With the increasing number of printable materials, one area in particular is seeing a lot of growth: green-based filaments. From peat to hemp, there’s been a surge in “natural” filaments that are recyclable and often reusable. Now joining this illustrious list of naturally-derived materials is bamboo, used to add material characteristics to PP. Researchers developed a composite material from plastics and bamboo, using bamboo powders and polypropylene and tested changes in its melt flow rate, softening point, impact strength and tensile strength.
Bamboo is a great material to use for this type of materials research. As a natural material, it displays great tensile strength, toughness and hardness. It even beats out tree bark and wood in those particular categories. It’s also not the first time researchers and developers have experimented with it as a filament, although this time around, the research is more interested in measuring its abilities as an enhancing material in conjunction with plastics.
Bamboo & Plastic Composites
Before they could make the compound, the researchers dried the bamboo powder and mixed it with an aluminate coupling agent and a “compatibilizer”. They then mixed this output with the polypropylene matrix at high speeds. The researchers finalised a compound material by heating and plasticizing both ingredients using a twin-screw extruder. Next, they created composite parts with the extrusion process and injection molding.
“The modification of bamboo fiber by microorganisms, or the modification of fiber surface by bamboo fiber through maleic anhydride grafting, silane coupling, etc. is intended to improve the compatibility of fiber with plastic matrix,” the researchers clarified. “Add inorganic micro-nanoparticles or add binder to modify the mechanical properties of the material.”
The researchers then measured the various characteristics of the material using an electron microscope. They found that the melt index of the composite decreases with the increase of bamboo-plastic ratio. However, it increases the heat resistance of the composite overall. It also improves impact strength while decreasing tensile strength.
All in all, the composite shows great promise for the future of plastic filaments. Mixtures such as this could provide novel and sustainable alternatives to traditional filament production techniques.
Featured image courtesy of the researchers. Retrieved via the paper: ‘Preparation and Properties of Polypropylene Composites Reinforced by Modified Phyllostachys pubescens Fibers’.