Static dissipating resin composition and methods for manufacture thereof

Abstract

A substantially transparent antistatic, impact resistant, molding composition comprises a miscible mixture of a polycarbonate resin and a cycloaliphatic polyester resin, and an antistatic polymeric material wherein the mixture of the polycarbonate and the cycloaliphatic polyester resin is present in suitable proportions for substantially matching the index of refraction of the antistatic polymeric material.

1 . A transparent permanent electrostatic dissipating composition comprising in combination a transparent aromatic polycarbonate resin, a miscible transparent cycloaliphatic copolyester, and a sufficient amount of an electrostatic dissipating polymer for imparting electrostatic dissipative properties to said composition, said aromatic polycarbonate, said cycloaliphatic copolyester, and said electrostatic dissipating polymer, each having a predetermined index of refraction wherein said index of refraction of said electrostatic dissipating polymer has a refractive index value between said polycarbonate resin and said cycloaliphatic copolyester resin, said polycarbonate resin and said cycloaliphatic copolyester resin are present in said electrostatic composition for substantially matching the index of refration of said electrostatic dissipating polymer, said cycloaliphatic copolyester comprises the reaction product selected from the group consisting of (1) at least 80 weight % of cycloaliphatic diol with the remainder, if any, being a linear aliphatic diol, or a combination of a linear aliphatic diol and a linear aliphatic diacid, or chemical equivalents of the above, (2) at least 80 weight % of a cycloaliphatic dicarboxylic acid with the remainder, if any, being a linear aliphatic diacid, or a combination of a linear aliphatic diacid and a linear aliphatic diol or chemical equivalents of above, and (3) a mixture of at least 80 weight % of a cycloaliphatic diol and at least 80 weight % of a cycloaliphatic dicarboxylic acid with the remainder, if any, being a linear aliphatic diol or a linear aliphatic diacid or a mixture of the two, or chemical equivalents of the above.  
     
     
         2 . The composition of  claim 1  wherein ratio of cycloaliphatic copolyester to polycarbonate is from about 2.0 to about 1.6 and combined weight of polycarbonate and cycloaliphatic copolyester is 20 to 80% by weight of the total weight of the composition.  
     
     
         3 . The composition of  claim 1  wherein the electrostatic dissipating polymer is present in an amount of from 0.01 to about 25 weight % of the total weight of the composition.  
     
     
         4 . The composition of  claim 3  wherein the electrostatic dissipating polymer is present in an amount of 5 to 15 weight %  
     
     
         5 . The composition of  claim 1  wherein the cycloaliphatic diol is prepared from cycloaliphatic alkane diols of 2 to 12 carbon atoms.  
     
     
         6 . The composition of  claim 5  wherein the cycloaliphatic alkane diol is a 1,4-cyclohexyl primary diol.  
     
     
         7 . The composition of  claim 1  wherein the cycloaliphatic diacid is prepared from dicarbonylic acids having at least two carboxyl groups each of which is attached to a saturated carbon.  
     
     
         8 . The composition of  claim 7  wherein the diacid is selected from the group consisting of cyclo and biyclo aliphatic acids selected from the group consisting of decahydronaphthalene dicarboxylic acids, norbornene dicarboxylic acids, bicyclo octane dicarboxylic acids, 1,4-cyclohexanedicarboylic, and chemical equivalents thereof.  
     
     
         9 . The composition of  claim 1  wherein the cycloaliphatic copolyester is poly (1,4-cyclohexane-dimethanol-1,4-dicaroxylate).  
     
     
         10 . The composition of  claim 1  wherein the electrostatic dissipating polymer is selected from the group consisting of copolyesteramides, polyetherpolyamides, polyetheramide block copolymers, polyetherester-amide block copolymers, polyurethane containing a polyalkyalkylene glycol moeity, polyetheresters, and mixtures thereof.  
     
     
         11 . The composition of  claim 10  wherein the electrostatic dissipating polymer is a polyesteramide.  
     
     
         12 . The composition of  claim 10  wherein the electrostatic dissipating polymer is polyetheresteramide.  
     
     
         13 . The composition of  claim 1  wherein the composition has in addition thereto an impact modifier wherein the impact modifier has a refractive index similar to the refractive index of the composition of  claim 1 .  
     
     
         14 . The composition of  claim 13  wherein the impact modifier is a rubbery modifier.  
     
     
         15 . The impact modifier of  claim 14  wherein the impact modifier is a core-shell modifier having at least a partially cross-linked (meth) acrylate rubber core phase and an outer shall comprising an acrylic resin.  
     
     
         16 . The compositions of  claim 1  wherein the refractive index of the composition is 1.52 to 1.54.  
     
     
         17 . A substantially transparent antistatic, impact resistant, molding composition comprises a major portion by weight percent of a miscible mixture of a polycarbonate resin and a cycloaliphatic polyester resin, and an antistatic polymeric material wherein the mixture of the polycarbonate and the cycloaliphatic polyester resin is present in suitable proportions for substantially matching the index of refraction of the antistatic polymeric material.  
     
     
         18 . A substantially transparent antistatic molding composition according to  claim 17  including additional miscible resins wherein said miscible resins together with the polycarbonate and polyester resins form a mixture which substantially matches the index of refraction of the antistatic polymeric material.  
     
     
         19 . A substantially transparent antistatic molding composition according to claim 17 including an additional immiscible resin present in the molding composition, said additional immiscible resin desirable have an index of refraction substantially matching the index of refraction of the antistatic polymeric material.