The asymmetry and unique stereochemistry of Dytek® A, when used in polyamides, lowers melting points and glass transition temperatures without adversely affecting the mechanical properties compared to the corresponding linear homopolymers. These features greatly improve the processing of polyamide resins and allows for the development of new polyamide compositions with properties comparable to specialty polymers.
Improved Nylon Processing
Adding Dytek® A amine to a Nylon 6,6 polymer reduces melting temperature and reduces gelation in Nylon fiber and injection molding applications.
| Mole % Dytek® A | Melting temp, °C | Gel time, hours at 270°C |
|---|---|---|
| 0 | 265 | - |
| 5 | 256 | 77.5 |
| 10 | 247 | 94.4 |
| 17.5 | 228 | 120.1 |
| 20 | 225 | - |
- Time to “gel” substantially increased, without employing lower temperatures, or impacting fiber spinning performance
- Reduce extractables
- Decrease deposits on spinnerets (in fiber production)
- Less low molecular weight material
New Polyamide Compositions
Low Temperature Nylons (LTN)
Compared to related polyamides, polymers that contain Dytek® A exhibit unusually low melting points.
Melting Points of Nylon Homopolymers
| Monomer | Adipic Acid | Sebacic Acid | C12 diacid |
|---|---|---|---|
| C-5 Diamine | Nylon 5,6n223°Cn | Nylon 5,10n195°Cn | Nylon 5,12n170°Cn |
| Dytek® A | Nylon D,6n184°Cn | Nylon D,10n165°Cn | Nylon D,12n160°Cn |
| HMD | Nylon 6,6n265°Cn | Nylon 6,10n228°Cn | Nylon 6,12n217°Cn |
| C-10 Diamine | Nylon 10,6n236°Cn | Nylon 10,10n203°Cn | Nylon 10,12n192°Cn |
| C-12 Diamine | Nylon 12,6n236°Cn | Nylon 12,10n192°Cn | Nylon12,12n178°Cn |
| Melting temperature of Nylon 11 and Nylon 12 are ~180-190°C | |||
D,X polyamides are polymorphic and can be quenched to an amorphous state. Low Temperature Nylons (LTN) may be suitable for 3D printing applications, composites, hot melt adhesives, powder coatings, or as an alternative to Nylon 12.
Transparent Polyamides
Semi-aromatic polyamides made from DYTEK® A, terephthalic (PTA), and isophthalic acid (PIA).
DYTEK® A, PTA, and PIA polymers are can be used in transparent applications where polycarbonate struggles with chemical resistance or where costlier transparent polymers are over-specified.
Transparent Thermoplastic Comparison
| POLYCARBONATE | LOW-COST TRANSPARENT NYLONSn(E.G., NYLON 6I/6T)n | DYTEK® A, PTA, PIA | HIGH-COST TRANSPARENT NYLONSn(E.G., AMORPHOUS NYLON 12)n | |
|---|---|---|---|---|
| Relative Cost | $ | $$ | $ | $$ |
| Heat Resistance | +++ | + | ++ | +++ |
| Moisture Resistance | +++ | + | + | ++ |
| Transparency | ++ | ++ | ++ | +++ |
| Chemical Resistance1 | - | ++ | ++ | ++ |
| Scratch Resistance | - | + | ++ | |
| 1) Some hydrocarbons and fuels | ||||
| - | Poor |
| + | Good |
| ++ | Very Good |
| +++ | Excellent |
When used as a blend additive for traditional nylons, DYTEK® A, PTA, and PIA polymers can significantly improve conditioned mechanical properties for nylon 6,6 and nylon 6, including up to a 43% improvement in conditioned flexural strength and stiffness. DYTEK® A, PTA, and PIA polyamides can also be used as a blend additive to modify crystallinity, boost glass transition temperature, and improve dimensional stability.