The Performance characteristics，Application field，Physicochemical index，adhesive strengthening role of Redispersible emulsion powder
Redispersible latex powder products for water-soluble redispersible powder, divided into ethylene/vinyl acetate copolymer, vinyl acetate/tertiary vinyl carbonate copolymer, acrylic copolymer, etc., spray drying made of powder adhesive, with polyvinyl alcohol as a protective colloid. This powder can be quickly dispersed into emulsions after contact with water, because the redispersible emulsion powder has high bonding ability and unique properties, such as: water resistance, construction and heat insulation, so their application range is extremely wide
Development history
The research of redispersible polymer powder began in 1934 with the polyvinyl acetate redispersible latex powder of I.G.Fobenindus AC in Germany and the powder latex in Japan. After World War II, the serious lack of labor and construction resources forced Europe, especially Germany, to use a variety of powder building materials to improve construction efficiency, in the late 1950s, Germany’s Hearst Company and WACKER chemical company began the industrial production of redispersible emulsion powder. At that time, the redispersible emulsion powder was also mainly polyvinyl acetate type, which was mainly used for woodworking glue, wall primer and cement wall material. However, due to the limitations of PVAc adhesive powder, such as high minimum film forming temperature, poor water resistance and poor alkaline resistance, its use is greatly limited.
With the success of the industrialization of VAE emulsions and VA/VeoVa emulsions, redispersible emulsion powders with a minimum film forming temperature of 0℃ and good water resistance and alkaline resistance were developed in the 1960s, and then their application was widely promoted in Europe. The scope of use has gradually expanded to a variety of structural and non-structural building adhesives, dry mix mortar modification, wall insulation and finishing systems, wall smoothing glue and sealing plaster, powder coatings, building putty fields.
Performance characteristics
It has a very outstanding bond strength, improves the flexibility of mortar and has a long opening time, gives mortar excellent alkali resistance, improves mortar adhesion, folding strength, water resistance, plasticity, wear resistance and workability, and has a strong flexibility in the flexible anti-cracking mortar.
Application field
Tile binder
External wall insulation system bonding mortar
External wall insulation system plastering mortar
Tile pointing agent
Free-flowing cement mortar
Flexible putty for interior and exterior walls
Flexible anti-cracking mortar
Rubber powder polystyrene particle insulation mortar
Dry powder coating
Polymer mortar products with higher requirements for flexibility
Physicochemical index
|
Performance |
index |
|
Appearance |
white powder, free flow |
|
Solid content（wt%） |
≥98.0 |
|
Ash content（wt%） |
10±2% |
|
Packing density（g/L） |
300-500 |
|
Protective colloidal |
polyvinyl alcohol |
|
Particle size |
≤4% greater than400um |
|
PH |
6-8 |
|
glass transition temperature Tg(DSC)℃ |
variable |
|
MFFT（℃） |
0～5℃ |
It is recommended to store in a cool and dry place for six months, please use as early as possible in summer, if stored in a hot and humid place, it will increase the chance of caking, and please use as much as possible after opening the bag, otherwise it is necessary to seal the bag mouth to avoid absorbing moisture from the air. International standard paper-plastic composite square bottom valve pocket, 20 ~ 25kg/ bag.
Redispersible emulsion powder can be dispersed to form film and play a strengthening role as a second adhesive.
* Protect the colloid is absorbed by the mortar system (it will not be destroyed by water after film formation, or “secondary dispersion”;
* The film-forming polymer resin is distributed throughout the mortar system as a reinforcing material, thereby increasing the cohesion of the mortar; Improve tensile strength; Increase bending strength; Reduce the elastic modulus; Improve deformability; Increase the density of the material; Increase wear resistance; Improve cohesion strength; Reduce the carbonization depth; Reduce material water absorption; Make the material have excellent water increase (add Hydrophobic redispersible polymer powder).
It has outstanding waterproof performance, good bond strength, can also increase the elasticity of mortar and have a long opening time, and give mortar excellent alkali resistance, can improve the mortar adhesion/adhesion, bending strength, wear resistance and constructability, in the flexible crack mortar has a stronger flexibility.
The role of redispersible latex powder in putty powder: strong adhesion and mechanical properties, outstanding water resistance, permeability, and excellent alkali resistance, wear resistance, and can improve water retention, increase opening time, enhance durability
1.the role of newly mixed mortar
(1) Improve the constructability.
(2) Add additional water retention to improve cement hydration.
(3) Increase workability.
(4) Avoid early cracking.
2.the role of hardening mortar
(1) Reduce the elastic modulus of mortar and increase the matching of the base.
(2) Increase flexibility and anti-cracking.
(3) Improve powder resistance.
(4) hydrophobic or reduced water absorption.
(5) Increase the adhesion to the base.
1.Stronger adhesion and mechanical properties
2.improve cohesion, excellent resistance, enhance flexural strength
3.Highlight water resistance and permeability
4.excellent alkaline resistance, wear resistance
5.improve water retention, increase opening time, improve workability
6.improve impact resistance, enhance durability
