Polyamides and corresponding polymer compositions and articles
Described herein are polyamides (PA) derived from the polycondensation of monomers in a reaction mixture comprising: (1) a diamine component (A) comprising 20 mol % to 95 mol % of a C 4 to C 12 aliphatic diamine, and 5 mol % to 80 mol % of a bis(aminoalkyl)cyclohexane, where mol % is relative to the total number of moles of all diamine monomers in the diamine component; and a dicarboxylic acid component (B) comprising: 30 mol % to 99 mol % of terephthalic acid and 1 mol % to 70 mol % of a cyclohexane dicarboxylic acid, wherein mol % is relative to the total number of moles of all dicarboxylic acid monomers in the dicarboxylic acid component. It was surprisingly discovered that, with the particular combination of the bis(aminoalkyl)cyclohexane and the cyclohexanedicarboxylic acid, the polyamides (PA) had, on the whole, improved thermal performance relative to analogous polyamides, in which the cyclohexanedicarboxylic acid is replaced with an aromatic dicarboxylic acid.
1. A semi-crystalline polyamide derived from the polycondensation of monomers in a reaction mixture comprising:
a diamine component comprising:
50 mol % to 95 mol % of a C 4 to C 12 aliphatic diamine,
5 mol % to 50 mol % of bis(aminoalkyl)cyclohexane,
wherein mol % is relative to the total number of moles of all diamines in the diamine component;
a dicarboxylic acid component comprising:
45 mol % to 99 mol % of terephthalic acid,
1 mol % to 55 mol % of cyclohexanedicarboxylic acid,
wherein mol % is relative to the total number of moles of all dicarboxylic acids in the dicarboxylic acid component;
wherein the C 4 to C 12 aliphatic diamine is 1,6-diaminohexane.
2. The polyamide of claim 1 , wherein the bis(aminoalkyl)cyclohexane is 1,3-bis(aminomethyl)cyclohexane or 1,4-bis(aminomethyl)cyclohexane.
3. The polyamide of claim 2 , wherein the cyclohexanedicarboxylic acid is 1,4-cyclohexanedicarboxylic acid.
4. The polyamide of claim 1 , wherein the dicarboxylic acid component further comprises an additional dicarboxylic acid selected from the group consisting of C 4 to C 12 aliphatic dicarboxylic acids, aromatic dicarboxylic acids and cycloaliphatic dicarboxylic acids.
5. The polyamide of claim 4 , wherein:
The C 4 to C 12 aliphatic dicarboxylic acid is selected from the group consisting of: succinic acid [HOOC—(CH 2 ) 2 —COOH], glutaric acid [HOOC—(CH 2 ) 3 —COOH], 2,2-dimethyl-glutaric acid [HOOC—C(CH 3 ) 2 —(CH 2 ) 2 —COOH], adipic acid [HOOC—(CH 2 ) 4 —COOH], 2,4,4-trimethyl-adipic acid [HOOC—CH(CH 3 )—CH 2 —C(CH 3 ) 2 —CH 2 —COOH], pimelic acid [HOOC—(CH 2 ) 5 —COOH], suberic acid [HOOC—(CH 2 ) 6 —COOH], azelaic acid [HOOC—(CH 2 ) 7 —COOH], sebacic acid [HOOC—(CH 2 ) 5 —COOH], 1,12-dodecanedioic acid [HOOC—(CH 2 ) 10 —COOH];
the aromatic dicarboxylic acid is selected from the group consisting of: phthalic acids, including isophthalic acid (IA), naphthalenedicarboxylic acids, 4,4′ bibenzoic acid, 2,5-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, 2,2-bis(4-carboxyphenyl)propane, 2,2-bis(4-carboxyphenyl)hexafluoropropane, 4,4′-bis(4-carboxyphenyl)sulfone, 2,2-bis(4-carboxyphenyl)ketone, 2,2-bis(3-carboxyphenyl)propane, 2,2-bis(3-carboxyphenyl)hexafluoropropane, 2,2-bis(3-carboxyphenyl)ketone, bis(3-carboxyphenoxy)benzene; and
the cycloaliphatic dicarboxylic acid is selected from the group consisting of:
cyclopropane-1,2-dicarboxylic acid, 1-methylcyclopropane-1,2-dicarboxylic acid, cyclobutane-1,2-dicarboxylic acid, tetrahydrofuran-2,5-dicarboxylic acid, 1,3-adamantanedicarboxylic acid.
6. The polyamide of claim 1 , comprising a heat of fusion of at least 30 J/g, as measured according to ASTM D3418 using a heating rate of 20° C./minute.
7. The polyamide of claim 1 , comprising a glass transition temperature of at least 145° C., as measured according to ASTM D3418.
8. The polyamide of claim 1 , comprising a melting temperature of at least 295° C., as measured according to ASTM D3418.
9. The polyamide of claim 1 , exhibiting a glass transition temperature Tg of at least 150° C. and a melting temperature Tm of at least 300° C., as measured according to ASTM D3418.