Feasibility of Using Saltcedar as a Filler in Injection-Molded Polyethylene Composites

Authors

  • Craig M. Clemons
  • Nicole M. Stark

Keywords:

Saltcedar, tamarisk, polyethylene, wood-plastic composite, WPC, filler, wood flour, injection molding

Abstract

Saltcedar (Tamarix ramosissima) was investigated for use as a filler in wood-plastic composites (WPCs). The mineral content, water-soluble extractive content, and thermal stability of saltcedar flour were compared with those of a commercial pine wood flour. The wood flours were compounded with plastic, and the viscosities of the composite melts containing the two species were compared. Injection-molded composites produced from the compounded material were evaluated for mechanical performance and weatherability. Saltcedar flour had more minerals and water-soluble extractives than pine flour, which resulted in lower thermal stability, but also lower melt viscosity when compounded with high-density polyethylene. Injection-molded WPCs made from unextracted saltcedar performed similarly to those made from pine in accelerated weathering tests, but their mechanical properties were generally lower. The flexural modulus of elasticity increased when extracted wood flour was used, especially for the saltcedar composites. However, color stability and flexural strength changed little. Producing WPCs from these composites is possible, although economically feasible applications that use the advantageous properties of these species and that can tolerate or address the less desirable ones need to be identified and demonstrated.

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Published

2009-01-29

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Section

Research Contributions