Adduct Thermosetting Surfacing Film and Method of Forming the Same

Abstract

In various embodiments, the invention provides an in-situ adduct formed by reacting liquid, solid, and/or semi-solid epoxy resins with a di-carboxylic acid functionalized polymer. The adducting process at least doubles the viscosity of the mixture. A hot melt thermosetting surfacing film and composite formed using the adduct are also disclosed. Methods of preparing and using are also disclosed.

1 .- 12 . (canceled) 
     
     
         13 . A resin composition for forming a thermosetting surfacing film, the composition comprising:
 a resin component comprising one or more epoxy resins selected from a liquid resin, a solid resin, a semi-solid resin and a combination thereof;   from about 1% to about 20% (by weight of the total composition) of a carboxylic acid functionalized polymer having an average functionality of about 2 or more carboxylic acids prior to reacting said polymer with said resin component;   from about 25% to about 60% (by weight of the total composition), with or without an organic surface treatment, of at least one filler material with a D90 particle size of between 1 and 30 microns,   said resin composition having a viscosity of less than about 100 Pa·s at 71° C., and being free of solvent.   
     
     
         14 . The composition of  claim 13 , wherein the one or more epoxy resins comprises:
 (A) from about 5% to about 60% (by weight of the total composition) of a resin fraction selected from a low viscosity liquid epoxy resin, and a combination of said low viscosity liquid epoxy resin with one or more resin selected from a solid resin, and a semi-solid; and   (B) from about 2% to about 40% (by weight of the total composition) of one or more solid bis-phenol A based epoxy resins having a softening point range from about 50° C. to about 130° C.   
     
     
         15 . The composition of  claim 13 , further comprising:
 (D) from about 0.001% to about 5% (by weight of the total composition) of a defoamer and/or air release agent.   
     
     
         16 . The composition of  claim 13 , further comprising:
 (F) from about 2% to about 10% (by weight of the total composition) of a curing agent.   
     
     
         17 . The composition of  claim 13 , further comprising:
 (G) from about 0.5% to about 5% (by weight of the total composition) of an accelerator or catalyst selected from a urea, a substituted urea, an imidazole, a substituted imidazole, a tertiary amine and a combination thereof.   
     
     
         18 . The resin composition according to  claim 13 , wherein the at least one filler has D90 particle size of less than 10 microns. 
     
     
         19 . The resin composition of  claim 13 , wherein the composition has a viscosity from about 20 Pa·s to about 100 Pa·s at 71° C. 
     
     
         20 . The resin composition of  claim 13 , wherein the filler material comprises is about 50% of the total composition(by weight). 
     
     
         21 . The resin composition of  claim 13 , wherein the at least one filler is aluminum trihydrate. 
     
     
         22 . A solvent-free surfacing resin composition which is prepared by:
 (A) reacting,
 (1) from about 5% to about 60% (by weight of the total composition) of a resin fraction selected from a low viscosity liquid epoxy resin and a combination of said low viscosity liquid epoxy resin, with one or more resin selected from a solid resin, and a semi-solid resin; 
 (2) from about 2% to about 40% (by weight of the total composition) of one or more solid bis-phenol A based epoxy resins having a softening point range from about 50° C. to about 130° C.; 
 (3) from about 1% to about 20% (by weight of the total composition) of a carboxylic acid functionalized polymer; 
   thereby forming an adduct; and   (B) mixing with said adduct,
 (1) from about 0.001% to about 5% (by weight of the total composition) of a defoamer and/or air release agent; and 
 (2) from about 25% to about 60% (by weight of the total composition), with or without an organic surface treatment, of at least one filler material having a D90 particle size of between 1 and 30 microns and optionally one or more pigments, 
 (3) from about 2% to about 10% (by weight of the total composition) of a curing agent; and 
 (4) from about 0.5% to about 5% (by weight of the total composition) of an accelerator or catalyst selected from a urea, a substituted urea, an imidazole, a substituted imidazole, a tertiary amine and a combination thereof, 
   thereby forming said resin composition.   
     
     
         23 . A solvent-free film product formed from the surfacing resin composition of  claim 22 , said product formed by a method comprising:
 (i) applying or coating the surfacing resin to a carrier to form a film product; and   (ii) after the applying, cooling the film product.   
     
     
         24 . The solvent-free surfacing resin composition of  claim 22 , wherein the carboxylic acid functionalized polymer has an average functionality of equal to or greater than about 2. 
     
     
         25 . The solvent-free surfacing resin composition of  claim 22 , wherein the carboxylic acid functionalized polymer is a di-carboxylic acid functionalized polymer. 
     
     
         26 . The solvent-free surfacing resin composition of  claim 22 , wherein the composition has a viscosity from about 20 Pa·s to about 100 Pa·s at 71° C.