Injection Molding (October 01, 2003)

Project tests conditions for injection molding wood-filled materials

A recent study carried out by Battenfeld proposed to identify reliable, reproducible parameters for the injection molding of wood-filled plastic compounds. Unlike extrusion, the primary method by which wood-plastic composite (WPC) parts are made, injection molding is a non-continuous process for manufacturing one or two parts at a time.

A standard Battenfeld TM machine with 2,100 kN of clamping force was used to study the processing behavior of a polypropylene compound with 85% wood-fibre content. Among other things, the project found that plasticizing PP-wood compounds requires narrow tolerances in the control of temperature, screw speed, back pressure and other parameters. One common problem was the segregation of wood and plastic along the flow path, which produced unacceptable parts. High melt temperatures can improve flow, but risk thermal damage to the wood content. Battenfeld plans to focus on melt conditions and homogenization properties in future product development, with the aim of reducing the shear heat generated.

Battenfeld Canada Ltd. 905-670-9384

Flexibility offered in Freedom Series

The HPM Division of Taylor’s Industrial Services has added production flexibility to its Freedom Series by offering an electric screw drive option. The Freedom Hybrid machine suits customers who want a smaller footprint with the same clamping force and durability previous Freedom lines offered. Molders will realize a 30% energy saving compared to the same size non-hybrid Freedom machine, too. The Hybrid also offers reduced machine noise and is cleaner.

CN Smith Plastics Machinery Sales Inc. 416-917-3737