Regarding the problem that the putty powder is easy to powder, or the strength is not enough. As we all know, cellulose ether needs to be added to make putty powder, HPMC is used for wall putty, and many users do not add redispersible latex powder. Many people do not add polymer powder in order to save costs, but this is also the key to why ordinary putty is easy to powder and prone to product quality problems!
Ordinary putty (such as 821 putty) is mainly made of white powder, a little starch glue and CMC (hydroxymethyl cellulose), and some are made of methyl cellulose and Shuangfei powder. This putty has no adhesion and is not water resistant.
Cellulose can absorb water and swell after being dissolved in water. Products from different manufacturers have different water absorption rates. Cellulose plays a role in water retention in putty. The dried putty only has a certain strength temporarily, and it will slowly de-powder after a long time. This is closely related to the molecular structure of cellulose itself. Such putty is loose, has high water absorption, is easy to pulverize, has no strength, and has no elasticity. If topcoat is applied on top, low PVC is easy to burst and foam; high PVC is easy to shrink and crack; due to high water absorption, it will affect the film formation and construction effect of topcoat.
If you want to improve the above problems of the putty, you can adjust the putty formula, add some redispersible latex powder appropriately to improve the later strength of the putty, and choose high-quality hydroxypropyl methylcellulose HPMC with guaranteed quality.
In the process of putty production, if the amount of redispersible latex powder added is not enough, or if inferior latex powder for putty is used, what impact will it have on the putty powder?
Insufficient amount of putty redispersible latex powder, the most direct manifestation is that the putty layer is loose, the surface is pulverized, the amount of paint used for topcoating is large, the leveling property is poor, the surface is rough after film formation, and it is difficult to form a dense paint film. Such walls are prone to peeling, blistering, peeling, and cracking of the paint film. If you choose inferior putty powder, it is obvious that harmful gases such as formaldehyde produced on the wall will cause physical harm to others.
Post time: Jun-15-2023