External wall insulation and EIFS are used in the global field. The installation on the exterior wall of the building mainly save 40%-70% of the energy consumption of building heating and cooling. The polymer powder modified dry mortar is used to bond polystyrene sheets to the wall(bonding mortar). At the same time, in order to protect the polystyrene board and prevent aging under climatic conditions, a layer of about 3mm of alkali-resistant glass fiber reinforced polymer rubber powder modified protective mortar is covered on the surface layer of polystyrene, and finally covered as a decorative layer and a protective surface layer.
In the external thermal insulation and EIFS, or the external wall thermal insulation composite system, the bonding mortar must provide good bonding to the polystyrene board and various substrates, and the polymer plays an integral role in it effectively. For protective mortars and cement-based decorative mortars, polymer rubber powders provide good adhesion, impact resistance, low water absorption and high flexibility even under harsh climatic conditions.
In order to ensure the durability of the polymer in the modified mortar of the external thermal insulation system and to play its role as an organic adhesive for a long time, several additional experiments were carried out under more severe and near-real conditions. Generally, the curing conditions in the standard do not reflect the actual conditions of the mortar and the building. The test under the harsh test conditions is more comparable to the properties of the material and the polymer.
The mineral-based decorative mortar in the outer layer of the thermal insulation system must provide good adhesion to the protective mortar and low water absorption to satisfy its role as a decorative protective surface. With the increase of the polymer, not only the adhesion of the dry powder mortar finish layer is improved, but also the other properties are positively promoted. The special type of dispersible polymer powder can improve the performance of strong water, which can make the mortar have very low rate water absorption while maintain the hydrophobic effect for a long time.
- Dry powder insulation mortar
Dry powder insulation mortar is made of high-quality chemical resistance such as polystyrene foam particles, non-absorbent, high toughness, good crack resistance and excellent thermal insulation. It uses combined fiber, cellulose ether and rubber powder. Such high-quality dry mortar additive makes the mortar have thermal insulation performance, and guarantees construction, crack resistance and weather resistance. It is simple, economical and practical, dry-cleaning mortar with thermal insulation function, which can replace traditional mixing. Plastering mortar can also have good Jain insulation effect. The main performance indicators such as thermal conductivity can meet the needs of energy-saving buildings. It is a new type of material between the expanded perlite insulation material and the construction mortar. It only needs to be stirred with water to add plaster at the construction site. The same as ordinary mixed mortar.
In order to implement the national wall reform and building energy conservation goals, building energy conservation is becoming a new hot spot in the construction industry. The implementation of building energy conservation must greatly improve the external protective structure, especially the thermal performance of the external wall. Because the thermal insulation mortar has better thermal performance and convenient construction, the thermal resistance of the wall can be adjusted by changing the apparent density and thickness of the thermal insulation mortar, and the construction cost is low. The building energy-saving standards that have been formulated and are being formulated in the Yangtze River Basin in China, stipulate that the wall heat transfer is not more than 1.5W, and the thermal insulation mortar is determined to be one of the energy-saving measures to be adopted. In the past, the method was to prepare cement-expanded perlite thermal insulation mortar on site, and the construction was carried out by multiple batch scraping methods.
However, because the construction efficiency of this product is low during construction, and the water absorption rate is large, the crack resistance and the weather resistance are poor, the application has great limitations, the quality is not easy to control and guarantee, and the heat preservation performance needs to be improved. It is imperative to develop and apply thermal insulation mortar with better technical economy and promote the upgrading of thermal insulation mortar.
Modern dry mortar adopts lightweight aggregates with excellent chemical resistance, no water absorption, high toughness, good crack resistance and excellent thermal insulation properties, such as polystyrene foam particles, expanded perlite, etc. Excellent dry mortar additives such as ether and dispersible powder, which can significantly improve thermal insulation, workability, crack resistance and weather resistance. The apparent viscosity of the product is 460-880kg/m³, which can be used for exterior walls. Insulation solves the defects of traditional thermal insulation mortar on-site preparation and quality control. It conforms to the national policy on building energy conservation. The unit price per unit area is lower than that of the thermal insulation board. The market application prospect is very wide.
Advantages of dry insulation mortar: 1.It can be used with water, and the construction is convenient; 2.High bonding strength, not easy to hollow, falling off; 3. Physical and mechanical properties are stable, low shrinkage, preventing shrinkage cracking or cracking; 4. Construction on wet base; 5. Dry hardening, construction period is much shorter than traditional putty; 6. Safe and fireproof; 7. Hygienic, green and environmentally friendly; 8. Excellent heat insulation; 9. Low density, reducing the building’s own weight is conductive to structural design.
Type and basic formula of thermal insulation mortar
Insulation mortar materials include exterior wall insulation, interior wall insulation and roof insulation mortar. The high-rise building interior wall plastering material can be made of perlite thermal insulation mortar dry mortar. The perlite thermal insulation dry powder is prepared by mixing expanded perlite particles of different particles sizes with a certain proportion of adhesive and adding density of the product is 460-880kg/m³, and the color is from gray to pure white.
The thermal insulation mortar product is an ideal product to replace the traditional cement mortar and cement lime mixed mortar for interior wall plastering. It has a series of characteristics such as small apparent density, high bonding rate and remarkable energy saving effect.
4. Requirements for construction application of thermal insulation mortar
Basically similar to dry powder plaster, but its thickness should be set according to the requirements of thermal insulation. In addition, according to the crack resistance of the thermal insulation mortar, a crack-resistant reinforced mortar is set to meet the requirements of decoration and heat preservation functions.
1). Example of construction process of ordinary thermal insulation mortar with anti-crack protection layer
Clean the wall surface to ensure no loose materials and grease, mold release agent and other unfavorable bonding materials; wash the interface agent, if necessary, use dry mortar interface treatment or use film-forming or non-film forming emulsion interface treatment agent, generally In this case, a non-film-forming emulsion interface treatment agent is used for the superabsorbent base, and a film-forming emulsion interface treatment agent is used for the low-absorbency base.
Hang vertical, set square, find the rules, the specific requirements refer to the plaster mortar construction specifications, wipe the first time insulation mortar, straight, leveling, find a square, bullets, layered line; wipe the second time insulation mortar; Layering, dividing the seam; pressing into the mesh cloth, rubbing the cracking mortar; wiping the surface against the cracked mortar; scraping the putty, brushing the paint, acceptance.
2) High-quality thermal insulation mortar construction method flow without crack protection layer;
Layer operation according to wall design requirements. Before the plastering, the surface of the base layer should be checked for verticality and flatness with a line drop, and the formula should be found. According to the size of the wall surface, the thickness of the gray layer is affixed to the gray cake along the base of the skirting line.
Using the same mortar as the gray cake, a long trapezoidal ash is firstly smeared in the vertical direction between the adjacent two gray cakes, and the width is about 10cm, and the thickness is the same as that of the gray cake, which is used as a sign of the wall rib.
After rushing for about 2-3 hours, apply the bottom ash. When the bottom ash is smeared, it should be from bottom to top. Do not exceed 1cm thick. The force should be even. It should be lighter than the mortar. Make the ash layer not too solid and keep the ash layer. The void of the inner lightweight aggregate ensures the heat preservation effect, and the mortar and the brick wall are firmly bonded. After the bottom ash is applied to the wall for 4-6 hours, the middle layer ash can be applied. Wipe until it is slightly higher than the thickness of the rib. Then use a straight wooden bead to squeezing along the ribs. The same thermal insulation mortar should be applied to the depression immediately, and then flattened with a flat wooden bead, followed by a wooden slab to make the surface smooth and compact.
At the negative corner of the wall, use the square ruler to press the upper and lower sides of the square, and then use the positive angle trowel to smear up and down to make the four angles square.
After the middle layer mortar reaches the initial setting, the middle layer of gray is usually applied to the wall for 4-6 hours.
If you encounter concrete underfill or aerated brick wall, first use the interface treatment agent, then wipe the insulation mortar. According to the design requirements. the cover ash is always thin. Starting from the negative or positive angle, a layer is applied horizontally or longitudinally, which is firmly bonded to the middle layer. After initial setting, it is smoothed and compacted to make the surface smooth and smooth.