Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 11, 2022 - September 14, 2022
The increase of plastic waste disposed in the environment is a great concern. It is known that these plastic products are fragmented smaller pieces resulting the microplastics (MPs) are generated. In order to study the effects of MPs on living organisms and human immune system, it is necessary to provide MPs for biological tests guaranteed the morphology and size. This study aimed to adjust the geometric shape of MPs by using MP manufacturing systems for environmental fragmentation mechanisms. The proposed system was a pin-on-disc machine with multi-directional sliding motions. Pin made of plastic material was pressed onto a quartz glass disc under the lubrication of artificial sea water. Three types of microtextured glass were prepared and used for elucidating the influence of MP generation. The wear modes of polymer seemed to be affected by convex structures on glass and the material properties of polymer. For the pin made of PVC, which is an amorphous plastic, the production of MPs increased by a larger diameter of the convex structures. The larger diameter increased apparent contact area between the pin and disc, so adhesive wear mode might be predominant. For the pin made of PE, PP and PET, which is crystalline plastic, the production of MPs increased by a larger pitch of the convex structures. The larger pitch enhanced the plastic deformation of plastic into a valley structure, so that fatigue wear might be predominant.
