetal, a polyvinyl butyral or a combination thereof. 
     
     
         55 . The switching material of  claim 47  wherein the one or more polymers is a polyvinyl butyral having one or more of: a MW of from about 100 to about 300 k, a polyvinyl alcohol group content of from about 18% to about 21%, a polyvinyl acetate content of from about 0 to about 2.5%. 
     
     
         56 . The switching material of  claim 47  wherein the salt comprises a TFSI or BF 4  anion. 
     
     
         57 . The switching material of  claim 47  wherein the salt comprises an organic cation and the organic cation is a tetraalkyl ammonium, a tetraalkylphosphonium, a dialkylimidazolium, or a trialkylimidazolium cation, and wherein alkyl includes a group of from 1 to 10 carbons. 
     
     
         58 . The switching material of  claim 47  wherein the electrolyte has a potential range of from about −1.0V to about +1.5 V compared to an Ag/AgCl reference electrode. 
     
     
         59 . The switching material of  claim 47  wherein the solvent has one or more of the following:
 a. a boiling point of about 150° C. or greater; 
 b. a vapour pressure of about 0.001 mmHg or less at 20° C.; 
 c. a Yellowness Index (YI) of about 6 or less; 
 d. a flash point of about 80° C. or greater; and 
 e. a melting point of about 40° C. or less. 
 
     
     
         60 . The switching material of  claim 47  wherein the solvent portion comprises one or more than one of dimethyl 2-methylglutarate, 1,2-butylene carbonate, 1,2-propylene carbonate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, diethyl succinate, diethyl adipate, dimethyl adipate or a combination thereof. 
     
     
         61 . The switching material of  claim 47  wherein the crosslinking agent comprises one or more isocyanate groups. 
     
     
         62 . The switching material of  claim 47  wherein the one or more compounds having electrochromic and photochromic properties is a diarylethene. 
     
     
         63 . A method of making a switchable film comprising the steps of:
 a. providing a first part comprising one or more polymers, a salt, one or more compounds having photochromic and electrochromic properties, and a first portion of the solvent portion;   b. providing a second part comprising a second portion of the solvent portion, an optional crosslinking agent and an optional hardener;   c. providing a third part comprising a sacrificial solvent and an optional accelerant;   d. combining the first part and the second part;   e. combining the third part with the combined first and second parts to provide a coatable composition; and   f. applying the coatable composition to a substrate to form the switchable film.   
     
     
         64 . The method of  claim 63  wherein step f) is preceded by a step of partially curing the coatable composition. 
     
     
         65 . The method of  claim 63  wherein step f) further comprises curing the coatable composition. 
     
     
         66 . A method of making a laminated glass comprising:
 a. preparing a switchable material according to  claim 47 ;   b. applying a layer of the switching material onto a first substrate;   c. applying a second substrate to the layer of the switching material;   d. curing the layer of the switching material to form a switchable film;   e. positioning the switchable film within a stack of components comprising at least one layer of a hot-melt adhesive contacting an outer surface of the switchable film;   f. heating the unlaminated stack to a temperature of from about 90° C. to about 140° C. for at least 30 minutes.