Patent ID: 8691911

Claim:
A melt-blended thermoplastic composition comprising A) a polyamide composition comprising a) 55 to 90 weight percent semi-crystalline semi-aromatic copolyamide having a melting point; wherein said semi-aromatic copolyamide comprises a-1) about 15 to 50 mole percent aromatic repeat units derived from: i) one or more aromatic dicarboxylic acids with 8 to 20 carbon atoms and a first aliphatic diamine with 4 to 20 carbon atoms; and a-2) 50 to 85 mole percent aliphatic repeat units derived from: ii) a first aliphatic dicarboxylic acid with 8 to 20 carbon atoms and said first aliphatic diamine with 4 to 20 carbon atoms; or iii) a first aliphatic aminoacid or lactam with 8 to 20 carbon atoms; wherein the semi-aromatic copolyamide has a DMA tan delta peak value of greater than or equal to 0.23; and heat of fusion of at least 20 J/g as measured in first heat cycle of DSC; b) 10 to 45 weight percent aliphatic homopolyamide having a melting point; wherein said aliphatic homopolyamide comprises repeat units derived from: iv) a second aliphatic dicarboxylic acid with 8 to 20 carbon atoms and a second aliphatic diamine with 4 to 20 carbon atoms or v) a second aliphatic aminoacid or lactam with 8 to 20 carbon atoms; and wherein the aliphatic homopolyamide has a DMA tan delta peak value of less than or equal to 0.21; and heat of fusion of at least 30 J/g as measured in first heat cycle of DSC; wherein the weight percent of a) and b) are based on the total weight of a) and b); and said first and second aliphatic diamines can be the same or different; B) 0 to 45 weight percent polymeric toughener; C) 0 to 20 weight percent, preferably 0 to 12 weight percent, plasticizers; and D) 0 to 45 weight percent reinforcing agent; wherein the weight percent of B), C), and D) are based on the total weight of the melt-blended thermoplastic composition; and wherein said melt-blend composition has a glass transition and has a tan delta peak (E″/E′) value of 0.21 or lower at said glass transition.