Cationic silicone polymers

corresponding

TONY O’LENICK
Siltech LLC, Lawrenceville, USA

Abstract

Traditional (fatty) cationic compounds, referred to as quats, are used very commonly in the personal care industry as conditioners and softeners on the hair and skin. This is due to the fact that hair and skin have a net negative charge and as a result of ionic interactions, the positively charged quats become substantive to the hair and skin (1).
It is therefore not surprising that the silicone analogues of traditional quats are likewise important compounds in personal care vis-à-vis conditioning and softening. The structure of the compound and the balance of silicone, fatty and water-soluble groups determine the properties of silicone quats, as is the case with all other silicone compounds. In the instance of these compounds the cationic group is a water-soluble group.  Numerous silicone quats have been produced over the years (2-4). They differ in structure and properties. This article will look at a structure function relationship between the polymeric structure and their performance.


FORMULATOR TIP

The creation of new, cost effective formulations for hair care require the product to provide many attributes. These include consumer perceptible wet and dry comb attributes, softness, and antistatic properties. Because these properties are determined by the exact structure of the cationic silicone chosen and how it interacts in the formulations, formulators need to carefully and thoughtfully screen materials. This requires an understanding of the product under evaluation and specifically the understanding of how the structure affects the performance in a specific formulation.

Cationic Compounds (5)

The most common class of cationic is the quaternary compound, Commonly, called a “quat” in surfactant jargon for a quaternary ammonium compound. This class of compounds includes nitrogen-containing materials in which the nitrogen has four non-hydrogen atoms surrounding them. Quats by virtue of their hydrophobic group and their cationic charge are substantive to hair, skin and cell walls of bacteria. These substrates are fatty in nature and generally have a negative charge, the ...