Long, Straight Handle Relies on Reinforced PP

To meet the stringent handling and sanitation requirements of the food and pharmaceutical industries, Danish manufacturer HP-Industrial wanted to develop an industrial broom handle that would eliminate areas where bacteria could potentially develop. The design called for a one-piece broom handle with no joints or seams, and a surface that was smooth and completely sealed. In addition, the handle required strength and rigidity, plus chemical and heat resistance.

To meet these requirements, compounder RTP Company recommended an RTP 100 Series long glass-fibre reinforced polypropylene compound with a flow enhancement package. Using long glass fibres, both the modulus and impact properties are increased, making the PP compound suitably strong for this project.

An injection mold with a 200 cm x 3.2 cm flow length was used to mold the handle, and an internal core was used to achieve a consistent 2 mm wall thickness throughout.

Processing adjustments provided a smooth surface. According to HP’s Niels Sorensen, “The surface finish is equal to that of unfilled resin; there is no visible evidence of the reinforcing fillers.” He adds, “Our handles are perfectly straight when ejected from the mold without any warp and almost without shrinkage.”

RTP Company 800-433-4787