Formulation Issue: Incompatibility between Pro Polymer and Eye Preserved

The problem you experienced with your gel liquefying, becoming cloudy, and forming precipitates after adding Eye Preserved is due to an incompatibility between the gelling agent, Pro Polymer, and the preservative, Eye Preserved.

• Pro Polymer is an anionic polymer thickener.
• Eye Preserved (Polyhexamethylene Biguanide, PHMB) is a cationic ingredient and an electrolyte.

Cationic ingredients are incompatible with anionic polymers. When Eye Preserved was added, its positive charges reacted with the negative charges of the Pro Polymer network. This interaction disrupted the gel structure, causing it to break down and become liquid. The cloudiness and precipitation are a result of insoluble complexes forming between the cationic preservative and the anionic polymer.

This incompatibility absolutely affects the effectiveness of your formula. The loss of the gel structure and the formation of precipitates mean the ingredients are not properly dispersed, which can reduce the performance and stability of the product.