Chapters authored
Epoxy Composites for Radiation Shielding
Due to the increase in use of radiation energy in many industrial applications, radiation shielding has become a crucial topic in order to diminish its hazardous effects. Radiation shields can be of various weights depending on the materials from which they are produced and the area in which they are used. In this sense, polymer composites have taken attention by researchers because it is aimed to obtain shields with good processability, sufficient flexibility, low weight, and subsequent performance properties. Epoxy resin is one of the mostly used synthetic polymers as a matrix element in composite material production due to its improving characteristics by means of electrical insulation, chemical resistance, service life, bonding characteristic, and mechanical properties. Besides, epoxies have intermediate radiation shielding characteristics as well. By loading epoxy matrix with fibers and/or fillers having different radiation absorption rates or mechanical resistance properties, multifunctional shields can be produced to serve in numerous applications. This chapter focuses on radiation shielding efficiency of fiber-reinforced epoxy composites and the role of fillers and fiber-based materials on manufacturing of functional radiation shields.
Part of the book: Epoxy-Based Composites
Evaluation of Waste Tag Pins as Fibers in Gypsum Plasters
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.
Part of the book: Fiber-Reinforced Composites - Recent Advances, New Perspectives and Applications [Working title]