Characteristics of Cellulose ethers
(1). Product Status: powdery or granular.
(2). State of Charge: non-ionic state and anionic state
Cellulose ethers in non-ionic state have compatibility with aqueous solutions of other additives, including:
1) Methyl cellulose (MC)
2) Hydroxy ethyl methyl cellulose (HEMC)
3) Hydroxy propyl methyl cellulose (HPMC)
4) Hydroxy ethyl cellulose (HEC)
5) Anionic state: Carboxymethyl cellulose is unstable in the case of calcium ions.
6) Sodium Carboxymethyl cellulose (Na-CMC)
(3). PH Value: typically between 3.0 and 11.0; the solubility of cellulose ether is affected by the acidic and alkaline. When the PH value is in acidic media conditions, the cellulose ether dissolves very slowly; while in alkaline media conditions, it dissolves rapidly.
Methyl cellulose (MC) can be soluble in water but insoluble in hot water and can form flocs at the temperature of 45-60℃. Hydroxy ethyl methyl cellulose (HEMC) can be soluble in water but insoluble in hot water and can form flocs at the temperature of 45-60℃. After cooling, it will disappear. Anionic carboxyl cellulose can be soluble in water at any temperature. The dissolution time is related to the temperature and the product status. The dissolution will speed up at elevated temperatures.
(5). Thickening Properties
It is well known that mortar requires a certain consistency. In a certain period of time, maintaining good stability of consistency helps to improve adhesion properties and sag resistance. Usually water is added to mortar to obtain a suitable consistency, and the amount of water needed depends on components and the proportion of ingredients. Cellulose ethers are the main factors affecting the water demand, especially the viscosity of the cellulose ethers, mixing proportion and other factors. Cellulose ethers dissolve in water in the morphology of colloids and polymers. Level of viscosity is determined by the degree of polymerization of cellulose ethers. Due to the differences of degree of polymerization, or molecular weight and the concentration, the performance characteristics of consistency are also different, and the consistency of the solution will increase with the increase of degree of polymerization and the concentration.
(6). Water Retention Properties
The cellulose ether has the performance of reducing moisture loss, delays the absorption of water by the porous materials, and is conducive to cement hydration and longer opening hours. In the joint action of water retention and consistency, it promotes the adhesion and strength of the mortar. The greater the amount, the concentration, and the viscosity of cellulose ether are, the higher the water retention will be.
1. It is rich in raw material resources and renewable. The raw materials of cellulose ethers are natural celluloses, and are the most abundant natural organic renewable resources on earth. There are billions of tons of renewable plant celluloses by photosynthesis only annually.
2. It is biodegradable and non-toxic, with low calorie and good biocompatibility. Most of cellulose ethers are environmentally friendly, nontoxic and harmless to the human and animals, and can be used in food, medicine, cosmetics and other industries.
3. Its products have wide applications. As an important water-soluble polymer, the cellulose ether is applied in fields involving oil exploration, ceramics, washing powder, food, medicine, cosmetics, printing, building materials, paper, textile, paint, leather, high polymer, aerospace and defense.
4. The product is rich; the performance is diverse and the output is large. There are many kinds of cellulose ethers. Currently, dozens of cellulose ethers can be synthesized. There are more than ten kinds of cellulose ethers with large-scale production conditions. The most commonly used products are CMC, HPMC, HEC and MCC. The cellulose ether has a large output. Over the whole world, it has a total annual production capacity of 80 million tons, of which non-ionic cellulose ether accounts for about 20 million tons, while ionic cellulose ether accounts for over 60 tons, and is still growing.