Chemical agent resistant coating compositions

Abstract

A chemical agent resistant coating composition can include a fluoropolymer, a flatting agent, and a hydrophobic additive. When the composition is applied to a substrate and cured as a coating, the coating has an 85° gloss of less than 3.5, a water contact angle of greater than 80°, and desorbs a maximum of 180 micrograms of bis(2-chloroethyl) sulfide and a maximum of 40 micrograms of O-pinacolyl methylphosphonofluoridate, according to testing under MIL-PRF-32348. A method of preparing chemical agent resistant coating compositions and substrates at least partially coated with the chemical agent resistant coating compositions are also disclosed.

The invention claimed is: 
     
         1 . A chemical agent resistant coating composition comprising:
 a fluoropolymer,   a flatting agent comprising at least 10 weight % based on the total solids weight of the coating composition; and   a hydrophobic additive comprising a wax,   wherein when the composition is applied to a substrate and cured as a coating, the coating has an 85° gloss of less than 3.5, a water contact angle of greater than 80°, and desorbs a maximum of 180 micrograms of bis(2-chloroethyl) sulfide and a maximum of 40 micrograms of O-pinacolyl methylphosphonofluoridate, according to testing under MIL-PRF-32348.   
     
     
         2 . The coating composition of  claim 1 , wherein the coating has a water contact angle of greater than 100°. 
     
     
         3 . The coating composition of  claim 1 , wherein the coating desorbs a maximum of 80 micrograms of bis(2-chloroethyl) sulfide and a maximum of 35 micrograms of O-pinacolyl methylphosphonofluoridate. 
     
     
         4 . The coating composition of  claim 1 , wherein the fluoropolymer comprises polyvinylidene fluoride, chlorotrifluoroethylene copolymer, or a combination thereof. 
     
     
         5 . The coating composition of  claim 1 , wherein the flatting agent comprises a metal hydroxide, metal oxide, silica, a hyperbranched (meth)acrylic polymer, a polyurea particle, a polyolefin particle, ground fiberglass, or mixtures thereof. 
     
     
         6 . The coating composition of  claim 1 , wherein the fiberglass comprises an average size dimension of 30 to 70 microns. 
     
     
         7 . The coating composition of  claim 1 , wherein the wax is a fluorinated wax. 
     
     
         8 . The coating composition of  claim 1 , wherein the wax comprises polytetrafluoroethylene wax, polytetrafluoroethylene-modified polyethylene wax, polytetrafluoroethylene-modified polypropylene wax, polyethylene wax, polypropylene wax, paraffinic wax, carnauba wax, silicone wax, or combinations thereof. 
     
     
         9 . The coating composition of  claim 1 , wherein the coating composition further comprises a dispersible acrylic resin. 
     
     
         10 . The coating composition of  claim 9 , wherein the acrylic resin has an acid value of 10 to 100 mg KOH/g. 
     
     
         11 . The coating composition of  claim 9 , wherein the acrylic resin comprises greater than 50 weight % methyl (meth)acrylate based on the total weight of the acrylic resin. 
     
     
         12 . The coating composition of  claim 9 , wherein the acrylic resin has a glass transition temperature of greater than 40° C. 
     
     
         13 . The coating composition of  claim 1 , wherein the coating composition is a powder coating composition. 
     
     
         14 . The coating composition of  claim 1 , wherein the coating composition further comprises a crosslinker. 
     
     
         15 . The coating composition of  claim 1 , wherein the coating composition is completely free of a crosslinker. 
     
     
         16 . A substrate at least partially coated with the coating composition of  claim 1 . 
     
     
         17 . A method of preparing a chemical agent resistant coating composition comprising mixing a fluoropolymer, a flatting agent such that the flatting agent comprises at least 10 weight % of the composition based on the total solid weight of the coating composition, and a hydrophobic additive comprising a wax, wherein when the coating composition is applied to a substrate and cured as a coating, the coating has an 85° gloss of less than 3.5, a water contact angle of greater than 800, and desorbs a maximum of 180 micrograms of bis(2-chloroethyl) sulfide and a maximum of 40 micrograms of O-pinacolyl methylphosphonofluoridate, according to testing under MIL-PRF-32348. 
     
     
         18 . The method of  claim 17 , further comprising dispersing the mixture in water. 
     
     
         19 . The method of  claim 17 , further comprising drying the mixture to form a powder coating composition.