Processes for removal of color bodies from polytrimethylene ether glycol polymers
AssigneeE.I. du Pont de Nemours and Company
InventorsHari Sunkara, Hiep Do
Life of this patent
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Abstract
Processes for reducing color in PO3G are provided. The processes include contacting PO3G with an adsorbent and then separating the PO3G from the adsorbent by, for example, filtration. The process provides PO3G having an APHA color preferably less than about 50. The processes are desirably used for polymers having a molecular weight of about 250 to about 5000.
Claims26
A process comprising contacting PO3G having color with adsorbent and separating the PO3G and adsorbent, wherein the PO3G, after contact with the adsorbent, has a APHA color of less than about 50, said PO3G having molecular weight of about 250 to about 5000.
A process comprising:
- (a) providing reactant comprising 1,3-propanediol and polycondensation catalyst;
- (b) polycondensing the reactant to PO3G having color;
- (c) contacting the PO3G with adsorbent;
- and
- (d) separating the PO3G and adsorbent, such that the PO3G, after contact with the adsorbent, has a APHA color of less than about 50.
A process comprising contacting PO3G with adsorbent and separating the PO3G and adsorbent, wherein the PO3G has an APHA color, before contact with adsorbent, of about 70 to about 300, wherein the PO3G, after contact with the adsorbent, has an APHA color of less than about 50.
Dependencies are inferred from the claim text.