How to identify the performance of sealant
There are many kinds of sealants: silicone sealant, polyurethane sealant, polysulfide sealant, epoxy sealant, butyl sealant, neoprene sealant, PVC sealant, asphalt sealant, etc.
The main properties of sealant are as follows:
1. Breaking strength (tensile force/cross-sectional area)
2. Bonding strength (pulling force/bonding area, except base material damage)
3. Elongation at break (length at break/original length)
4. Soothing aging ability
5. Appearance (sub luminosity, particles, bubbles)
6. Shape retention (no wire drawing, no sagging facade) 7. Shelf life 8. Curing time
What I want to tell you is that there is no good or bad adhesive. The performance corresponds to the price, and it is good to be suitable. Secondly, there is stability and adequacy, which is the test of the manufacturer. If the capacity of the sealant is less than the marked capacity, the situation of the sealant is very serious. Such sealant should be eliminated first. It is recommended to select a large manufacturer or package it formally, and introduce the detailed product.
The two-component polysulfide sealant is a liquid rubber as the main base material, added with a variety of chemical additives, and made by a special polymer material synthesis process. It is a new harmless waterproof sealing material. The product has excellent water resistance, oil resistance, aging resistance, and corrosion resistance. It is famous for its good sealing performance, strong adhesion, good elasticity, and long service life.
The two-component polysulfide sealant is made of liquid polysulfide rubber as the main agent, with reinforcing agent, toughening agent, tackifier, thixotropic agent and other additives added to prepare and process the base paste; The metal oxide is used as the curing paste, and the two components can be mixed to solidify into an elastic sealing material.
The two-component polysulfide sealant is a kind of normal temperature vulcanized two-component building B first-class polysulfide sealant with self bonding performance with concrete and liquid polysulfide rubber as the base material, which has the ability of caulking and water sealing.
The other kind of polysulfide sealant is two-component. Component A is barreled white paste, and component B is bottled liquid curing agent (for the convenience of the construction party's requirements for pigments, the colors are separately boxed, one in one group). When using, squeeze all component B liquid into component A bucket, put in pigment according to the construction color requirements, and quickly mix up and down until uniform. Use a small shovel to apply the mixed sealant to the parts to be constructed. After 48 hours, it can be immersed in water and contacted with water
Cause analysis of quality problems found in two-component polysulfide sealant:
1. The quality of polysulfide sealant does not meet the requirements of relevant standards, or meets the requirements of standards but cannot meet the requirements of the actual application of the project; For example, the sealant exposed to the sun for a long time needs to strengthen its ability to prevent direct radiation; The sealant soaked in sewage or still water for a long time needs anti mold treatment, otherwise it is easy to cause damage to the sealant.
2. Damage caused by irresistible external force of sealant, such as sharp tool penetration, concrete plate cracking, etc.
3. Damage caused by uneven mixing and poor curing of sealant.
4. The interface is not cleaned up, resulting in a large area of single-sided cracking.
5. Damage caused by insufficient glue coating.
Two component waterproof polysulfide sealant A, B Pour the two groups on the same glass plate or floor tile at the same time (the floor tile is required to be 60 cm square is better). According to the mix ratio given in the specification, the mix ratio A: B=100:10~100:14 (mass ratio), mix the two components evenly, and then use them. At the time of delivery, our company has prepared the mix ratio according to the mass ratio, and opened the box separately with plastic cylinders, Users don't need to worry about the mass ratio. When using, they just need to open the package and put component A and component B together and stir them evenly.
The two-component waterproof polysulfide sealant has excellent resistance to fuel, hydraulic oil, water and various chemicals, as well as heat resistance and atmospheric aging resistance. It is generally vulcanizable. According to the composition, it can be divided into two components (or three components) and one component type. The process of premixing grinding filling is adopted.
The two-component polysulfide sealant is made of liquid polysulfide rubber as the main base material, adding a variety of chemical additives, and through a special polymer material synthesis process. It is a two-component sealant that can self vulcanize and cross link at room temperature. It has good adhesion to metal, concrete and other materials, and can maintain good air tightness and water resistance under continuous expansion, vibration and temperature changes, It can keep good air tightness and waterproof under continuous expansion, vibration and temperature change, and has good oil resistance, solvent resistance and durability.
