Seasonal investigation of marine litter on beaches of Urla (Izmir/Turkey)

In this study, types and quantities of marine litter in Urla (İzmir) Kum Denizi Beach and Demircili Koyu Beach were determined seasonally between October 2017 and October 2018. At the beaches, marine litter larger than 2,5 centimetres were collected with 3 people along 2-meter lines, which are determined to be parallel to the sea. The collected litters were classified according to the United Nations Environment Program (UNEP, 2009), quantities were determined and the pollution status of the beaches was evaluated according to the Clean Coast Index. A total of 1,265 litter from Kum Denizi Beach and 2,099 litter from Demircili Koyu Beach were collected. In total, 3,364 pieces of litter weighing 90.81 kg were collected from the two beaches. Among the litters collected, plastic litter was found to be dominant with 2,794 pieces. This was followed by 145 metals, 141 papers, 110 fabrics, 87 foam plastics, 42 wood, 32 glass, 8 other litters and 5 rubber. Given the seasonal averages of the clean coast index values; Kum Denizi Beach was found to be clean and Demircili Koyu Beach was found to be moderately polluted.

Sound Absorption Properties of Materials Based on Recycled Plastic Granule Mixtures

This article reports on impedance tube measurements of the sound absorption coefficient α (-) of selected recycled foam plastics, i.e., ethylene-vinyl acetate (EVA), polyvinyl chloride (PVC), polystyrene (PS), and polypropylene (PP), in different mixtures with a binding adhesive. The effect of the thickness of the sample on the sound absorption spectrum as well as the variability in absorption across the different samples of the same composition and thickness are discussed. For the EVA/ PP and PS/PP mixtures, the spectrum is characterized by two peaks that shift as the thickness is changing. These mixtures were also found to be the most absorbent across the whole audible frequency range.

Experimental Study on the Mitigation Effect of Polyurethane Foam Densities on the Cylindrical Objects Entering Water at High Velocity

Polyurethane foam has the properties of energy absorption and mitigating the impact, it has been used in internal protection head cap of cylindrical objects as cushion material, its theory and simulation has been widely discussed by the domestic and foreign scholars, but little experimental research is involved. In this paper, a dynamic loading water-entry impact experiment was designed for polyurethane foam plastics with different densities. In addition, ANSYS/LS-DYNA finite element analysis software was used to simulate water-entry process of cushion materials with different densities. The experimental and simulation results show that the 0.18 g/cm3 polyurethane material can effectively protect the cylindrical head, reduce the stress and have a good cushion effect on it.

Monitoring of Selected Physical and Thermal Properties of Lightweight Concrete Based on Recycled Foam Plastics

This paper aims to verify the use of recycled foam plastics to produce lightweight concrete. Two types of recycled foam plastics (ethyl vinyl acetate and cable insulator) and their mixture in ratios 3:1, 1:1 and 1:3 were used as filler. An organic-based adhesive, Conipur 360, was used as a binder. The evaluation method included verify one of basic physical properties – bulk density. At the same time, thermal properties and strength characteristics of the samples were monitored.

Influence of chemical additives on the properties of polymer foams

Products based on thermosetting plastics have a variety of applications. One of the directions is thermal insulation. Filling foams provide excellent thermal insulation, due to the most optimal ratio of weight, strength and durability. Such heat-insulating materials work in a wide range of operating conditions. The article presents data on the study of the effect of chemical additives on the reduction of the acid number and the reduction in the corrosivity of foam plastics. The greatest efficiency in reducing corrosion activity has composition based on dihydrate of stannous chloride (II) with calcium oxide in a ratio of 2: 0.5. The data on the change in the multiplicity of foaming when introducing chemical additives containing the same name cation and an anion of the same name are presented.