Evaluation of Waste Tag Pins as Fibers in Gypsum Plasters

Abstract

This study deals with the usability of tag pins on gypsum-based products, which are used to attach tags on goods such as textile products. The primary motivation of the study is that the tag pins become waste after the sale of the product and this waste is generally produced from polypropylene (PP), which is also used in fiber production. The study used waste tag pins in three different lengths (0.5, 1.0, and 1.5 mm) and at three different fiber volumes such as 5, 10, and 15%. Thus, 40 × 40 × 160 mm sized prismatic gypsum samples were produced and unit weight, ultrasonic pulse velocity (UPV), thermal conductivity, apparent porosity, water absorption, capillary water absorption, compressive and flexural strength of samples were tested. Samples with fiber content exhibited higher flexural strength than the reference sample. The use of longer fibers increased the flexural strength. As a result, the use of tag pins in gypsum matrix generally improved the pore structure and slightly increased the unit weight while enhancing properties such as porosity and water absorption. The same improvement was valid for the mechanical properties. However, the thermal insulation properties of gypsum-based products were adversely affected.