Weatherable resinous composition with low heat storage and method

Abstract

Disclosed are compositions comprising: (i) a rubber modified thermoplastic resin comprising a discontinuous elastomeric phase dispersed in a rigid thermoplastic phase, wherein the elastomeric phase comprises a polymer having structural units derived from at least one (C 1 -C 12 )alkyl(meth)acrylate monomer; and wherein the rigid thermoplastic phase comprises structural units derived from at least one vinyl aromatic monomer and at least one monoethylenically unsaturated nitrile monomer; and (ii) a colorant combination comprising at least one inorganic infrared reflecting pigment and at least one organic colorant, wherein the combination of the inorganic pigment and organic colorant results in a molded part with an L* value of less than about 30 with specular component included, and a heating build-up (HBU) as measured according to ASTM D4803-89 of less than about 34° C. A method to make such compositions is also an embodiment of the invention as are articles made from such compositions.

1 . A composition comprising: (i) a rubber modified thermoplastic resin comprising a discontinuous elastomeric phase dispersed in a rigid thermoplastic phase, wherein at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase; and wherein the elastomeric phase comprises a polymer having structural units derived from at least one (C 1 -C 12 )alkyl(meth)acrylate monomer; and wherein the rigid thermoplastic phase comprises structural units derived from at least one vinyl aromatic monomer and at least one monoethylenically unsaturated nitrile monomer; and 
 (ii) a colorant combination comprising at least one inorganic infrared reflecting pigment and at least one organic colorant, wherein the combination of the inorganic pigment and organic colorant results in a molded part with an L* value of less than about 30 with specular component included, and a heating build-up (HBU) as measured according to ASTM D4803-89 of less than about 34° C.    
     
     
         2 . The composition of  claim 1 , wherein the elastomeric phase comprises structural units derived from butyl acrylate.  
     
     
         3 . The composition of  claim 1 , wherein the rigid thermoplastic phase comprises structural units derived from styrene and acrylonitrile; or styrene, alpha-methyl styrene, and acrylonitrile.  
     
     
         4 . The composition of  claim 1 , wherein the rigid thermoplastic phase further comprises structural units derived from one or more monomers selected from the group consisting of (C 1 -C 12 )alkyl- and aryl-(meth)acrylate monomers.  
     
     
         5 . The composition of  claim 4 , wherein the rigid thermoplastic phase comprises structural units derived from styrene, acrylonitrile, and methyl methacrylate; or alpha-methyl styrene, acrylonitrile and methyl methacrylate; or styrene, alpha-methyl styrene, acrylonitrile and methyl methacrylate.  
     
     
         6 . The composition of  claim 1 , wherein a copolymer comprising structural units derived from styrene and acrylonitrile; alpha-methylstyrene and acrylonitrile; alpha-methylstyrene, styrene, and acrylonitrile; styrene, acrylonitrile, and methyl methacrylate; alpha-methyl styrene, acrylonitrile, and methyl methacrylate; or alpha-methylstyrene, styrene, acrylonitrile, and methyl methacrylate is added to the rubber modified thermoplastic resin.  
     
     
         7 . The composition of  claim 1 , wherein the inorganic infrared reflecting pigment comprises: a metal oxide, a mixed metal oxide, a titanate, an aluminate, a metal carbonate, an iron oxide, a chromium oxide, an ultramarine, stainless steel powder, mica powder covered with titanium oxide, a metal sulfide, or a rare-earth sulfides.  
     
     
         8 . The composition of  claim 7 , wherein the inorganic infrared reflecting pigment is selected from the group consisting of a chromium iron oxide, a black spinel, and chrome iron nickel black spinel.  
     
     
         9 . The composition of  claim 7 , wherein the inorganic infrared reflecting pigment is present in an amount greater than or equal to about 0.05 parts per hundred parts resinous components by weight (phr).  
     
     
         10 . The composition of  claim 1 , wherein the organic colorant is derived from an anthraquinone, an azo, a phthalic anhydride, a phthalocyanine, an indigo/thioindigo, an azomethine, an azomethine-azo, a dioxazine, a quinacridone, an isoindolinone, an isoindoline, a diketopyrrolopyrrole, a perylene, or a perinone organic colorant, or mixtures thereof.  
     
     
         11 . The composition of  claim 1 , wherein the organic colorant comprises at least one colorant selected from the group consisting of Solvent Green 3, Solvent Red 135, Solvent Violet 13, Pigment Blue 15:4, Pigment Black 31, Disperse Violet 31/26, and mixtures thereof.  
     
     
         12 . The composition of  claim 11 , comprising at least two organic colorants.  
     
     
         13 . The composition of  claim 1 , wherein the total loading of organic colorant is greater than or equal to about 0.5 phr.  
     
     
         14 . The composition of  claim 1 , further comprising an additive selected from the group consisting of lubricants, neutralizers, stabilizers, heat stabilizers, light stabilizers, antioxidants, UV screeners, UV absorbers, and mixtures thereof.  
     
     
         15 . An article made from the composition of  claim 1 .  
     
     
         16 . A composition comprising: (i) a rubber modified thermoplastic resin comprising a discontinuous elastomeric phase dispersed in a rigid thermoplastic phase, wherein at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase; and wherein the elastomeric phase comprises a polymer having structural units derived from butyl acrylate; and wherein the rigid thermoplastic phase comprises structural units derived from styrene, acrylonitrile, and optionally methyl methacrylate, and 
 (ii) a colorant combination comprising an inorganic infrared reflecting pigment and at least two organic colorants, wherein the inorganic infrared reflecting pigment is selected from the group consisting of a chromium iron oxide, a black spinel, and chrome iron nickel black spinel, and is present in an amount greater than or equal to about 0.05 phr;    and wherein the organic colorant comprises at least two colorants selected from the group consisting of Solvent Green 3, Solvent Red 135, Solvent Violet 13, Pigment Blue 15:4, Pigment Black 31, and Disperse Violet 31/26, and is present in a total amount greater than or equal to about 0.5 phr;    and wherein the combination of the inorganic pigment and organic colorant results in a molded part with an L* value of less than about 30 with specular component included, and a heating build-up (HBU) as measured according to ASTM D4803-89 of less than about 34° C.    
     
     
         17 . The composition of  claim 16 , wherein a copolymer comprising structural units derived from styrene and acrylonitrile; alpha-methylstyrene and acrylonitrile; alpha-methylstyrene, styrene, and acrylonitrile; styrene, acrylonitrile, and methyl methacrylate; alpha-methyl styrene, acrylonitrile, and methyl methacrylate; 
 or alpha-methylstyrene, styrene, acrylonitrile, and methyl methacrylate is added to the rubber modified thermoplastic resin.    
     
     
         18 . The composition of  claim 16 , further comprising an additive selected from the group consisting of lubricants, neutralizers, stabilizers, heat stabilizers, light stabilizers, antioxidants, UV screeners, UV absorbers, and mixtures thereof.  
     
     
         19 . An article made from the composition of  claim 16 .  
     
     
         20 . A method for preparing an article comprising a rubber modified thermoplastic resin comprising a discontinuous elastomeric phase dispersed in a rigid thermoplastic phase, wherein at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase; and wherein the elastomeric phase comprises a polymer having structural units derived from butyl acrylate; and wherein the rigid thermoplastic phase comprises structural units derived from styrene, acrylonitrile, and optionally methyl methacrylate, wherein the article has an L* value of less than about 30 with specular component included, and a heating build-up (HBU) as measured according to ASTM D4803-89 of less than about 34° C.; 
 which method comprises the step of combining the resin with a colorant combination comprising an inorganic infrared reflecting pigment and at least two organic colorants, wherein the inorganic infrared reflecting pigment is selected from the group consisting of a chromium iron oxide, a black spinel, and chrome iron nickel black spinel, and is present in an amount greater than or equal to about 0.05 phr;    and wherein the organic colorant comprises at least two colorants selected from the group consisting of Solvent Green 3, Solvent Red 135, Solvent Violet 13, Pigment Blue 15:4, Pigment Black 31, Disperse Violet 31/26, and mixtures thereof, and is present in a total amount greater than or equal to about 0.5 phr.    
     
     
         21 . The method of  claim 20 , wherein the rigid thermoplastic phase comprises structural units derived from methyl methacrylate.  
     
     
         22 . The method of  claim 20 , wherein a copolymer comprising structural units derived from styrene and acrylonitrile; alpha-methylstyrene and acrylonitrile; 
 alpha-methylstyrene, styrene, and acrylonitrile; styrene, acrylonitrile, and methyl methacrylate; alpha-methyl styrene, acrylonitrile, and methyl methacrylate; or alpha-methylstyrene, styrene, acrylonitrile, and methyl methacrylate is added to the rubber modified thermoplastic resin.    
     
     
         23 . The method of  claim 20 , further comprising an additive selected from the group consisting of lubricants, neutralizers, stabilizers, heat stabilizers, light stabilizers, antioxidants, UV screeners, UV absorbers, and mixtures thereof.