The name Carbopol 940 may be unfamiliar to non professionals, but it is an indispensable and important component in the cosmetics and pharmaceutical industry. As a polymer cross-linked with acrylic acid, propylene sucrose, or propylene pentaerythritol, carbomer 940 plays a crucial role in the production of cosmetics and pharmaceuticals due to its unique properties.
The Carbopol 940, originally produced by Goodrich Corporation in the United States under the trade name Carbopol, appears as a white loose powder that is not only hygroscopic but also has a unique slight odor. This polymer is easily soluble in water, ethanol, and glycerol, thanks to its high carboxyl content of 56% -58% in its molecules, which gives it a weakly acidic characteristic. Due to these unique properties, Carbopol 940 is widely used in the pharmaceutical field, especially in cosmetics, where it is an excellent medicinal adjuvant.
In drug production, the functions of Carbopol 940 are diverse. It can be used as a thickener to provide a stable texture for drugs; As an adhesive, ensuring a tight bonding of pharmaceutical ingredients; As the matrix of gel, it provides suitable forms for drugs; It can also serve as a matrix material for suspension matrices and drug controlled release formulations, ensuring effective drug release in vivo. Among numerous models, the Carbopol 940 has become the most popular due to its excellent performance and wide range of applications.
However, people often encounter various problems in the process of preparing Carbomer 940 gel. One of the most common problems is the production of a large number of foam. Faced with this issue, many people may consider adding defoamers to solve the problem, but we must carefully choose a solution from the perspective of drug safety. After all, we cannot ignore the consideration of drug safety just because we pursue temporary convenience.
We can use the following two methods to address this issue:
Firstly, the pre soaking method. 24 hours before actual production, dissolve carbomer in deionized water according to production requirements. At this point, we don't need to stir, we just need to let Capom naturally absorb water. When there is no white powder or white solution on the surface, it indicates that Capom has fully absorbed water. At this point, we can mix the aggregates and add a neutralizing agent to adjust the pH value to around 7, achieving a thickened state. Finally, use a disperser to stir at low speed to ensure the uniformity of gel.
Secondly, the homogenizer method. We can add carbomer to the homogenizer according to the actual production ratio for homogenization. During the homogenization process, we need to ensure that white spherical objects are not visible. Then, neutralizer is added and waiting for the gel to form. Finally, vacuum emulsifier is used to exhaust the air in gel to ensure the purity of gel.
In addition to the foam problem, another common problem is the flocculation and transparency reduction of gel. This is usually caused by the addition of strong hydrophilic non electrolytes such as ethanol. To solve this problem, we can try slowly adding purified water to the finished rubber and stirring it. This method can to some extent improve the appearance transparency of the finished product.
Finally, Desheng would like to remind everyone that the dispersion time of Capom 940 in water is influenced by water temperature and quality. To ensure the stability of the product, it is recommended to use deionized water for dissolution. Meanwhile, it takes longer to dissolve in organic solutes. Generally speaking, the soaking time of Capom 940 is about 8 hours, but the specific dissolution time also depends on the amount of dissolution. Therefore, in practical operation, we need to make adjustments according to specific situations.
