hydroxypropyl methylcellulose HPMC in Plastering MortarFebruary 2nd 2023
After the putty has dried and been de-powdered, the root cause can be attributed to the fact that the bonding system did not work. Why the bonding system, whether it is an inorganic binder or an organic binder, can be considered from the following aspects.
1. The quality of the binder in the putty itself is faulty.
2. The binder does not work. The bonding mechanism of a binder is a wet mortar containing glue powder. As the base absorbs water, the water-hard material is consumed, the surface layer evaporates into the air and the resin particles gradually come closer together. The interface gradually becomes blurred and the resins gradually fuse with each other, eventually becoming a continuous polymer connector.
This process takes place mainly in the pores and solid surfaces of the mortar, resulting in a bonding action. However, if we scrape the putty layer too thin or force it to dry or dry after batching, the moisture will dissipate too quickly and the resin particles of the adhesive will not form a good bond well, thus losing the bonding effect.
Construction Grade Hpmc
Construction Grade Hpmc
If the powder drips gently, treat the floating plaster with a damp towel, then cure the wall for interfacial treatment and scrape. Pay attention to the thickness of the scraping; if the putty layer is heavily chalked, wall fixing is recommended. The interface is treated and then scraped off.
What should I do if the putty layer is blistered and empty?
The main reason is that the putty layer is hollow and blistered. The main reason is that there is gas between the base layer and the putty layer, why the air does not diffuse into the normal layer and spread to the base, but appears in the middle.
The main reasons are as follows: improper treatment of the base layer so that the putty layer is not in close enough contact with the base layer, forming a sandwich; a dense layer between the base layer and the putty layer, such as an interface agent or waterless wall solid for interface treatment, so that the air does not diffuse properly to the base layer.
If the wall bubble or bulge is small, use sanding treatment, then wall curing treatment, then scraping; if the wall is very large and has caused large areas to fall off, it is recommended that all be used after eradication. Solid treatment, then scraping in batches.
How is the cracking of the putty layer caused?
There are many reasons why putty cracks. There are external causes and internal causes. From the outside, dry and wet changes form dry shrinkage cracks; temperature changes and thermal expansion and contraction cause temperature cracks; static loads on the wall structure deformation cause structural cracks. Internally, factors such as product quality, construction techniques (batch thickness, interface treatment) and maintenance methods can all lead to cracking of the putty.
Micro-cracks caused by wet and dry, temperature changes or batch scraping: can be sanded, brushed, cured and carefully controlled.
Large cracks caused by thick scraping, etc., shovelled out, wall fixed and puttyed again.
Large cracks caused by cracked walls, after painting, painting the wall, applying mesh and then scraping putty. If the wall cracks are large, the wall crack treatment programme should be dealt with.
If you want to get more information about the construction grade HPMC, welcome to contact us today or request a quote.