Background and overview

Carbomer, as an efficient thickening agent, suspending agent and gel matrix, has been widely used in cosmetics. Carbomer 900 series are polymer copolymers of acrylic acid and allyl sucrose or allyl pentaerythritol. According to the relative molecular weight and crosslinking degree of polymers, Carbomer can be divided into many different types. Carbomer 980 is one of carbomer series products.

Carbomer powder and gel

Related research:

The rheological properties and influencing factors of carbomer 980 were studied. The rheological properties of carbomer 980 were affected by various factors such as neutralization type, pH value, concentration, electrolyte and so on. The neutralization properties of carbomer 980 in different neutralization bases were different. Among them, Na0H neutralization carbomer 980 could change the viscosity of the gel in the neutralization process.

The viscosity of carbomer 980 gel is positively correlated with the concentration. The higher the concentration, the higher the viscosity of the gel. The initial pH value of Carbopol 98 with different concentrations before neutralization is different. The higher the concentration is, the lower the initial pH value is.

Carbomer 980 gel is sensitive to electrolyte ions. The presence of electrolyte makes the viscosity of carbomer 980 gel drop sharply, and the two valence ion has greater influence than monovalent ion. The decrease of viscosity of carbomer gel is mainly due to the reduction of the repulsive force of isoelectric charges on the main chain of polymer, thus reducing the actual effective concentration of carbomer in the system.

Different ions have different effects on the viscosity of carbomer gel, which is mainly related to the number of total charges of ions in the solution. The monovalent ions weaken the viscosity of carbomer gel by shielding the charge, resulting in the decrease of the viscosity of carbomer gel. Besides the action of the two valence ion, when the concentration is enough, it will precipitate with carbomer to form a salt substance, which will further affect the gel. The viscosity and transparency of the product.

The effect of 5 different electrolyte ions on the viscosity, pH value and turbidity of carbomer 980 gel was found to be basically the same. The results showed that the electrolyte had a certain correlation with the viscosity, pH value and turbidity of carbomer.

In this study, the rheological properties and influencing factors of carbomer 980 were studied. Because the viscosity of many cosmetics may affect the sensory characteristics of products, which directly affects the acceptance of products by consumers, how to control these rheological parameters becomes a decisive factor in the practical application of cosmetics formula. Different carbomer and appropriate concentration should be selected according to the actual demand of the formula, and the influence of various factors on carbomer system should be considered comprehensively.