This article focused on determining the extinction coefficient of polyolefin foams. A combination of experimental and theoretical methods were used to accomplish this goal. Samples differed from each other in terms of thickness, chemical composition, colour, density, and structural characteristics. Fourier transform infrared spectroscopy was used to measure transmittance spectra. Thermal conductivity of the foams was also measured. The researchers concluded that cell size was the primary factor affecting the ...
Microcellular (methylmethacrylate)-(butyl acrylate)-(Methylmethacrylate) triblock copolymer foams were prepared by a foaming process using CO2. CO2 was first dissolved into sheets of the polymer, and then the pressure was released over different time periods, from 2 to 30 minutes. The density, cellular structure, and thermal conductivity of these foams were then investigated. It was determined that the density decreased with increasing depressurization time; however, the density did not change ...
As the world works to combat climate change, focus has turned to reducing energy use. More efficient thermal insulation could drastically reduce the energy use of residential homes. In this paper, the research team focused on reducing the thermal conductivity of polymeric foams. A number of foam samples with varying cell sizes between 90nm and 100um were created, to show that reducing pore size also reduces the thermal conductivity. The ...
The production of closed cell foams has recently advanced as the materials gain interest. The purpose of this study was to use the transient plane source (TPS) method to measure the thermal conductivity of AlSi7 closed cell foams. Results showed that thermal conductivity increased with sample density, and experimental results were higher than the predictions of the theoretical models. Measurements were also carried out on different directions of the samples ...
Synthetic polymers in starch-based polymer formulations improve the thermal and mechanical properties of the compounds. The purpose of this study was to develop and analyze foams containing ethylene-vinyl acetate (EVA) and varying concentrations of corn starch. A Thermal Constants Analyser measured the thermal conductivity of the EVA/starch samples using the transient plane source (TPS) method. Results showed that the thermal conductivity of the blends increased with starch content. The ...