Polymer preparation
The present disclosure relates to a preparation of polymer with improved color and properties. More particularly, the disclosure relates to the preparation of polyamide by introducing a polyetheramine additive during the polymer extrusion step. The extruded polymer is superior in appearance and spinnable in subsequent processing into yarn.
1. A process for making polyamide comprising:
a) feeding diacid and diamine to a first feed throat of a screw extruder, the screw extruder comprising a first melt zone and a first melt conveying zone downstream of the first feed throat;
b) at least partially polymerizing the diacid and the diamine to form a first polyamide;
c) feeding a polyetheramine additive to a second feed throat of the screw extruder downstream of the first melt conveying zone;
d) incorporating the polyetheramine additive with the first polyamide in a second melt zone and a second melt conveying zone; and
e) recovering a second polyamide from the screw extruder downstream from the second melt conveying zone, wherein:
i) the RV of the second polyamide using the or ASTM D789 method is from about 20 to about 60; or
ii) the amino end group (AEG) content is between about 15 mpmg and 130 mpmg;
wherein
the process further comprises feeding a second diacid to step (c) and incorporating the second diacid into the first polyamide in step (d), or
the polyetheramine additive comprises one or more additives, or
a combination thereof.
2. The process of claim 1 further comprising feeding a second diacid to step (c) and incorporating the second diacid into the first polyamide in step (d).
3. The process of claim 1 for making polyamide wherein, the polyetheramine additive is less thermally stable than the first polyamide.
4. The process of claim 1 for making polyamide wherein, the water regain of the second polyamide is greater than the water regain of the first polyamide.
5. The process of claim 1 for making polyamide wherein, the water regain of the second polyamide is >6 wt % to <30 wt %.
6. The process of claim 1 wherein the water regain of the second polyamide is from >10 wt % to <15 wt %.
7. The process of claim 1 for making polyamide wherein, the polyetheramine additive comprises one or more additives.
8. The process of claim 7 for making polyamide wherein the one or more additives comprise a catalyst.
9. The process of claim 8 for making polyamide wherein, the catalyst is chosen from a group consisting of phosphoric acid, phosphorous acid, hypophosphoric acid arylphosphonic acids, arylphosphinic acids, salts thereof, and mixtures thereof.
10. The process of claim 8 for making polyamide wherein, the catalyst is selected from a group consisting of sodium hypophosphite hydrate (SHP), manganese hypophosphite, sodium phenylphosphinate, sodium phenylphosphonate, potassium phenylphosphinate, potassium phenylphosphonate, hexamethylenediammonium bis-phenylphosphinate, potassium tolylphosphinate, and mixtures thereof.
11. The process of claim 1 further comprising adding an antioxidant or heat stabilizer to the first polyamide or the second polyamide.
12. The process of claim 11 wherein the antioxidant or heat stabilizer comprises a dicarboxylic acid.
13. The process of claim 12 wherein the dicarboxylic acid is adipic acid.