Influence of Molecular Weight and Crystallinity of HDPE upon the Initial Friction and Transfer Behavior

Publisher Website
Google Scholar
Abstract
The influence of molecular weight, crystalline structure, and surface energy of high-density polyethylene (HDPE) upon initial friction and transfer behavior was studied on a pin-and-disk tribometer, at low speed (1.6 mm/s) 20°C and 12 percent relative humidity, using: (a) Composite PE pins made from thin film (< 400 μm) of defined molecular weight, Mw (5.104, 4.105, 4.106 g/Mole) and crystalline structure, controlled by the temperature of crystallization (120°C < Tc < 132°C), stuck onto a PE support (6 × 6 × 20 mm) (b) Thoroughly polished, plasma-cleaned steel disks (Ra < 0.02 μm) It was shown, that any increase in the PE surface energy (by plasma or chemical treatment) greatly influences the initial friction and transfer behavior. Depending on the superficial cross-linking density, which is dependent upon the surface treatment, either transfer of polymer onto the metal, or the formation of metal-containing transfer particles on the polymer is promoted during the first few rotations. The influence of the crystalline morphology (spherulite or axialite) and Mw on friction is also described.

This publication has 14 references indexed in Scilit: