HPMC used in Wall Putty/Skim Coat

HPMC can be divided into: construction grade, food grade and medical grade according to the use. At present China is construction grade mostly, in building class, Wall putty/Skim Coat the dosage of skim coat powder is very big. HPMC powder and a large number of other powdery material ingredients, fully mixed with blender, then add water to dissolve, at this time HPMC can dissolve, but not agglomerate, because each tiny corner, a little HPMC powder, water will immediately dissolve. Skim Coat powder and mortar production enterprise use this kind of method more. Hydroxypropyl methyl cellulose (HPMC) is used as thickener and water retaining agent in putty mortar.

The gel temperature of HPMC is related to the methoxyl content, the lower the methoxyl content down, the higher the gel temperature up. HPMC cold water instant solution type is after glyoxal surface treatment, put in cold water quickly dispersed, but not really dissolved, viscosity up, is dissolved. The thermosoluble HPMC type has not been surface treated with glyoxal. The amount of glyoxal is large, the dispersion is fast, but the viscosity is slow, the amount is small, on the contrary. HPMC can be divided into instant and heat soluble, instant products, in cold water quickly dispersed, disappeared in the water, at this time the liquid has no viscosity, because HPMC is just dispersed in the water, there is no real dissolution. About 2 minutes, the viscosity of the liquid gradually increases, forming a transparent viscous colloid. Heat soluble products, in cold water agglomeration, can be in hot water, quickly dispersed, disappear in hot water, until the temperature drops to a certain temperature, viscosity slowly appear, until the formation of transparent viscous colloid. Heat soluble type can only be used in Skim Coat  and mortar, in liquid glue and coating, can appear agglomeration phenomenon, can not be used. Instant dissolve model, application scope is a few wider, in Skim Coat powder and mortar, and in liquid glue and coating, all can be used, do not have what taboo.

Solvent method of production of HPMC, is made of toluene, isopropyl alcohol solvent, if the washing is not very good, there will be some residual taste.  the application of Skim Coat  powder: the requirement is inferior, viscosity 100000, it is important to protect water to be close to. Mortar application: higher requirements, high viscosity requirements, 150000 to be better. Glue application: the need for instant products, high viscosity. HPMC in the actual application of the amount, by the climate environment, temperature, local gray calcium quality, Skim Coat  formula and “customer requirements of the quality” of the different, and there are differences. Hydroxypropyl methyl cellulose (HPMC) of viscosity – Skim Coat powder is 100000, some taller of the requirement in mortar, want 150 thousand ability to use. Moreover, HPMC’s main role is to retain water, followed by thickening. In Skim Coat , as long as the water retention is good, the viscosity is low (7-80000), it is also possible, of course, the viscosity is bigger, the relative water retention is better, when the viscosity is more than 100000, the viscosity of water retention is not much; Hydroxypropyl content is high, water retention is generally better. Viscosity, water retention, relatively better, and viscosity, in the cement mortar is better used.

HPMC in Skim Coat , thickening, water retention and construction of three functions. Not participating in any reaction. The cause of the bubble may be too much water, may also be the bottom is not dry, on the top of a layer of scraping, also easy to bubble. HPMC in the thickening effect of Skim Coat : cellulose can be thickened to suspension, so that the solution remains uniform up and down the role of anti-flow hanging. HPMC water retention effect in Skim Coat : make Skim Coat  dry slowly, auxiliary gray calcium reaction under the action of water. HPMC in Skim Coat  construction role: cellulose lubrication, can make Skim Coat has good construction. HPMC does not participate in any chemical reactions, but only plays a supporting role.

Wall putty/Skim Coat powder and the main ash calcium quality has a great relationship, and HPMC does not have a great relationship. The low calcium content of gray calcium and the improper proportion of CaO and Ca(OH)2 in gray calcium will cause powder dropping. If there is a little relationship with HPMC, then it is HPMC poor water retention, will also cause the powder, Skim Coat  and water, on the wall, is a chemical reaction, because of the generation of new substances, the wall of Skim Coat  down from the wall, ground into powder, and then use, not line, because has formed a new substance (calcium carbonate). The main components of grey calcium powder are: Ca(OH)2, CaO and a small amount of CaCO3 mixture, CaO+H2O=Ca(OH)2 – Ca(OH)2+CO2=CaCO3↓+H2O gray calcium in water and air under the action of CO2, the formation of calcium carbonate, and HPMC only water, auxiliary gray calcium better reaction, its own did not participate in any reaction.

Formula of all kinds of wall putty powder:

1, ordinary inner wall putty powder formula

Redispersible polymer powder RDP 2 ~ 2.2%, double fly powder (or talc) 98% HPMC 0.4%

2, ordinary high hard inner wall putty powder formula

Redispersible polymer powder RDP 1.8 ~ 2.2%, double fly powder (or talc powder) 90 ~ 60%, plaster of Paris (building gypsum, half water gypsum)10 ~ 40% HPMC 0.4%

3, high hardness and water resistant inner wall putty powder reference formula

Formula 1: Redispersible polymer powder RDP 1 ~ 1.2%, double fly powder 70%, lime calcium powder 30% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 0.8 ~ 1.2%, double fly  powder 60%, gray calcium powder 20%, white cement 20% HPMC 0.4%

4. High hardness, washable and mildew proof inner wall putty powder reference formula

Formula 1: Redispersible polymer powder RDP 0.4 ~ 0.45%, double fly powder 70%, ash calcium powder 30% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 0.4 ~ 0.45%, double fly powder 60%, gray calcium powder 20%, white cement 20% HPMC 0.4%

5. Reference formula of high hardness, water resistant and crack resistant exterior wall putty powder

Formula 1: Redispersible polymer powder RDP 1.5 ~ 1.9%, white cement (black cement) 40%, double fly powder 30%, gray calcium powder 30%, crack prevention additive 1 ~ 1.5% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 1.7-1.9%, white cement (black cement) 40%, double fly powder 40%, gray calcium powder 20%, crack prevention additive 1-1.5% HPMC 0.4%

Formula three: Redispersible polymer powder RDP 2 ~ 2.2%, white cement (black cement) 40%, double fly  powder 20%, gray calcium powder 20%, quartz powder (180# sand)20%, crack prevention additive 2 ~ 3% HPMC 0.4%

Formula four: Redispersible polymer powder RDP 0.6-1%, white cement (425#) 40%, gray calcium powder 25%, double fly powder 35%, anti-cracking additive 1.5% HPMC 0.4%

Formula five: Redispersible polymer powder RDP 2.5 ~ 2.8%, white cement (black cement) 35%, double fly powder 30%, gray calcium powder 35%, crack prevention additive 1 ~ 1.5% HPMC 0.4%

6, elastic washable exterior wall anti-crack putty powder reference formula

Redispersible polymer powder RDP 0.8 ~ 1.8%, white cement (black cement) 30%, double fly powder 40%, gray calcium powder 30%, crack prevention additive 1 ~ 2% HPMC 0.4%

7, Mosaic strip tile wall anti-crack putty powder reference formula

Formula 1: Redispersible polymer powder RDP 1 ~ 1.3%, white cement (425#) 40%, gray calcium powder 20%, double fly powder 20%, anti-cracking additive 1.5%, quartz sand 120 mesh (or dried river sand) 20% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 2.5 ~ 3%, white cement (black cement) 40%, double fly  powder 20%, gray calcium powder 20%, quartz powder (180# sand) 20%, crack prevention additive 2 ~ 3% HPMC 0.4%

Formula three: Redispersible polymer powder RDP 2.2 ~ 2.8%, white cement (black cement) 40%, double fly powder 40%, gray calcium powder 20%, crack prevention additive 1 ~ 1.5% HPMC 0.4%

8, elastic Mosaic tile exterior wall washable anti crack putty powder reference formula

Redispersible polymer powder RDP 1.2 ~ 2.2%, white cement (black cement) 30%, double fly powder 30%, gray calcium powder 20%, quartz powder (sand) 20%, crack prevention additive 2 ~ 3% HPMC 0.4%

9, flexible inner wall putty powder reference formula

Formula 1: Redispersible polymer powder RDP 1.3 ~ 1.5%, double fly powder 80%, ash calcium powder 20% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 1.3 ~ 1.5%, double fly powder 70%, ash calcium powder 20%, white cement 10% HPMC 0.4%

10, flexible exterior wall putty reference formula

Formula 1: Redispersible polymer powder RDP 1.5 ~ 1.8%, double fly powder 55%, gray calcium powder 10%, white cement 35%, anti-cracking additive 0.5% HPMC 0.4%

11, color exterior wall putty powder formula

Color putty Redispersible polymer powder RDP 1-1.5%, white cement 10%, refined gray calcium powder (calcium oxide ≥70%) 15%, crack prevention additive 2%, bentonite 5%, quartz sand (whiteness ≥85% silicon ≥99%) 15%, yellow jade powder 52%, color putty modifier 0.2% HPMC 0.4%

12, ceramic tile adhesive formula

Ceramic tile adhesive adhesive powder 1.3%, ordinary Portland cement 48.7%, building sand (150~30 mesh) 50% HPMC 0.4%

13, dry powder interface agent formula

Dry powder interface agent Redispersible polymer powder RDP 1.3%, ordinary Portland cement 48.7%, building sand (150~30 mesh) 50% HPMC 0.4%

14, ceramic tile mildew sealant formula

Formula 1: Redispersible polymer powder RDP 1.5 ~ 2%, ordinary Portland cement 30%, high alumina cement 10%, quartz sand 30%, double fly powder 28% HPMC 0.4%

Formula two: Redispersible polymer powder RDP 3 ~ 5%, ordinary Portland cement 25%, high alumina cement 10%, quartz sand 30%, double fly powder 26%, pigment 5% HPMC 0.4%

15, dry powder waterproof coating formula

Waterproof coating Redispersible polymer powder RDP 0.7 ~ 1%, cement (black cement) 35%, gray calcium powder 20%, quartz sand (fineness >200 mesh) 35%, double fly powder 10% HPMC 0.4%

16, gypsum adhesive powder formula

Formula 1: gypsum adhesive powder 0.7 ~ 1.2%, plaster of Paris (half water gypsum, gypsum powder) 100% HPMC 0.4%

Formula two: gypsum adhesive powder 0.8 ~ 1.2%, plaster of Paris (half water gypsum, gypsum powder) 80%, double fly powder (heavy calcium) 20% HPMC 0.4%

17, paint gypsum powder formula

Formula one: gesso stucco powder 0.8 ~ 1%, plaster of Paris (half water gesso, gesso powder) 100% HPMC 0.4%

Formula 2: gesso stucco powder 0.8 ~ 1.2%, plaster of Paris (half water gesso, gesso powder) 80%, double fly powder (heavy calcium) 20% HPMC 0.4%

18. Formula of water-based wood putty powder

Water – borne wood putty Redispersible polymer powder RDP 8 ~ 10%, double fly powder (heavy calcium powder) 60%, gypsum powder 24%, talc powder 6 ~ 8% HPMC 0.4%

19, high anhydrite putty powder formula

putty gum powder 0.5 ~ 1.5%, plaster of cooked plaster powder (building gesso, half water gesso) 88%, talc powder (or double fly powder) 10%, gesso delay coagulant 1% HPMC 0.4%

20. Formula of ordinary gypsum putty powder

Latex powder 1 ~ 2%, plaster of cooked plaster (building gesso, half water gesso) 70%, talc powder (or double fly powder) 30%, gesso delay coagulant 1% HPMC 0.4%