Thermal conductivity analysis of a new sub-micron sized polystyrene foam

Abstract

New polystyrene (PS) foams with submicron pore sizes and open pore structure are introduced as potential cores for vacuum insulation panels (VIPs). Measurements of the thermal conductivity λ of the air-filled and evacuated PS foams, the influence of temperature T, opacifiers as well as gas pressure p on the thermal conductivity λ are presented. First results of the foam microstructures, as visualized by electron microscopy, confirm that pore sizes below 1 µm can be achieved. Thermal conductivity values of advanced samples in vacuum of about 7 mW/(m·K) were measured.

Effect of Nano Titanium Oxide with Different Surface Treatments on Color Stability of Red-Tinted Silicone Rubber

“…The statistical results from Table 1 to Table 4 show that in the test pieces with the same thickness of 1 mm and four concentrations (0, 0.05%, 0.10%, and 0.15%) of silicon aluminum-coated nano-TiO 2 coating, Δ E , Δ L ∗ , Δ a ∗ , Δ b ∗ gradually decrease with the increase of the concentration of silicon aluminum-coated nano-TiO 2 , reach the lowest in the 0.1% group, and then increase in the 0.15% group [ 15 ], i.e., Δ E , Δ L ∗ , Δ a ∗ , Δ b ∗ decreased first and then increased with the increase of the concentration of silicon aluminum-coated nano-TiO 2 film. There was a significant difference in the total color difference Δ E among the samples with different silicon aluminum-coated nano-TiO 2 concentration silicone rubber cover film of 1 mm thickness ( P < 0.05).…”

Preparing low-Density microcellular polystyrene foam by in-Situ fibrillated PTFE and supramolecular nucleator TMC-300 in the presence of sc-CO2

“…Next, a water displacement technique (ASTM D792-00) was used to measure foam density. According to this study, cell density was computed by equations ( 1) and (2).…”

“…Polystyrene (PS) foams, as a kind of lightweight material, has been widely applied in construction, insulation, packaging, sports facilities, and transportation. [1][2][3][4] Therefore, it also has a significant market share in the foam market. In addition, since PS is recyclable, its waste minimizing property makes research on PS foam materials essential.…”

Microcellular foams production from nanocomposites based on PS using MOF nanoparticles with enhanced CO2 properties as nucleating agent

“…5,7 Besides, cell size reduction allows reducing the thermal conductivity. According to Knudsen effect, [8][9][10] cell sizes below the mean free path of the molecules which are inside the cells, promotes the decrease of collisions between them and then the thermal conductivity associated to the gas phase.…”