An experimental investigation on surface quality and water absorption of extruded wood–plastic composite

Autor: N Jafarian Jam, Amir Hossein Behravesh, Ehsan Soury, Ali Haghtalab
Rok vydání: 2011
Předmět:
Zdroj: Journal of Thermoplastic Composite Materials. 26:680-698
ISSN: 1530-7980
0892-7057
Popis: This article presents an experimental study on the relationship between surface quality (roughness) and water absorption for wood–plastic composites (WPCs) in an extrusion process. A problem that usually occurs in the production of extruded parts of polymeric materials, and in special case of WPC, is flow instabilities at the extrusion die exit. The instabilities lead to the production of profiles with unacceptable surface quality. In this article, the influences of the important material and process parameters on the surface quality and water absorption are investigated. The attempt was made to find a relationship between surface roughness and water absorption of WPC extruded profiles. The variable parameters were selected as wood content, polymer melt flow index (MFI), screw speed, melt temperature, die diameter, and finally length-to-diameter ratio ( L/ D) of the die land. The experiments specified that increasing die land L/D, die temperature and wood content and decreasing screw speed and polymer MFI lead to improved surface quality. It was found that increasing die diameter and also decreasing die land L/D, die temperature, speed, wood content, and polymer MFI lead to an improvement in water resistance. The results also showed that a rough surface quality could cause a low water resistance specification.
Databáze: OpenAIRE