Introduction:
Carbomer 940, CAS 9003-01-4, also known as carbomer 940, is a kind of high molecular polymer cross-linked by acrylic acid and acryloyl sucrose or acryloyl pentaerythritol. It is a white loose powder with characteristic slight odor and strong hygroscopicity. Its average water content is 8%. Carbomer resin exists in water in the form of acid. It is easy to swell in water and polar organic solvents (such as ethanol, glycerin, etc.) Characteristics of colloidal solution. Because of 56% - 68% carboxylic acid group in the molecule, these resins are weakly acidic. Although they are weaker than acetic acid, they can easily react with inorganic bases and organic bases to form salts.
Because of its swelling and weak acidity, it is a very important rheologic regulator. The neutralized Kabo resin is an excellent gel matrix with thickening, suspension and other important properties. It has high transparency, high viscosity, strong suspension ability, very short rheology and thixotropy, low ionic shear resistance, simple process and good stability. It is widely used in shampoo, shower gel and bath. Cream, cream and other cream products are especially suitable for transparent products. The most important point is that carbomer 940 is mild and not irritant to skin.
matters needing attention:
1. PH value: the best pH value range of Carbopol 940 is 4-10, higher or lower than this range will lead to changes in the viscosity of the system.
2. The components in the formula that are not easy to be compatible: protein, PVP resin, polyethylene glycol (PEG), polyethoxylated surfactant will interact with the non neutralized Carbopol 940, and it is necessary to partially neutralize Carbopol 940 before adding.
3. The presence of electrolyte will reduce the thickening efficiency of Carbopol resin: Carbopol 940 is sensitive to salt and cation, when the concentration of soluble ion in the component is greater than 0.1%, the dosage of the component should be reduced appropriately.
Deionized water can be used as the matrix of the main material, and salt can be added after neutralization to master the influence of salt on the system. High valence ions (CA, Mg, Fe, AI) will cause serious damage to the system and should be removed. The Fe and Cu converted in the production process will reduce the viscosity of the system and lead to the instability of the system. Stainless steel or non-metallic equipment can be used to prepare products to avoid such effects. In addition, adding EDTA to chelate metal ions can also achieve good results. In addition to the above methods, the appropriate model of Carbopol 940 (such as Carbopol 940l342ge resin) can also be selected, which has low sensitivity to soluble salts.
4, insoluble matter: when there are insoluble components, carbo 940 system is difficult to present clear and transparent gel, and solubilization technology can reduce or eliminate this effect.
5. High shear agitation and pump delivery: carbo 940 is thickened by forming a gel skeleton. After Carbopol neutralization, high shear stirring, long-term stirring, grinding or pump chipping will damage its skeleton and cause viscosity loss, so pipeline homogenizer should be used. Use low shear pumping, such as reciprocating diaphragm pump or gear pump.
6. Long term UV irradiation can reduce the viscosity of carbomer resin.
7. Packing: it can be sealed with moisture-proof and airtight plastic bags, and then packed in cardboard boxes. Carbomer 940 has strong hygroscopicity. During storage, attention must be paid to sealing, and care must be taken to avoid moisture absorption and caking in the exposed air. If there is slight caking, it can become loose powder by gently patting and pressing, which will not affect the thickening effect. After use, it is better to put it in a sealed container with desiccant.
8. Transportation: carbomer is polyelectrolyte, sometimes static when rubbing or extruding resin particles. In case of splashing, remove the dry powder with a broom first. Do not rinse with water. Otherwise, it will form very slippery gel on the ground or equipment.
Hubei xindesheng company specializes in providing carbomer 940, 980 products and after-sales technical support. If you have any questions, please call for details.
