Characterization and Properties of Water-Blown Rigid Polyurethane Foams Reinforced with Silane-Modified Nanosepiolites Functionalized with Graphite

In the present study, a promising flame retardant consisting of 80 wt% silane-modified nanosepiolites functionalized with 20 wt% graphite (SFG) is used to obtain a synergistic effect principally focussed on the thermal stability of water-blown rigid polyurethane (RPU) foams. Density, microcellular structure, thermal stability and thermal conductivity are examined for RPU foams reinforced with different contents of SFG (0, as reference material, 2, 4 and 6 wt%). The sample with 6 wt% SFG presents a slightly thermal stability improvement, although its cellular structure is deteriorated in comparison with the reference material. Furthermore, the influence of SFG particles on chemical reactions during the foaming process is studied by FTIR spectroscopy. The information obtained from the chemical reactions and from isocyanate consumption is used to optimize the formulation of the foam with 6 wt% SFG. Additionally, in order to determine the effects of functionalization on SFG, foams containing only silane-modified nanosepiolites, only graphite, or silane-modified nanosepiolites and graphite added separately are studied here as well. In conclusion, the inclusion of SFG in RPU foams allows the best performance to be achieved.

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Synergistic effect of BN and MWCNT hybrid fillers on thermal conductivity and thermal stability of ultra-high-molecular-weight polyethylene composites with a segregated structure

Journal of Polymer Research ◽

10.1007/s10965-015-0908-y ◽

2016 ◽

Vol 23 (2) ◽

Cited By ~ 34

Author(s):

Peng-Gang Ren ◽

Xiao-Huan Si ◽

Zhen-Feng Sun ◽

Fang Ren ◽

Lu Pei ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Molecular Weight ◽

Synergistic Effect ◽

High Molecular Weight ◽

Hybrid Fillers ◽

Ultra High Molecular Weight ◽

Thermal Stability Of ◽

Segregated Structure ◽

Polyethylene Composites

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Experimental investigation of OH/H2O in H+-irradiated plagioclase: Implications for the thermal stability of water on the lunar surface

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2021.116806 ◽

2021 ◽

Vol 560 ◽

pp. 116806

Author(s):

Xiandi Zeng ◽

Hong Tang ◽

XiongYao Li ◽

Xiaojia Zeng ◽

Wen Yu ◽

...

Keyword(s):

Thermal Stability ◽

Experimental Investigation ◽

Lunar Surface ◽

Stability Of Water ◽

Thermal Stability Of

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Synergistic effect of iron oxide modified carbon nanotubes on the thermal stability of silicone rubber under different atmospheres

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-015-5081-3 ◽

2015 ◽

Vol 123 (2) ◽

pp. 1281-1291 ◽

Cited By ~ 11

Author(s):

Lu Bai ◽

Junping Zheng

Keyword(s):

Carbon Nanotubes ◽

Thermal Stability ◽

Iron Oxide ◽

Synergistic Effect ◽

Silicone Rubber ◽

Modified Carbon Nanotubes ◽

Thermal Stability Of

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Cryogenic thermal insulating and mechanical properties of rigid polyurethane foams blown with hydrofluoroolefin: Effect of perfluoroalkane

Journal of Cellular Plastics ◽

10.1177/0021955x211062633 ◽

2021 ◽

pp. 0021955X2110626

Author(s):

Tae Seok Kim ◽

Yeongbeom Lee ◽

Chul Hyun Hwang ◽

Kwang Ho Song ◽

Woo Nyon Kim

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Thermal Stability ◽

Cell Size ◽

Thermal Insulation ◽

Coefficient Of Thermal Expansion ◽

Lower Surface ◽

Polyurethane Foams ◽

Insulation Material ◽

Pu Foams

The effect of perfluoroalkane (PFA) on the morphology, thermal conductivity, mechanical properties and thermal stability of rigid polyurethane (PU) foams was investigated under ambient and cryogenic conditions. The PU foams were blown with hydrofluorolefin. Morphological results showed that the minimum cell size (153 μm) was observed when the PFA content was 1.0 part per hundred polyols by weight (php). This was due to the lower surface tension of the mixed polyol solution when the PFA content was 1.0 php. The thermal conductivity of PU foams measured under ambient (0.0215 W/mK) and cryogenic (0.0179 W/mK at −100°C) conditions reached a minimum when the PFA content was 1.0 php. The low value of thermal conductivity was a result of the small cell size of the foams. The above results suggest that PFA acted as a nucleating agent to enhanced the thermal insulation properties of PU foams. The compressive and shear strengths of the PU foams did not appreciably change with PFA content at either −170°C or 20°C. However, it shows that the mechanical strengths at −170°C and 20°C for the PU foams meet the specification. Coefficient of thermal expansion, and thermal shock tests of the PU foams showed enough thermal stability for the LNG carrier’s operation temperature. Therefore, it is suggested that the PU foams blown by HFO with the PFA addition can be used as a thermal insulation material for a conventional LNG carrier.

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High partial thermal conductivity of luminescence sites: a crucial factor for reducing the heat-induced lowering of the luminescence efficiency

Journal of Materials Chemistry C ◽

10.1039/d1tc02287c ◽

2021 ◽

Author(s):

Ni Luo ◽

Jing Xu ◽

Xiyue Cheng ◽

ZhenHua Li ◽

Yidong Huang ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Practical Applications ◽

Good Thermal Stability ◽

The Past ◽

Luminescence Efficiency ◽

Thermal Stability Of

The good thermal stability of a phosphor is crucial for its practical applications. Unfortunately, in the past decades, only Gurney-Mott equation was available to describe the relation between the luminescence...

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Rigid Polyurethane Foams Modified with Biochar

Materials ◽

10.3390/ma14195616 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5616

Author(s):

Katarzyna Uram ◽

Maria Kurańska ◽

Jacek Andrzejewski ◽

Aleksander Prociak

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Thermal Insulation ◽

Foam Cells ◽

Polyurethane Foams ◽

Cross Sectional ◽

Rigid Polyurethane Foams ◽

Insulation Materials

This paper presents results of research on the preparation of biochar-modified rigid polyurethane foams that could be successfully used as thermal insulation materials. The biochar was introduced into polyurethane systems in an amount of up to 20 wt.%. As a result, foam cells became elongated in the direction of foam growth and their cross-sectional areas decreased. The filler-containing systems exhibited a reduction in their apparent densities of up to 20% compared to the unfilled system while maintaining a thermal conductivity of 25 mW/m·K. Biochar in rigid polyurethane foams improved their dimensional and thermal stability.

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