In recent years, a lot of resin rubber powder, high-strength water-resistant redispersible polymer powder and other very cheap rubber powder have appeared on the market to replace the traditional VAE emulsion (vinyl acetate-ethylene copolymer), which is spray-dried and recyclable. Dispersible latex powder, then what is the difference between resin rubber powder and redispersible latex powder, can resin rubber powder replace redispersible latex powder?
1. Redispersible polymer powder RDP
At present, the widely used dispersible polymer powders in the world are: vinyl acetate and ethylene copolymer rubber powder (VAC/E), ethylene and vinyl chloride and vinyl laurate terpolymer rubber powder (E/VC/VL), acetic acid Vinyl ester and ethylene and higher fatty acid vinyl ester terpolymer rubber powder (VAC/E/VeoVa), these three dispersible polymer powders dominate the entire market, especially vinyl acetate and ethylene copolymer rubber powder VAC/E/VeoVa E, has a leading position in the global field and represents the technical characteristics of dispersible polymer powders. 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. Have the most application experience in the construction field;
3. It can meet the rheological properties required by the mortar (ie the required workability);
4. The polymer resin with other monomers has the characteristics of low organic volatile compounds (VOC) and low irritating gases;
5. It has the characteristics of excellent UV resistance, good heat resistance and long-term stability;
6. It has high saponification resistance;
7. Has the widest glass transition temperature range (Tg);
8. It has relatively good comprehensive bonding, flexibility and mechanical properties;
9. Have the longest experience in chemical production on how to produce stable quality products and experience in maintaining storage stability;
10. It is easy to combine with the protective colloid (polyvinyl alcohol) with high performance.
2. Resin powder
Most of the “resin” rubber powders on the market contain the chemical substance DBP. You can check the harmfulness of this chemical substance, which affects male sexual function. A large number of such rubber powders are piled up in warehouses and laboratories, and they are volatile to a certain extent. The Beijing market, which is famous for its production of “rubber powder”, has now emerged a kind of “rubber powder” soaked in solvents with various names: high-strength water-resistant adhesive powder, resin adhesive powder, etc. Typical features:
1. Poor dispersibility, some feel wet, some feel flocculent (it should be a porous material like sepiolite), and some are white and slightly dry but still smelly;
2. Smells very pungent;
3. Some colors have been added, and the current colors are white, yellow, gray, black, red, etc.;
4. The addition amount is very small, and the addition amount for one ton is 5~12 kg;
5. The early strength is amazing. The cement has no strength for three days, and it can corrode the insulation board and stick it.
6. It is said that the XPS board can be used without interface agent.
Through the samples obtained so far, it can be concluded that it is a solvent-based resin adsorbed by lightweight porous materials, but the supplier wants to avoid the word “solvent” deliberately, so it is called “rubber powder”
shortcoming:
1. The weather resistance of the solvent is a big problem. In the sun, it will volatilize in a short time. Even if it is not in the sun, the bonding interface will decompose faster due to the cavity construction;
2. Aging resistance, solvent is 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 in the later stage, the impact will be fatal;
4. There is no precedent for application abroad. With the mature experience of basic chemical industry abroad, it is impossible not to discover this material.
summary:
Available in dispersible latex powder:
1. The redispersible latex powder product is a water-soluble redispersible powder, which is a copolymer of ethylene and vinyl acetate, and uses polyvinyl alcohol as a protective colloid.
2. VAE redispersible latex powder has film-forming properties, 50% aqueous solution forms an emulsion, and it forms a plastic-like film after being placed on glass for 24 hours.
3. The formed film has certain flexibility and water resistance. Can reach national standards.
4. The redispersible latex powder has high performance: it has high bonding ability, unique performance and outstanding waterproof performance, good bonding strength, endows the mortar with excellent alkali resistance, and can improve the adhesiveness and flexural strength of the mortar. , plasticity, wear resistance and construction, it has stronger flexibility in anti-cracking mortar.
Resin powder:
1. Resin rubber powder is a new type of modifier for rubber, resin, macromolecular polymer, ground rubber powder and other substances.
2. Resin rubber powder has general durability, abrasion resistance, poor dispersibility, some feel flocculent (it should be a porous material like sepiolite), and white powder (but has 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 rubber powder are lower than those of latex powder. Weather resistance is a big problem. In the sun, it will volatilize in a short time. Even if it is not in the sun, the bonding interface, Since it is a cavity construction, it will also decompose faster.
5. Resin rubber powder does not have moldability, nor flexibility. According to the inspection standard of external insulation mortar for external walls, only the destruction rate of polystyrene board meets the standard. Other indicators are not up to standard.
6. Resin glue powder can only be used for bonding polystyrene boards, not for bonding of vitrified beads and fireproof boards.