High performance polyamide compounds and uses thereof
Disclosed herein are high performance semi-aromatic polyamide compounds having improved performance indicators for various applications, including alkaline battery end cap seal assembly applications. In one preferred embodiment, the disclosure relates to compounds comprising a semi-aromatic polyamide component comprising recurring terephthalamide and/or isophthalamide units, an impact modifier component comprising a modified polyolefin elastomer, one or more synergistic blends of sterically hindered phenolic stabilizers and phosphonates and one or more relatively high molecular weight organic phosphite stabilizers, and a fine talc nucleating agent.
1. A formed article obtained by forming a semi-aromatic polyamide resin composition comprising:
90 to 70 weight percent of at least one semi-aromatic polyamide;
5 to 25 weight percent of at least one modified polyolefin elastomer;
0.2 to 2 weight percent of a first heat stabilizer and a second heat stabilizer; and
0.1 to 2 weight percent of a nucleating agent,
wherein the at least one semi-aromatic polyamide has a melt temperature from 305° C. to about 343° C. and a glass transition temperature from 90° C. to 130° C.,
wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2.5:1 to about 1:1,
wherein the first heat stabilizer comprises one or more blends of sterically hindered phenolic stabilizers and phosphonates,
wherein the second heat stabilizer comprises bis (2,4-dicumylphenyl) pentaerythritol diphosphate, and
wherein the nucleating agent is a fine talc having an average particle diameter that does not exceed 1.5 μm.
2. The formed article of claim 1 wherein the semi-aromatic polyamide resin composition comprises 90 to 77 weight percent of at least one semi-aromatic polyamide, 8 to 20 weight percent of at least one modified polyolefin elastomer, 0.3 to 1.5 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2:1 to about 1.25:1.
3. The formed article according to claim 2 wherein the semi-aromatic polyamide resin composition comprises 84 to 83 weight percent of at least one semi-aromatic polyamide, 14.2 to 15.8 weight percent of at least one modified polyolefin elastomer, 0.4 to 1.0 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 1.67:1 to about 1.5:1.
4. The formed article according to claim 2 wherein the semi-aromatic polyamide comprises repeating units:
wherein R comprises an aliphatic radical having 4 to about 14 carbon atoms and the mole ratio of the units 1 and 2 ranges from about 0-100:0-100.
5. The formed article according to claim 2 wherein the modified polyolefin elastomer is a maleic-andydride-modified olefin copolymer.
6. A battery end cap seal assembly obtained by forming a semi-aromatic polyamide resin composition comprising:
90 to 70 weight percent of at least one semi-aromatic polyamide;
5 to 25 weight percent of at least one modified polyolefin elastomer;
0.2 to 2 weight percent of a first heat stabilizer and a second heat stabilizer; and
0.1 to 2 weight percent of a nucleating agent,
wherein the at least one semi-aromatic polyamide has a melt temperature from 305° C. to about 343° C. and a glass transition temperature from 90° C. to 130° C.,
wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2.5:1 to about 1:1,
wherein the first heat stabilizer comprises one or more blends of sterically hindered phenolic stabilizers and phosphonates,
wherein the second heat stabilizer comprises bis (2,4-dicumylphenyl) pentaerythritol diphosphate, and
wherein the nucleating agent is a fine talc having an average particle diameter that does not exceed 1.5 μm.
7. The battery end cap seal assembly according to claim 6 wherein the semi-aromatic polyamide resin composition comprises 90 to 77 weight percent of at least one semi-aromatic polyamide, 8 to 20 weight percent of at least one modified polyolefin elastomer, 0.3 to 1.5 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2:1 to about 1.25:1.
8. The battery end cap seal assembly according to claim 7 wherein the semi-aromatic polyamide resin composition comprises 84 to 83 weight percent of at least one semi-aromatic polyamide, 14.2 to 15.8 weight percent of at least one modified polyolefin elastomer, 0.4 to 1.0 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 1.67:1 to about 1.5:1.
9. The battery end cap seal assembly according to claim 7 wherein the semi-aromatic polyamide comprises repeating units:
wherein R comprises an aliphatic radical having 4 to about 14 carbon atoms and the mole ratio of the units 1 and 2 ranges from about 0-100:0-100.
10. The battery end cap seal assembly according to claim 7 wherein the modified polyolefin elastomer is a maleic-anhydride-modified olefin copolymer.
11. A semi-aromatic polyamide resin composition comprising:
90 to 70 weight percent of at least one semi-aromatic polyamide;
5 to 25 weight percent of at least one impact-modified polyolefin elastomer;
0.2 to 2 weight percent of a first heat stabilizer and a second heat stabilizer stabilizers; and
0.1 to 2 weight percent of a nucleating agent,
wherein the at least one semi-aromatic polyamide has a melt temperature from 305° C. to about 343° C. and a glass transition temperature from 90° C. to 130° C.,
wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2.5:1 to about 1:1,
wherein the first heat stabilizer comprises one or more blends of sterically hindered phenolic stabilizers and phosphonates,
wherein the second heat stabilizer comprises bis (2,4-dicumylphenyl) pentaerythritol diphosphate, and
wherein the nucleating agent is a fine talc having an average particle diameter that does not exceed 1.5 μm.
12. The semi-aromatic polyamide composition of claim 11 comprising 90 to 77 weight percent of at least one semi-aromatic polyamide, 8 to 20 weight percent of at least one modified polyolefin elastomer, 0.3 to 1.5 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 2:1 to about 1.25:1.
13. The semi-aromatic polyamide composition according to claim 12 comprising 84 to 83 weight percent of at least one semi-aromatic polyamide, 14.2 to 15.8 weight percent of at least one modified polyolefin elastomer, 0.4 to 1.0 weight percent of first and second heat stabilizers, and 0.1 to 1 weight percent nucleating agent, and wherein the ratio of the first heat stabilizer to the second heat stabilizer is from about 1.67:1 to about 1.5:1.
14. The semi-aromatic polyamide composition according to claim 12 wherein the semi-aromatic polyamide comprises repeating units:
wherein R comprises an aliphatic radical having 4 to about 14 carbon atoms and the mole ratio of the units 1 and 2 ranges from about 0-100:0-100.
15. The semi-aromatic polyamide composition according to claim 12 wherein the modified polyolefin elastomer is a maleic-anhydride-modified olefin copolymer.