Chain extension and branching of polyamides
The NEXAMITE® product range for polyamides/nylons offers melt strength and viscosity modification and is made up of linear chain extenders and long chain branching agents.
The linear chain extenders, NEXAMITE® A94 and A99 provide increased molecular weight during the melt processing of the polyamide. This effect is beneficial in e.g. extrusion applications of filaments, where process stabilization and increased mechanical properties are desired.
Another area where chain extension can be needed is when using recycled polyamide, r-PA. As with many recycled polymers, they lose part of their original performance when they are recycled, but a large portion of this can be restored by chain extension
NEXAMITE® A56 and NEXAMITE® A93 as long-chain branching agents which make them useful in for example blow-molding and extrusion applications. Unwanted effects, as for example parison sag, can be avoided by long chain branching but is also has a positive effect on the mechanical properties, such as flexural strength and modulus and increased elongation at break.
| Product name: | Polymers: | Effect: | Target application: |
| NEXAMITE® A56 | PA6.10, PA6.12, PA10.10, PA11, PA12, PA6, PA4.6, PA6.6 | Long-chain branching agent/ crosslinking agent | Injection/blow molding, pipe/tube extrusion |
| NEXAMITE® A93 | Long-chain branching agent | Injection/blow molding, pipe/tube extrusion | |
| NEXAMITE® A94 | Linear chain extender | Injection molding, filament extrusion r-PA | |
| NEXAMITE® A99 | Linear chain extender | Injection molding, filament extrusion, r-PA |
NEXAMITE® melt strength and viscosity modifier
Crosslinking of Polyamides
NEXAMITE® A32 and A33 can be used as cross-linkers for polyamides. NEXAMITE® A32 can be used alone for low molecular weight resins while it is recommended to use a combination of A32 and A33 for medium and high molecular weight resins.
Addition of these products to polyamide has little or no negative effect on processability during compounding and injection molding.
Effects achieved using NEXAMITE® A32/A33 include increased long term heat stability >180°C, reduced moisture uptake and increased tensile strength and modulus at temperatures >Tg. NEXAMITE® A32/A33 modified resins can, when combined with a post processing heat treatment stage, be used as an alternative to radiation cross-linked polyamides.
| Product name: | Polymers: | Effect: | Target application: |
| NEXAMITE® A32 | PA6, PA4.6, PA6.6 | End-capper/crosslinker | Injection molding |
| NEXAMITE® A33 | PA6, PA4.6, PA6.6 | Crosslinker | Injection molding |
NEXAMITE® for high temperature applications