Carbomer 940 is a high molecular weight polyacrylic acid polymer commonly used in the formulation of gels, creams, and lotions, particularly in cosmetics, pharmaceuticals, and personal care products. It functions as a thickening agent, emulsifier, and stabilizer. Below are general materials and methods typically involved in working with Carbomer 940.
Materials of Carbomer 940:
1.Carbomer 940
- A type of polyacrylic acid that is crosslinked with allyl ethers of sugar.
2.Water (Distilled or Deionized)
- Usually the main solvent for Carbomer 940. It helps to dissolve or disperse the Carbomer.
- Neutralizing Agent (e.g., Triethanolamine, Sodium Hydroxide, or Potassium Hydroxide)
- Carbomer 940 is an acidic polymer, so it needs to be neutralized to form a gel. The neutralizing agent is used to raise the pH and activate the thickening process.
3.Preservatives (Optional)
- Depending on the formulation, preservatives such as phenoxyethanol, ethylhexylglycerin, or others might be included to prevent microbial growth.
4.Glycerin or Other Humectants (Optional)
- To enhance the moisturization properties of the final product.
5.Active Ingredients (Optional)
- Depending on the purpose of the formulation, active ingredients like vitamins, extracts, or medications can be incorporated.
6.Solvents (Optional)
- If needed, solvents like alcohol or propylene glycol may be used depending on the formulation type.
Methods of Carbomer 940:
1.Preparation of Carbomer Gel:
- Phase 1 (Water Phase):
Start by preparing the water phase. If using water-based ingredients or active components, they can be mixed into deionized or distilled water.
- Carbomer Dispersion:
Gradually sprinkle Carbomer 940 into the water while stirring gently to avoid clumping. Carbomer should be dispersed slowly into the water to form a smooth, uniform dispersion. Use a high-shear mixer or magnetic stirring to ensure thorough incorporation. Let it hydrate for about 30 minutes to ensure complete dispersion.
2.Neutralization of Carbomer 940:
- Slowly add the neutralizing agent (e.g., Triethanolamine or Sodium Hydroxide solution) to the Carbomer dispersion while continuously stirring.
- The neutralizer increases the pH of the system, causing the Carbomer to swell and thicken. The final pH should typically be between 6 and 7. Adjust the pH using a pH meter to ensure proper neutralization. This is a critical step for achieving the desired gel consistency.
3.Addition of Other Ingredients:
- After neutralization, other ingredients like humectants (glycerin, propylene glycol), preservatives, or active compounds can be added.
- Incorporate them carefully to avoid compromising the structure of the gel.
4.Final Mixing and Homogenization:
- Continue mixing the formulation until the gel reaches a smooth, homogeneous consistency.
- If necessary, use a homogenizer or high-shear mixer to break up any larger particles and improve the texture.
5.Final pH Check:
- Perform a final pH check to ensure it falls within the desired range (typically between 6 and 7). Adjust with a small amount of neutralizer if needed.
6.Packaging:
- Once the desired consistency is reached, the gel can be packaged into containers. Ensure that the product is kept in airtight containers to maintain its integrity and shelf life.
Important Notes:
- Viscosity Control:
The viscosity of Carbomer 940 gels is influenced by the pH and the level of neutralization. Over-neutralization can lead to thinning, while under-neutralization can result in a gel that is too weak.
- Water Quality:
Using deionized or distilled water is crucial because tap water may contain ions that could interfere with the thickening process.
- Storage:
Carbomer gels should be stored at room temperature, away from direct sunlight, to avoid degradation.
Example Formula:
1.Water Phase:
- Deionized Water – 80-90%
- Glycerin – 2-5% (optional)
2.Thickening Agent:
- Carbomer 940 – 0.5-2%
3.Neutralizer:
- Triethanolamine (TEA) – 0.5-2%
4.Preservative:
- Phenoxyethanol – 0.5%
5.Active Ingredients:
- Any specific active ingredients depending on the formulation (e.g., aloe vera, vitamin E, or medicated actives).
By following these general guidelines, you can create a stable, high-quality gel or cream using Carbomer 940.