Hand Washing Gel Raw Material Carbomer carbopol 940 CAS 9003-01-4 White Powder

Hand-washing gel raw material Carbomer 940,CAS 9003-01-4,white powder

1 Introduction

Carbomer, English name: Carbomer 940, CAS No. 9003-01-4, appearance is white loose powder, slightly odor, strong hygroscopicity; It is acrylic cross-linked resin obtained by cross-linking pentaerythritol and acrylic acid, carbomer Resin exists in water in an acidic form, and is easy to swell in water and polar organic solvents (such as ethanol, glycerin, etc.). It contains polyalkenyl polyether cross-linked acrylic polymer with 56%—68% carboxylic acid groups in the molecule, which makes these resins weakly acidic. Although weaker than acetic acid, it is very easy to interact with inorganic alkalis and organic alkalis. The reaction produces salts. Because of its swelling and weak acidity, it is a very important rheology modifier. The neutralized carbomer is an excellent gel matrix with important properties such as thickening and suspension, simple process and good stability. Carbomer 940 is safe and non-toxic to the skin, so it is widely used in lotions, creams, gels, cosmetics, and is especially suitable for transparent products.

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.

6. Packaging and storage

The carbomer produced by Desheng is packed in a non-toxic polypropylene plastic bag, which is moisture-proof and air-tight, and then packed in a cardboard drum, 25kg/drum. Carbomer has strong moisture absorption, so you must pay attention to sealing when storing, and be careful not to absorb moisture and agglomerate in the air. If there is a slight agglomeration, pat it gently, it will become a loose powder and will not affect the increase. For thickening effect, once the product is started, it is best to place it in a sealed container with desiccant.