Sodium Carboxymethyl Cellulose(CMC) is a kind of Cellulose Ether hydrocolloid which is made from natural cellulose(refined cotton or wooden fiber). It’s a kind of excellent emulsifier and thickener that can be used in food, detergent, ceramic, painting, paper making, and mining industries etc.
There are many types of Sodium CMC based on different viscosity range, purity and D.S(Degree of Substitution) etc. How to distinguish different types of Sodium CMC and chose the most suitable type of CMC ? Let’s introduce some tips briefly here:
1. How to distinguish low viscosity CMC, medium viscosity CMC and high viscosity CMC ?
Normally, we test CMC viscosity in 1% or 2% solution with Brookfield viscometer. For Example:FH6000(1%soln.6000-7000mPa.s) viscosity is higher than FH3000(1%soln.3000-4000mPa.s), and FH100(1%soln.100-200mPa.s) is the low viscosity CMC among the three types of CMC.
So if we want to compare viscosity level, we must put the sample test in the same aqueous solution and check the viscosity value.
2. How Degree of Substitution(D.S) influence Sodium CMC performance ?
The flow ability of Sodium CMC is better with higher Degree. The solution is more transparent and whole liquid system is more stable. Normally, if the D.S is more than 0.9, it can be used in acid and salty foods. And if Sodium CMC is used in textile sizing application, the D.S(Degree of Substitution) should be more than 1.2 and purity more than 90%.
3. How to decide the purity level ?
Normally, there are various types of purity, like 55%, 65%, 75%, 85%, 95%, 98% and 99.5%. It all depends on your applications requests. Generally speaking, food Grade CMC, pharmaceutical grade CMC and cosmetic grade CMC require purity more than 99.5% and the other technical grade CMC require purity lower than 98%.
We here only introduced three main items(purity, viscosity and Degree of Substitution(D.S)) of CMC. If you have more questions about Sodium CMC, please contact SINOCMC freely.
SINOCMC Team