Views: 2 Author: Site Editor Publish Time: 2022-09-14 Origin: Site
Hydroxypropyl methyl cellulose (HPMC) with no S, what is the difference?
1. HPMC is divided into instant type and rapid dispersion type
HPMC rapid dispersion with the letter S suffix, the production process, to add glyoxal treatment.
HPMC instant type does not add any letters, such as "100000" is "100000 viscosity fast dispersing HPMC".
2. With or without S, different characteristics
Fast dispersing HPMC, in cold water quickly dispersed, disappeared in the water, at this time the liquid has no viscosity, because HPMC is just dispersed in the water, no real dissolution, about two minutes later, the viscosity of the liquid slowly becomes large, forming a transparent viscous colloid.
Instant HPMC, can be rapidly dispersed in hot water at about 70℃, to be dropped to a certain temperature, viscosity slowly appears, until the formation of a transparent viscous colloid.
3. With or without S, different uses
Instant HPMC can only be used in putty powder and mortar, in liquid glue and paint and washing supplies, there will be a group phenomenon, can not be used.
Fast DISPERSIVE HPMC, application range is very WIDE, IN putty powder, mortar, liquid glue, paint, washing supplies can be used, there is no taboo.
1. Take the required amount of hot water and heat it to 80℃ or above in the container. Add this product gradually under slow stirring.
2, or heat 1/3 or 2/3 of the hot water to more than 85℃, add cellulose, get hot water slurry, then add the remaining amount of cold water, keep stirring, cooling the mixture is formed.
3, the number of cellulose mesh is fine, in the mixing powder is a separate small particle, after water is rapidly dissolved, the formation of the required viscosity.
4. Add cellulose slowly and evenly at room temperature, stirring continuously in the process until a transparent solution is formed.
What factors affect the water retention of hydroxypropyl methyl cellulose?
Hydroxypropyl methylcellulose HPMC products themselves water retention is often affected by the following factors:
1. HPMC homogeneity of cellulose ether
HPMC of uniform reaction, methoxy, hydroxypropoxy uniform distribution, high water retention rate.
2. Cellulose ether HPMC hot gel temperature
The hot gel has high temperature and high water retention rate. On the contrary, the water retention rate is low.
3. HPMC viscosity of cellulose ether
When the viscosity of HPMC increases, the water retention rate also increases. When the viscosity reaches a certain degree, the increase of water retention rate tends to be flat.
The amount of cellulose ether HPMC added
The greater the amount of cellulose ether HPMC added, the higher the water retention rate, the better the water retention effect.
In the range of 0.25-0.6%, the water retention rate increased rapidly with the increase of the addition amount. The increasing trend of water retention rate slowed down when the addition amount was further increased.