What is the Role of Redispersible Powder in Gypsum-based Mortar?

02 Jun.,2022

What is the role of redispersible powder in gypsum-based mortar? Answer: The role of dispersible polymer powder in wet gypsum slurry.

 

1. What is the role of redispersible powder in gypsum-based mortar?

 

Answer: The role of dispersible polymer powder in wet gypsum slurry:

 

① construction performance;

② flow performance;

③ Thixotropy and sag resistance;

④ improve cohesion;

⑤ Extend the opening hours;

⑥ Enhance water retention.

 

2.The role of dispersible polymer powder after gypsum curing:

 

①Increase tensile strength (additional adhesive in gypsum system);

②Increase the bending strength;

③ reduce the elastic modulus;

④ Improve deformability;

⑤Increase the material density;

⑥Increase wear resistance;

⑦ Improve cohesive strength;

⑧ Reduce material water absorption;

⑨ Make the material hydrophobic (add hydrophobic rubber powder).

 

3. What are the common gypsum binders?

 

Answer: Cellulose ether water-retaining agent can increase the bonding effect between gypsum and substrate. If you want to bond gypsum boards, gypsum blocks, gypsum decorative lines, etc., in addition to adding cellulose ether water-retaining agent, you need to add some organic adhesives , Generally use dispersible latex powder, polyvinyl alcohol powder, carboxymethyl cellulose (CMC), modified starch, polyvinyl acetate (white glue), vinyl acetate-ethylene copolymer emulsion, etc.

 

4.How to choose the adhesive for gypsum?

 

Answer: The water resistance of polyvinyl alcohol and carboxymethyl cellulose is poor, but because gypsum can only be used indoors as an adhesive, and the requirements for water resistance and durability are not high, so choose polyvinyl alcohol and carboxymethyl cellulose to increase the viscosity The knot is relatively economical. Polyvinyl acetate and vinyl acetate-ethylene copolymer emulsion have excellent adhesion, and have good waterproofness and durability, but the dosage is larger than that of polyvinyl alcohol, which generally accounts for more than 1.0% of the amount of gypsum. Prices are higher.

 

Semonova group will produce HPMC, MHEC, RDP, VAE and other cellulose ethers. If you have any request, please be free to contact us at any time.