Redispersible Polymer powder RDP/VAE, is a special emulsion spray drying powder made of ethylene and vinyl acetate copolymer, because of its high bonding ability and unique properties, such as: water resistance, construction and heat insulation, so, has a very wide range of applications.
what role of RDP can play in wall putty?
1, improve the adhesion and mechanical properties of wall putty. Redispersible Polymer powder RDP/VAE in contact with water can be quickly dispersed into emulsion, and has the same properties as the initial emulsion, that is, water evaporation can form a film, this film has high flexibility, high weather resistance and high adhesion to a variety of substrates.
2, improve the cohesion of wall putty, excellent alkali resistance, wear resistance, increase the flexural strength.
3, improve the water resistance and permeability of wall putty.
4, improve the water retention of wall putty, increase the opening time.
5, improve the impact resistance and enhance the durability of wall putty.
In wall putty can Redispersible polymer powder is a very important additive, generally speaking, the inner wall putty can be added or not. But in the exterior wall wall putty must be added in the dispersion of polymer powder , can be in the dispersion of polymer powder on the wall putty has good toughness and late strength, to prevent the occurrence of late powder and other problems.
Customers often ask questions about wall putty, such as wall putty easy to take off powder, powder serious, or strength is small and so on. All know do wall putty need to add cellulose ether, many users do not add redispersible polymer powder . Because it will increase the cost of wall putty, so in order to save cost, many customers do not add, this is why putty is easy to powder the key quality problem!
Cellulose ether can absorb moisture when it is expanded by water. The main role of cellulose is to retain water, but it will slowly RDP powder after a long period of time. This kind of putty is loose, water absorption rate is high, easy powder, no strength, no elasticity. To improve the putty above problems can adjust the putty formula, the appropriate addition of some dispersed polymer powder to improve the late strength of the wall putty.
Putty in the production process if you can add enough Redispersible polymer powder , or use low-grade putty special polymer powder , what impact will wall putty have ?
wall putty can be in Redispersible polymer powder RDP/VAE to add less, the most direct performance is putty layer loose, surface flour, poor leveling, it is difficult to form a dense film. This wall is prone to peeling, blistering, peeling, cracking and other phenomena. If the inferior wall putty is selected, the wall will produce harmful gases, such as formaldehyde and other human body damage is obvious.
Therefore, the premise of high quality wall putty production is to choose a good hydroxypropyl methyl cellulose HPMC and redispersible polymer powder RDP and other product additives to produce green products.