1.Brief Introduction
HPMC-Hydroxypropyl Methyl Cellulose and Methyl Hydroxyethyl Cellulose and non-ionic cellulose ether made by natural high polymer cellulose as raw material and series of chemical processing. They are odorless, tasteless and non-toxic white powder, which can be dissolved in cold water to form a transparent viscous solution. Processing thickening, binding, dispersing, emulsifying, film, coating, suspending, absorbing, gelling, surface activity, water maintaining and protective colloid properties.
2.Parameter:
Items | Technical data | Units |
Appearance | White or off-white powder | |
Methoxy | 27%~30% | % |
Hydroxypropoxy | 4%~7.5% | % |
Viscosity range (2%,Brookfield) | 40-60 | mPa.S |
PH Value | 5-8 |
3.HPMC for PVC Description:
In PVC, HPMC is often used as a dispersant, thickener or binder.
As a dispersant, HPMC helps to disperse the PVC resin particles in the solvent, resulting in a more homogeneous mixture. This improves the quality and consistency of PVC products.
As a thickener, HPMC can increase the viscosity of PVC resin solutions, making it easier to control flow and improve the properties of the final product.
As an adhesive, HPMC improves the bond between PVC and other substrates such as wood, metal or concrete. This works to good effect where PVC is used as a construction additive for coatings or adhesives, as well as other related applications.
HPMC for PVC Advantages:
1. When acting on suspension polymerization, it can reduce the interfacial tension between vinyl chloride monomer (VCM) and water. It is conducive to the uniform and stable dispersion of VCM in the aqueous medium.
2. Prevent the coalescence of VCM droplets in the early stage of polymerization.
3. Prevent the coalescence of polymer particles in the later stage of polymerization.
4. In the suspension polymerization system, it plays the dual role of dispersion and stability protection.
5. With the increase of HPMC viscosity and the decrease of hydroxypropyl content. The interfacial tension increases and the dispersing ability decreases. Glue holding capacity is increased. The average particle size of PVC resin increases, the resin porosity decreases, and the apparent density increases.
6. Increasing the concentration of HPMC can improve its adhesive retention ability and reduce the average particle size of the resin.
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