Self-Invertible Emulsion Thickener for Pharmaceutical Formulations

The patent changes the molecular structure parameters of biobased polymers by introducing crosslinking points through glycidyl groups from epoxy compounds. This transforms linear polymer chains into three-dimensional networks, fundamentally altering the rheological properties and thickening capability of the biobased polymer in aqueous media

The patent creates a composite system combining biobased polymers (polyglutamic acid) with synthetic crosslinking agents (epoxy compounds). This hybrid approach leverages the environmental benefits of biobased materials while incorporating the effective crosslinking mechanism of synthetic agents to achieve superior thickening performance

The patent performs crosslinking reactions during the polymerization process itself, rather than as a separate post-processing step. The epoxy compounds are introduced into the reaction mixture, allowing crosslinking to occur concurrently with polymer chain formation, thereby simplifying the overall manufacturing process

The patent optimizes reaction parameters including pH control (maintaining pH 2-3 during crosslinking), temperature, and the molar ratio of epoxy compounds to monomers. These parameter optimizations enable effective crosslinking under controlled conditions that do not significantly complicate the manufacturing process

The patent creates a composite network structure where crosslinked polyglutamic acid forms a three-dimensional matrix in aqueous media. This network structure prevents polymer aggregation and phase separation, maintaining formulation stability even at high polymer concentrations where conventional biobased polymers would fail

The crosslinked regions create localized three-dimensional networks within the aqueous phase, providing stable thickening zones that prevent global formulation instability. The crosslinking creates micro-environments that maintain polymer solubility and distribution even at high overall concentrations