Polyamide-based thermoplastic polymer compositions

Abstract

Polyamide-based thermoplastic polymer compositions that exhibit a good balance among the properties thereof, in particular their mechanical properties, and a high fluidity in the molten state; such compositions contain at least one high-fluidity polyamide and a shock modification agent having functional groups that react with the polyamide.

1 .- 13 . (canceled) 
   
   
       14 . A polymer composition comprising at least:
 a) a polyamide 6 or 66 obtained via a process of polymerization of the polyamide 6 or 66 monomers in the presence of monofunctional and/or difunctional compounds comprising carboxylic acid or amine functional groups, said polyamide having a melt flow index of greater than or equal to 10 g/10 min. according to the ISO1133 standard measured at a temperature of 275° C. with a load of 325 g; and   b) an impact modifier comprising functional groups that react with the polyamide a).   
   
   
       15 . The polymer composition as defined by  claim 14 , wherein the molecular weight Mn of the polyamide ranges from 3,000 to 25,000 g/mol. 
   
   
       16 . The polymer composition as defined by  claim 14 , wherein the polydispersity index of the polyamide is less than or equal to 2. 
   
   
       17 . The polymer composition as defined by  claim 14 , wherein the polyamide is obtained by adding, at the beginning, during or at the end of polymerization, aliphatic or aromatic, monocarboxylic or dicarboxylic acids and/or aliphatic or aromatic, monoamines or diamines. 
   
   
       18 . The polymer composition as defined by  claim 14 , wherein the polyamide has a melt flow index ranging from 10 to 50 g/10 min. 
   
   
       19 . The polymer composition as defined by  claim 14 , wherein the polyamide has a melt flow index ranging from 20 to 40 g/10 min. 
   
   
       20 . The polymer composition as defined by  claim 14 , wherein the impact modifiers are oligomeric or polymeric compounds comprising at least one of the following monomers, or a mixture thereof: ethylene, propylene, butene, isoprene, diene, acrylate, butadiene, styrene, octene, acrylonitrile, acrylic acid, methacrylic acid, vinyl acetate, vinyl esters such as acrylic and methacrylic esters, and glycidyl methacrylate. 
   
   
       21 . The polymer composition as defined by  claim 14 , wherein the impact modifiers comprise an elastomeric base selected from the group consisting of polyethylenes, polypropylenes, polybutenes, polyisoprenes, ethylene-propylene rubbers (EPRs), ethylene-propylene-diene rubbers (EPDMs), ethylene butene rubbers, ethylene acrylate rubbers, butadiene styrene rubbers, butadiene acrylate rubbers, ethylene octene rubbers, butadiene acrylonitrile rubbers, ethylene acrylic acids (EAAs), ethylene vinyl acetate (EVAs), ethylene acrylic esters (EEAs), acrylonitrile-butadiene-styrene (ABS) copolymers, styrene-ethylene-butadiene-styrene (SEBS) block copolymers, styrene-butadiene-styrene (SBS) copolymers, core-shell elastomers of methacrylate-butadiene-styrene (MBS) type, or blends of at least two of the elastomers listed above. 
   
   
       22 . The polymer composition as defined by  claim 14 , wherein the functional groups of the impact modifier, that are capable of reacting chemically with the polyamide a) are selected from the group consisting of acids, carboxylic acids, salified acids, esters, acrylates and methacrylates, ionomers, glycidyl groups, epoxy groups, glycidyl esters, anhydrides, maleic anhydrides, maleimides, and mixtures thereof. 
   
   
       23 . The polymer composition as defined by  claim 14 , wherein the impact modifiers are selected from the group consisting of ethylene/acrylic ester/glycidyl methacrylate terpolymers, ethylene/butyl ester acrylate copolymers, ethylene/n-butyl acrylate/glycidyl methacrylate copolymers, ethylene/maleic anhydride copolymers, maleic anhydride-grafted styrene/maleimide copolymers, copolymers of styrene/ethylene/butylene/styrene modified with maleic anhydride, maleic anhydride-grafted styrene/acrylonitrile copolymers, maleic anhydride-grafted acrylonitrile/butadiene/styrene copolymers, and hydrogenated congeners thereof. 
   
   
       24 . The polymer composition as defined by  claim 14 , wherein the proportion of impact modifiers present therein ranges from 0.1% to 10% by weight. 
   
   
       25 . The polymer composition as defined by  claim 14 , comprising at least one reinforcing and/or bulking filler. 
   
   
       26 . A method for producing a polymer composition as defined by  claim 14 , comprising melt blending said polyamide a) and said impact strength modifiers b). 
   
   
       27 . The polymer composition as defined by  claim 14 , comprising at least one polyamide 6. 
   
   
       28 . The polymer composition as defined by  claim 14 , comprising at least one polyamide 66. 
   
   
       29 . A shaped article product of reaction between the polyamide and the impact modifier as defined by  claim 14 . 
   
   
       30 . A shaped article product of reaction between the constituents of the polymer composition as defined by  claim 14 .