Production of a polysuccinimide and derivatives thereof in the presence of a sulfur-containing dehydrating agent
AssigneeDonlar Corporation
InventorsDaniel A. Batzel, James F. Kneller, Abdul R. Y. Meah
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Abstract
Polysuccinimide of varying molecular weight has been prepared by heat polymerization of aspartic acid in the presence of a sulfur-containing dehydrating agent employing a variety of reaction mixtures and reaction conditions. Sulfur trioxide and heat decomposable sulfur trioxide precursor dehydrating agents are preferred for this purpose. The presence of an acid scavenger within the reaction mixture is desirable and leads to a relatively higher molecular weight polysuccinimide, while the absence of an acid scavenger results in a relatively lower molecular weight polysuccinimide.
Claims41
A method for preparing a polysuccinimide which comprises the steps of:
- (a) combining solid aspartic acid with a sulfur-containing dehydrating agent selected from the group consisting of sulfur trioxide, sulfur trioxide precursors, sulfur oxygen acids and salts thereof, and compounds containing a sulfonic acid group, to produce a reaction mixture;
- (b) polymerizing said reaction mixture by heating to a temperature sufficient to initiate polymerization;
- and
- (c) maintaining said polymerization temperature for a time period sufficient to effect polymerization of said aspartic acid to polysuccinimide.
A process for the production of polysuccinimide which comprises the steps of depositing a reaction mixture comprising aspartic acid and a sulfur-containing dehydrating agent selected from the group consisting of sulfur trioxide, sulfur trioxide precursors, sulfur oxygen acids and salts thereof, and compounds containing a sulfonic acid group, onto a plate type reactor, passing the deposited reaction mixture through a hot reaction zone at a temperature sufficient to initiate polymerization and for a time period sufficient to form a brittle solid that includes a thermally polymerized polysuccinimide, and thereafter recovering said thermally polymerized polysuccinimide from said reactor.
Dependencies are inferred from the claim text.