In recent years, a lot of resin polymer powder, high-strength water-resistant polymer powder and other very cheap polymer powder have appeared on the market to replace the traditional VAE emulsion (vinyl acetate-ethylene copolymer), which is spray-dried and made of recyclable polymer powder. Dispersed polymer powder, so what is the difference between resin powder and redispersible polymer powder, can resin powder replace redispersible polymer powder? Mortar Technology Center will lead you to briefly analyze the difference between the two for your reference:
(1), redispersible polymer powder
At present, the redispersible polymer powders widely used in the world are: vinyl acetate and ethylene copolymer powder (VAC/E), ethylene, vinyl chloride and vinyl laurate ternary copolymer powder (E/VC/VL), acetic acid Vinyl ester, ethylene and higher fatty acid vinyl ester ternary copolymer powder (VAC/E/VeoVa), these three redispersible polymer powders dominate the entire market, especially vinyl acetate and ethylene copolymer powder VAC/E E, occupies a leading position in the global field and represents the technical characteristics of redispersible polymer powder. Still the best technical solution in terms of technical experience with polymers applied to mortar modification:
1. It is one of the most used polymers in the world;
2. The application experience in the field of construction is the most;
3. It can meet the rheological properties required by the mortar (that is, the required constructability);
4. The polymer resin with other monomers has the characteristics of low organic volatile matter (VOC) and low irritating gas;
5. It has the characteristics of excellent UV resistance, good heat resistance and long-term stability;
6. High resistance to saponification;
7. It has the widest glass transition temperature range (Tg);
8. It has relatively excellent comprehensive bonding, flexibility and mechanical properties;
9. Have the longest experience in chemical production of how to produce stable quality products and experience in maintaining storage stability;
10. It is very easy to combine with the protective colloid (polyvinyl alcohol) with high performance.
(2), resin powder
Most of the “resin” polymer powder on the market contains the chemical substance DBP. You can check the harmfulness of this chemical substance, which affects male sexual function. A large amount of this kind of polymer powder is piled up in the warehouse and in the laboratory, and it has certain volatility. In the Beijing market, which is famous for its abundance of “polymer powder”, there is now a “polymer powder” soaked in solvents with various names: high-strength water-resistant polymer powder, resin polymer powder, etc. Typical features:
1. Poor dispersibility, some feel wet, some feel flocculent (it should be a porous material like sepiolite), some are white and slightly dry but still smell bad;
2. It smells very pungent;
3. Some colors have been added, and the colors currently appearing are white, yellow, gray, black, red, etc.;
4. The amount of addition is very small, and the amount of addition for one ton is 5-12 kg;
5. The early strength is surprisingly good. The cement has no strength in three days, and the insulation board can be corroded and stuck;
6. It is said that the XPS board does not need an interface agent.
Through the samples obtained so far, it can be concluded that it is a solvent-based resin adsorbed by light porous materials, but the supplier wants to deliberately avoid the word “solvent”, so it is called “polymer powder”.
shortcoming:
1. The weather resistance of the solvent is a big problem. In the sun, it will evaporate in a short time. Even if it is not in the sun, the bonding interface will decompose faster because of the cavity construction;
2. Aging resistance, solvents are not temperature resistant, everyone knows this;
3. Since the bonding mechanism is to dissolve the interface of the insulation board, on the contrary, it also destroys the bonding interface. If there is a problem with this problem in the later stage, the impact will be fatal;
4. There is no precedent of application in foreign countries. With the mature basic chemical experience abroad, it is impossible not to discover this material.
summary:
Redispersible polymer powder:
1. The redispersible polymer powder product is a water-soluble redispersible powder, which is a copolymer of ethylene and vinyl acetate, with polyvinyl alcohol as a protective colloid.
2. VAE redispersible polymer powder has film-forming properties, 50% aqueous solution forms an emulsion, and forms a plastic-like film after being placed on the glass for 24 hours.
3. The formed film has certain flexibility and water resistance. It can reach the national standard.
4. Redispersible polymer powder has high performance: it has high bonding ability, unique performance and outstanding waterproof performance, good bonding strength, endows mortar with excellent alkali resistance, and can improve the adhesion and flexural strength of mortar In addition to plasticity, wear resistance and construction, it has stronger flexibility in anti-cracking mortar.
Resin powder:
1. Resin polymer powder is a new type of product modifier for polymer, resin, high molecular polymer, and finely ground polymer powder.
2. Resin polymer powder has general durability, wear resistance, poor dispersion, some feel flocculent (it should be a porous material like sepiolite), and there are white powders (but have a pungent smell similar to kerosene ).
3. Some resin powders are corrosive to the board, and waterproofing is not ideal.
4. The weather resistance and water resistance of resin polymer powder are lower than those of polymer powder. Weather resistance is a big problem. In the sun, it will evaporate in a short time. Even if it is not in the sun, the bonding interface will Because it is a cavity construction, it will also decompose faster.
5. Resin polymer powder does not have moldability, let alone flexibility. According to the testing standards for external wall insulation mortar, only the damage rate of polystyrene board meets the standard. Other indicators are not up to standard.
6. Resin polymer powder can only be used for bonding polystyrene boards, and cannot be used for bonding vitrified beads and fireproof boards.
Post time: Feb-02-2023