Apparent viscosity is an important indicator of hydroxypropyl methylcellulose, commonly used measurement methods include rotational viscometry, capillary viscometry and drop viscometry.
Hydroxypropyl methylcellulose was previously measured using capillary viscometry using an Ubbelohde viscometer. Usually the measurement solution is an aqueous solution of 2, the formula is: V = Kdt. V represents the viscosity, K is the constant of the viscometer, d represents the density at a constant temperature, t refers to the time from the top to the bottom of the viscometer, the unit is second, this method is cumbersome to operate and it is easy to cause Wrong, and it is difficult to distinguish the quality of hydroxypropyl methylcellulose.
The problem of delamination of construction glue is a big problem encountered by customers. First of all, the problem of raw materials should be considered for the construction glue layer. The main reason for the construction glue layer is that polyvinyl alcohol (PVA) and hydroxypropyl methylcellulose (HPMC) are not compatible. The second reason is that the stirring time is not enough, and the thickening performance of the construction glue is not good.
The hydroxypropyl methylcellulose (HPMC) of the present invention needs to be used in construction glue, because hydroxypropyl methylcellulose (HPMC) is dispersed in water and cannot really dissolve, and the viscosity of the liquid increases gradually in about 2 minutes, forming Transparent viscous colloid.
When hot melt products are mixed together in cold water, they will quickly disperse in hot water and disappear in hot water. When the temperature drops to a certain temperature, the viscosity will appear slowly until a transparent viscous colloid is formed. Hydroxypropyl in construction adhesive The recommended dosage of HPMC is 2-4kg.
Hydroxypropyl methylcellulose (HPMC) has stable chemical properties, mildew resistance and good water retention in construction adhesives, and is not affected by pH changes. It can be used from 100,000 S to 200,000 S, but the higher the viscosity in production, the better, and the viscosity is inversely proportional to the bonding strength. The higher the viscosity, the lower the strength, generally the viscosity of 100,000 S is appropriate.
Post time: Apr-20-2023