Presenters Name:James Manikath
Employment Title: Technical Manager
Company: Luxury Paints, Darra, QLD
Biography: James is responsible for over all technical management and compliance at Luxury Paints, Queensland. Has extensive experience in industrial and academic research. He has worked at Nuplex Industries, PPG and Wattyl gaining formulation experience in polymer latexes and coatings. Before that he was a Research Fellow in School of Engineering at the University of Auckland.
Presentation Title: PPolymer Properties Less Commonly Known, Yet Critical to Coating Performance
Presentation Abstract: While developing a quick-drying paint with an excellent finish, mud cracks were observed after 24 hours or later. To address this issue, various polymers and blends were tested. However, softer polymers delayed the hardening process and caused blocking.
In this context, I reviewed the research I conducted at the University of Auckland, School of Engineering, on stress relaxation in polymers used in plastic composites. This work examined the gradual reduction of internal stress within various composites, providing valuable insights into achieving shape stability in certain plastic objects under load.
As a paint or coating dries and cures, the polymer chains transition from a liquid to a solid state. This process involves significant shrinkage, which can induce internal stresses within the film. Relaxation mechanisms of polymer molecules allow the polymer chains to rearrange, reducing these internal stresses.
Various factors affecting the stress relaxation of coatings have been examined. The related properties like creep in polymers, used in coatings, have also been reviewed, and valuable insights were gained.
Stress reduction plays a crucial role in the performance of paints and coatings. A thorough understanding of this phenomenon contributes to the development of defect-free coatings with improved flexibility, durability, and adhesion. Gaining deeper insights into often-overlooked polymer properties equips coating formulators with the knowledge needed to make informed decisions regarding polymer selection.
