Process for making pre-gels for a cross-linked branched polyester
AssigneeEastman Chemical Company
InventorMichael D. Hamlin
Life of this patent
Estimating the term…
Abstract
The invention relates to a process for making a high molecular weight pre-gel for a cross-linked branched polyester comprising: a) reacting polyester precursor repeat units via condensation polymerization in a continuous or semi-continuous, or batch reactor stage to form a low molecular weight pre-gel; and b) further reacting the low molecular weight pre-gel via condensation polymerization in a continuous thin-film reactive vacuum processing stage to form a high molecular weight pre-gel.
Claims32
A process for making a high molecular weight pre-gel for a crosslinked branched polyester comprising:
- a) reacting polyester precursor repeat units formed from (1) at least one polyol having three or more hydroxyl groups or esters thereof;
- and (2) at least one aliphatic or aromatic polyfunctional acid or ester thereof, or a mixture thereof, wherein the reaction is conducted via condensation polymerization in a continuous or semi-continuous, or batch reactor stage to form a pre-gel having a molecular weight of from about 1000 to 4000 weight average molecular weight, thereby providing a low molecular weight pre-gel;
- and
- b) further reacting the low molecular weight pre-gel via condensation polymerization in a continuous thin-film reactive vacuum processing stage to form a pre-gel having a molecular weight of about greater than 5000 weight average molecular weight, thereby providing a high molecular weight pre-gel.
The process of 13, wherein the crosslinked polyester gel is directed into a product container.
The process of claim of 30, wherein the aliphatic or aromatic polyfunctional acid or ester has three functional groups.
Dependencies are inferred from the claim text.