Process for producing protective coating of siloxane resin and product produced

Abstract

Abstract THE PROCESS DESCRIBED HEREIN COMPRISES THE MIXING OF A SILOXANE PREPOLYMER HAVING REPEATING UNITS OF THE FORMULA -SI(-R")2-O- WITH 3-25 PARTS PER 100 OF PREPOLYMER OF A CURING AGENT COMPRISING AN AMINO-ALKYL-ALKOXYL-SILANE HAVING THE FORMMULA (R-)2-N-R''-SI(-R")N(-O-R")(3-N) WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, ALKYL, CYCLOALKYL AND AMINO-ALKYL RADICALS; R'' IS A DIVALENT HYDROCARBON RADICAL HAVING AT LEAST THREE CARBON ATOMS AND HAVING THE VALENCE BONDS WHICH ARE ATTACHED TO THE N AND SI OF THE FORMULA SEPARATED BY AT LEAST THREE CARBON ATOMS; R" IS A MONOVALENT HYDROCARBON RADICAL HAVING ONE TO SIX CARBON ATOMS; AND N IS AN INTEGER HAVING A VALUE OF 0-2. THESE COMPONENTS ARE MIXED IN AN INERT SOLVENT SUCH AS XYLENE OR TOLUENE IN A PROPORTION SO AS TO PRODUCE A SOLUTION OF APPROXIMATELY 50-60 PERCENT BY WEIGHT SOLIDS, ALLOWING THE COMPONENTS TO REACT IN SOLUTION FOR A PERIOD OF 30-60 MINUTES, THEREAFTER APPLYING THE SOLUTION AS A COATING ON A SOLID SUBSTRATE, AND CURING THE APPLIED FILM BY AIR-DRYING AT A TEMPERATURE OF ABOUT 20-40*C. THE COATING CURES IN A RELATIVELY SHORT TIME, EVEN WITHOUT MODIFIERS AND WITHOUT HEATING, TO A FILM CAPABLE OF WITHSTANDING TEMPERATURES OF 650*F. FOR EXTENDED PERIODS.

Inventors

• 👤 Robert L Stout

Bibliographic Details