If you are looking for high-quality products, please feel free to contact us and send an inquiry, email: brad@ihpa.net
pvc calcium improves base properties of pvc compounds such as impact strength, tensile strength and elongation at break. It also contributes to improved compounding performance by improving dispersion of various ingredients into the pvc powder blend and improving processing by making polymer flow more homogeneous.
Precipitated calcium carbonate (PCC) is a versatile additive that has been widely used in PVC for many years to provide a cost-performance ratio. Its regular & controlled crystalline shape and ultrafine particle size together with its hydrophobic surface coating, combine to benefit both polymer processing and subsequent physical properties.
Calcite Stearate in Rigid PVC:
Calcium stearate can be prepared by either the precipitation or fusion methods. The fusion method produces a much harder and larger calcium stearate than the precipitation process. This larger particle size may cause a delay in the fusion of rigid PVC during the early stages of compounding.
In addition, fusion calcium stearate may increase the melt viscosity and shear rate/volumetric flow rate in rigid PVC. This can be counter to the normal lubricating influence of stearic acid on PVC.
For these reasons, a formulation containing a combination of both precipitated and fusion calcium stearate may be preferred. This will allow high production output rates without the need for the higher usage of processing aids that may otherwise be required to assist the fusion characteristics of a particular compound. It will also allow a greater degree of flexibility in the selection of different types of calcium stearate depending on specific property requirements.