Characteristics of sealants as construction materials
Modern construction technologies are increasingly using all kinds of sealants, materials that allow you to safely seal joints, cracks, hide and isolate minor and minor defects without much difficulty. Efficiency and manufacturability of application makes them indispensable in many types of work, for example, with responsible insulation works.
All sealants provide high strength and resistance to deformation, have high adhesion, are elastic and durable in use( outside and inside structures).The formulations used in modern hermetics contain polymers( polysulphides or liquid silicone rubbers), they provide simple application of sealant. As a rule, the manufacturer produces single-component formulations in special tubes.
This package allows you to mechanically squeeze the mass( using pistol and other devices) through special cone nozzles into the filled spaces. With this technology, a spatula for sealing is often not required.
Although the fluidity and adhesion properties of most formulations make it possible to obtain a uniform opaque layer, if necessary, the surface of the composition can be leveled with an appropriate tool.
What should I remember when I start working?
It is clear that the readiness for use is one of the factors determining how to use the sealant. If one-component formulations are ready for use immediately after release, multicomponent products require preliminary preparation with the need to strictly observe the proportions and maintain the mixing technology specified by the manufacturer, before using the sealant. Only in this case, adhesion and all its physical, chemical and mechanical properties are guaranteed.
In addition to being ready for use, the compositions may differ in chemical composition. There is a great variety: there are based on silicones, acrylic polymers, polyurethane, based on butyls and based on bitumen polymers. Undoubtedly, these features determine how to apply sealant on the surface.
Continuous development and improvement of production technologies of these compounds makes it possible to use sealants in parts and engine components at high temperatures and corrosive environments. Each species has a specific field of application. For example, acrylics are recommended for indoor use and do not withstand outdoor use.
How to work with a sealant?
Perhaps the most universal are the widely used silicone sealants. They provide high performance and long service life. Good adhesion is responsible for the reliability of the layer, even on glass or glazed tiles. During the tests, the silicone sealants were more likely to break down at the seam, rather than in contact with the materials to be sealed.
There are little secrets in all activities. And in how to properly use the sealant, there are also nuances. For example, when sealing joints to ensure a long and reliable service, the ratio of depth and width of the joint should not exceed two to three.
If the depth of the seam is larger( in most cases it is), a special polyethylene cord is pre-tightly inserted into the seam. If necessary, it is easy to make from a conventional polyethylene bag or bag. With a sufficiently wide seam, to eliminate the adhesion of the sealant, a strip of polyethylene is applied to the three planes.
And, in conclusion, it must be said that the surfaces must be carefully prepared before using the sealant. They are cleaned, degreased, if necessary( depending on the material) primed with special formulations.
To obtain a smooth weld surface, use a special spatula for sealant( its width should correspond to the width of the processed seams).For this, special screeds and sprays can be used.