PVC Micropellets Replace Drysols and Plastisols in Rotocasting Interior Automotive Applications

Polyvinyl chloride (PVG) compounders have recently shown a growing interest in the use of micropellets for rotational molding and casting applications. Specifically, micropellets with diameters ranging from 0.020 to 0.060 inches (0.5 to 1.5 mm) are currently being rotationally casted for interior automotive applications. PVC micropellets offer several advantages over the drysols and plastisols that have been predominately used for rotational molding and casting.

The primary advantage of drysol and plastisol use by PVC compounders is their relative ease of manufacture. Drysols are PVC dryblends that have been modified for ease of flow when in contact with a heated surface and without the presence of shear. Plastisols are a paste form of the same material and are best suited for slush molding and rotational casting. There can be significant disadvantages for the use of both of these forms of PVC. Drysols are difficult to manufacture at durometers of 55 A and below. Adding polymer modifiers to plastisol may result in a compound with inadequate end-use performance properties.

As a new alternative to plastisols and drysols, PVC micropellets combine the ease of manufacture and several other advantages. Micropellets are controlled to a target particle size and distribution which is necessary depending on the geometric shape of the part. Other advantages include cleaner handling and environmentally friendly attributes.