Development and evaluation of an acrylic lubricant for PVC formulations.

Abstract

One of Kaneka Belgium's activities is the development and production of additives for PVC in order to improve its properties. Lubricants, for instance, are added to the PVC formulation to reduce friction and melt viscosity in order to improve processing. However, current lubricants tend to display plate-out, which is an uncontrolled deposition on machinery parts. Therefore, this master's thesis aimed to develop a low molecular weight acrylic lubricant that is sufficiently compatible with the PVC matrix to avoid plate-out.

The acrylic lubricant was synthesized via free radical suspension polymerization. Parameters of the polymerization process, such as temperature, initiator type, initiator concentration, emulsifier type, emulsifier concentration and addition of chain transfer agents were methodically adapted. As a result, a recipe was achieved that produces low molecular weight acrylic polymers. From the different polymerization tests, promising acrylic polymers were evaluated on their lubricating properties by Brabender gelation and shear viscosity measurements. Results of these tests were compared to the lubricating properties of standard lubricants.

A recipe to produce low molecular weight lubricating acrylic polymers was successfully developed. The acrylic polymers displayed similar lubricating properties compared to current lubricants according to Brabender gelation and shear viscosity measurements.