Method for improving the paint adhesion of compatibilized polyphenylene ether-polyamide compositions

Abstract

Thermoplastic resin compositions are provided that comprise a thermoplastic resin and an amount of antioxidant effective to increase the adhesion of paint to an article made from the composition. Also provided are methods to improve the paint adhesion of articles wherein the articles have been subjected to a temperature of at least about 330° F. for period of at least about 10 minutes. In a preferred embodiment, the antioxidant, also known as a stabilizer, or mixture of stabilizers is selected from the group consisting of the phenolic antioxidants, the 3-arylbenzofuranones, the hindered amine stabilizers, the ultraviolet light absorbers, the alkaline metal salts of fatty acids, the hydrotalcites, the epoxydized soybean oils, the hydroxylamines, the tertiary amine oxides, thermal reaction products of tertiary amine oxides, the thiosynergists, and mixture containing at least one of the foregoing.

1 . A composition comprising: 
 a compatibilized polyphenylene ether polyamide composition;    carbon nanotubes, carbon black, or a combination comprising at least one of the foregoing;    about 1 to about 20 wt % of a saturated styrenic impact modifier; and    an amount of greater than or equal to 0.40 phr of an antioxidant, wherein the composition has been annealed at a temperature of greater than or equal to 165° C. for a time period of greater than or equal to 10 minutes; and wherein the composition has a specific volume resistivity of below 1×10 5  ohm-cm.    
     
     
         2 . The composition of  claim 1 , wherein the polyphenylene ether comprises a reaction product of 2,6-dimethylphenol and 2,3,6-trimethylphenol.  
     
     
         3 . The composition of  claim 2 , wherein a monomer weight ratio of 2,6-dimethylphenol to 2,3,6-trimethylphenol in the polyphenylene ether is about 1:3 to about 3:1.  
     
     
         4 . The composition of  claim 1 , comprising carbon nanotubes, wherein the carbon nanotubes have diameters of about 0.7 nanometers to about 500 nanometers.  
     
     
         5 . The composition of  claim 1 , wherein the carbon nanotubes are selected from the group consisting of single wall nanotubes, multi wall nanotubes and combinations comprising at least one of the foregoing carbon nanotubes.  
     
     
         6 . The composition of  claim 1 , further comprising impact modifiers selected from the group consisting of polystyrene-polybutadiene, polystyrene-polyisoprene, poly(α-methylstyrene)-polybutadiene, polystyrene-polybutadiene-polystyrene, polystyrene-polyisoprene-polystyrene, polystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer, polystyrene-poly(ethylene-propylene) diblock copolymer, poly(α-methylstyrene)-polybutadiene-poly(α-methylstyrene) and combinations comprising at least one of the foregoing impact modifiers.  
     
     
         7 . The composition of  claim 1 , wherein the antioxidant is selected from the group consisting of hindered phenols, thioesters, and combinations comprising at least one of the foregoing antioxidants.  
     
     
         8 . The composition of  claim 1 , wherein the antioxidants are selected from the group consisting of pentaerythritol tris ester with 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, pentaerythritol betalaurylthiopropionate and combinations comprising at least one of the foregoing antioxidants and wherein the antioxidants are added in amounts of about 0.5 to about 0.7 parts per hundred based upon the total weight of the composition.  
     
     
         9 . The composition of  claim 1 , wherein the antioxidants are selected from the group consisting of neopentanetetrayl tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate), n-octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 2,6-di-tert-butyl-p-cresol, 2,2′-ethylidene-bis(4,6-di-tert-butylphenol) and combinations comprising at least one of the foregoing antioxidants.  
     
     
         10 . The composition of  claim 1 , wherein the antioxidants are added in an amount of about 0.5 to about 0.7 parts per hundred, based upon the total weight of the composition.