MHK244 - Water Retention Hydroxypropyl Methyl Cellulose

Structural formula

Wherein, R stands for –H, -CH3 or –CH2CHOHCH3 and x for degree of polymerization

CAS

9004-65-3

Molecular Formula

[C6H7O2（OH）x-m-n（OCH3）m（OCH2CH（OH）CH3）n]x

Physico-chemical properties

Appearance                  White or off-white, odorless, tasteless;
Particle                         98.5% through 100 mesh ,100% through 80 mesh ;
Stacking Density          0.25-0.70 (g·cm-3)
Solubility                      It is soluble in water and some organic solvent, like ethyl alcohol /water, acetone /water, methyl chloride etc.The solution with surface activity, will not be effected by pH value in water.

Typical viscosity range of HuaMao® HPMC products with NDJ-1 rotary viscometer at 20℃ with 2% solution.

Type	Typical viscosity
040	3-9
067	10-20
079	20-30
096	40-60
114	80-120
148	300-800
153	400-600
165	700-900
180	1200-2000
205	3500-5500
222	7000-9000
227	9000-11000
237	13000-17000
244	18000-22000
261	35000-45000
271	55000-65000
277	65000-85000
284	85000-130000
294	130000-180000
301	180000-230000
307	＞230000

*The above specifications have grade that disperses in cold water, such as MHE 227S, "S" stands for dispersing in cold water

Physico-chemical properties of MHK244

Item	Required Specifications	Test Result
Appearance	White free-flowing power	White free-flowing power
Hydroxypropoxy(WT%)	4.0-12	9.5
Methoxy(WT%)	19-24	21.93
Gel Temperature (℃)	70-90	71.5-73.0
Ash Content (%)	≤5	4.63
Moisture Content (%)	≤5	3.59
PH	5.0-8.0	7.64
Partical Size	Mesh 80	100% through
Viscosity (NDJ-1)	85000-100000	89000
Viscosity (Brookfield)	45000

2 % solution; on dry basis,20℃

Precautions for confecting Solution

1. when adding the product and after adding, should be fully stirred to achieve the highest viscosity.
2. the preparation of dissolved concentration, according to the viscosity of the product determined low viscosity products (viscosity less than 4000) can be equipped with 10-15% concentration, high viscosity products (viscosity is greater than 30000) the largest preparation of 2-3%.

Customization
HuaMao® can customize according to customer demand, production of goods.
1. HuaMao® can customize the packaging according to the customer's requirements.
2. HuaMao® can produce HPMC which is the special technical index, according to the customer's demand.

The water retention of mortar is an important index to measure the stability of the internal components of new cement mortar. Adding the amount of cellulose ether can improve the water retention of mortar. In order to make the cementitious material fully hydrated, the reasonable amount of cellulose ether can keep the moisture in the mortar for a long time and ensure the hydration reaction of the cementitious material is fully carried out.

In the cement mortar and gypsum base slurry, the main water retention and thickening effect of HPMC can effectively improve the bond strength and sag resistance of the slurry.

Air temperature, temperature and wind pressure can affect the moisture content of cement mortar and gypsum based products. Therefore, in different seasons, adding HPMC the same amount of product water conservation effect there are some differences. In the concrete construction, we can adjust the water retention effect of the slurry by adding and subtracting the amount of HPMC. The water retention of HPMC under the high-temperature condition is an important index to distinguish the quality of HPMC. Excellent HPMC products can effectively solve the problem of water conservation under high temperature. High-quality HPMC is needed to improve the water retention of the slurry in the high-temperature season, especially in the hot and dry areas and the thin layer construction of the Xiangyang surface. High-quality hpmc with very good uniformity, its methoxy and hydroxypropyl chi groups are evenly distributed along the chain of cellulose molecules, can improve the hydroxyl and ether bond oxygen atom and water association to form hydrogen bonding capacity, so that free water into a combination of water, so as to effectively control the high temperature caused by the evaporation of water, to achieve high moisture retention.

High-quality cellulose hpmc can be evenly and effectively dispersed in cement mortar and gypsum-based products, and wrap all the solid particles, and form a layer of wetting film, the water in the base is gradually released over a long period of time, and inorganic cementitious material hydration reaction, thus ensuring the bonding strength and compressive strength of the material. Therefore, in the high temperature in the summer construction, in order to achieve water conservation effect, the need to add high quality of HPMC products in accordance with the formula, otherwise, will appear dry too fast and caused by insufficient hydration, strength reduction, cracking, hollowing and shedding quality problems, but also increase the difficulty of construction workers. As the temperature decreases, the added amount of HPMC can be reduced gradually, and the same water retention effect can be achieved.