CAS No 9003-01-4 Carbopol 940 980 In Lotions Creams Gels

CAS No 9003-01-4 Carbopol 940 980 In Lotions Creams Gels

1 Introduction

Carbomer polymer(synonym: Carpobol), chemical name: Carboxypolymethylene. It is high molecular weight cross-linked polymer.is a generic name for synthetic high molecular weight polymers of acrylic acid used as thickening,dispersing,suspending and emulsifying agents in pharmaceuticals and cosmetics.

2. Thickening mechanism

2.1 Neutralization (salt formation) thickening

Usually, the acidic carbomer resin 940 is neutralized to form a salt, so that the curled resin molecules expand due to the electric repulsion force and cause thickening. Sodium hydroxide, potassium sodium hydroxide and triethanolamine are commonly used neutralizers, so carbomer Sensitive to ions.

2.2 Hydrogen bond thickening

Carbomer molecules as carboxyl donors can combine with one or more hydroxyl groups to form hydrogen bonds and thicken. This neutralization method takes time. Commonly used hydroxyl donors are non-ionic surfactants and polyols. This method takes time, from 5 minutes to several hours, for the consistency to reach the highest value. The PH value of this kind of material is slightly acidic, and the dispersion can be heated to 70°C (but should not exceed) to speed up the thickening.

3. Roles and uses

Carbomer 940 has the characteristics of short rheology, high viscosity, high clarity, low ion resistance and shear resistance. Its role in the product is mainly reflected in three aspects: thickening, suspension and emulsification. Carbomer 940 can produce high viscosity when the content is very low (normal dosage is 0.25-0.5%). Carbo resin can be used as an excellent suspending agent to permanently suspend insoluble components in the system; it can also be used as an emulsifier, emulsifying and stabilizing in the oil/water phase. In addition, it is also a transparent base and medicinal excipient base for high-end cosmetics, and it is also the most effective water-soluble thickener.

4. Technical indicators

Brand: Carbomer 940

Appearance: loose white powder, slightly acidic

pH value (0.5% aqueous solution) :2.7-3.5

Viscosity (in 0.5% aqueous solution) :50,000-65,000

Apparent density :0.21g/cm3

Specific gravity: 1.41

Equivalent :76±4

Moisture :content up to 2.0%

Ash content (average): 0.009ppm

Balanced water content (when relative humidity is 50%): 8-10%

Glass transition temperature :100-105℃

Carboxyl :56%～68%

5. Matters needing attention

5.1 After carbomer is neutralized, long-term stirring or high-shear stirring will cause viscosity loss

5.2 The presence of electrolyte will reduce the thickening efficiency of carbo resin

5.3 Long-term ultraviolet radiation will reduce the viscosity of carbomer resin.