Article
Polymer Science
Ehsan Rostami-Tapeh-Esmaeil, Sahar Shojaei, Denis Rodrigue
Summary: Uniform and graded polyolefin elastomer (POE) foams were prepared using a single-step technology, and the effects of molding temperature on the foams' morphology, mechanical properties, and thermal conductivity were investigated. The results showed that the foam's properties can be easily controlled by the cellular structure, and graded samples are more interesting for thermal insulation applications.
Article
Polymer Science
Yue Tian, Yinfu Luo, Haichao Meng, Long Ni, Cuiqing Zhou, Shengtai Zhou, Huawei Zou, Mei Liang
Summary: Lightweight polyimide foams (PIFs) with exceptional thermal resistance and compressive properties are fabricated by heating polyester ammonium salts (PEASs) prepared by copolymerizing 4, 4'-diaminobenzanilide (DABA), 4, 4'-diaminodiphenyl methane (MDA), and 3, 3', 4, 4'-benzophenone tetracarboxylic dianhydride (BTDA). The addition of DABA forms hydrogen bonds between CONH and C=O in the PI chains, increasing the melt viscosity of PEAS precursors and promoting the expansion of cells.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Polymer Science
Haichao Meng, Long Ni, Cuiqing Zhou, Chen Qiu, Yinfu Luo, Huawei Zou, Shengtai Zhou, Mei Liang
Summary: Rigid polyimide foams (PIFs) with good mechanical properties and thermal resistance were successfully fabricated through thermal foaming of polyester ammonium salt precursors with the addition of a pararosaniline base as a crosslinker. The crosslinked structure derived from the base improved melt viscosity and provided sufficient strength to prevent shrinkage, leading to enhanced compressive properties. The PIFs exhibited a 6.6 to 7.9 times increase in compressive strength compared to regular polyimide foams, and their thermal properties were also excellent.
Article
Polymer Science
Branka Music, Natasa Knez, Janez Bernard
Summary: This study investigates the influence of two flame retardants on polyurethane foam (PUR) systems, focusing on their thermal and mechanical properties. The results show that the flame retardants significantly improve the fire resistance of the PUR systems without affecting thermal conductivity, and only slightly decreasing the mechanical properties. These findings suggest that the presented systems can be applied as thermal insulation where both low heat conductivity and high flame resistance are required.
Article
Mechanics
Bo -Yuan Su, Wen -Yea Jang
Summary: The present study investigated the microstructure and compressive response of ALPORAS closed-cell foam. Micro-CT technique and image processing algorithms were used to analyze the foam's interior structure and measure its geometrical characteristics. Three statistical measurements were employed to develop numerical models, and the effects of different parameters on the models' characteristics were examined. Numerical simulations were conducted and compared with experimental results, showing a discrepancy attributed to differences in microstructural features.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Chemistry, Multidisciplinary
Ni Komang Ayu Agustini, Andreas Triwiyono, Djoko Sulistyo, S. Suyitno
Summary: This study demonstrates that the addition of PP fibers increases the strength and tensile strength of foamed geopolymer, while the content of PP fibers significantly affects the thermal conductivity of foamed geopolymer. The thermal conductivity of foamed geopolymer in this study is similar to lightweight concrete and slightly higher than gypsum board.
APPLIED SCIENCES-BASEL
(2021)
Article
Polymer Science
Junyu Yang, Aaron Shen, Sachin S. Velankar
Summary: PPEK is an amorphous thermoplastic polymer with a high glass transition temperature, and foam preparation using a foaming agent allows for the production of foams with varying densities. The thermal conductivity and modulus of the foams decrease with density, following expected trends from existing models. The foams exhibit stability at high temperatures, suggesting potential applications in structural or insulation settings.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
Article
Polymer Science
Simona Losio, Angelica Cifarelli, Adriano Vignali, Simona Tomaselli, Fabio Bertini
Summary: In this study, bio-polyols with high hydroxyl number, narrow polydispersity index, and low molecular mass were synthesized from partially and completely epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid. These bio-polyols were used to produce polyurethane foams, which showed superior mechanical properties compared to reference foams. The novel synthesized polyurethane materials could be potential replacements for petroleum-based materials.
Article
Polymer Science
Long Ni, Yinfu Luo, Xionghou Peng, Shengtai Zhou, Huawei Zou, Mei Liang
Summary: Polyimide foam has been utilized as structural and thermal insulation materials due to its nearly homogeneous spherical closed pore structure and outstanding thermal stability. The prepared foam shows extremely low thermal conductivity and thermal diffusivity, which makes it ideal for applications in high-tech fields such as aerospace, marine transportation, and microelectronics.
Article
Nanoscience & Nanotechnology
Kazue Orikasa, Tyler Dolmetsch, Lihua Lou, Tony Thomas, Benjamin Boesl, Arvind Agarwal
Summary: In this study, ultralight boron nitride nanoplatelet (BNNP) foams were fabricated via freeze-drying, and their highly anisotropic thermal and mechanical properties were characterized. The study also established a protocol for designing 2D material foams with tailorable properties for thermal management applications.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Ceramics
Majda Pavlin, Barbara Horvat, Mark Cesnovar, Vilma Ducman
Summary: In this study, the potential use of waste mineral wool for the production of alkali-activated foams was evaluated. The results showed that waste stone wool can be used as a precursor for the production of porous foams with different densities and mechanical properties.
CERAMICS INTERNATIONAL
(2022)
Article
Thermodynamics
Francesco Galvagnini, Andrea Dorigato, Francesco Valentini, Vincenzo Fiore, Maria La Gennusa, Alessandro Pegoretti
Summary: In this work, polyurethane insulating panels containing microencapsulated paraffin as phase change material (PCM) were produced. The panels exhibited thermal insulation and energy storage/releasing properties near room temperature. The addition of the microcapsules increased the viscosity of the PU liquid precursors and affected the cellular structure of the PU foams. The introduction of the PCM improved the thermal and mechanical properties of the foams, while increasing their thermal conductivity and stiffness.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
Xiaokun Chen, Wencong Yu, Li Ma, Shasha Zhou, Xixi Liu
Summary: Phenolic foam (PF) exhibits excellent fire resistance and thermal insulation properties. Increasing density improves cell hole sealing and compressive strength, but decreases insulation effect. Chemical structure is not affected by density, but physical properties are influenced by density variations.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Engineering, Multidisciplinary
Balint Morlin, Katalin Litauszki, Roland Petreny, Akos Kmetty, Laszl Meszaros
Summary: This research found that the presence of nanoparticles, especially halloysite, in polymeric foams can increase the specific compressive strength, with the use of 3% halloysite showing the most significant improvement. Additionally, the addition of nanoparticles reduced the standard deviation of this ratio and decreased the average cell diameter compared to the reference material.
Article
Polymer Science
Morgane Massart, Charles Dubois, Marc Boileau
Summary: This study evaluated the effects of alternative plasticizers and nucleating agents on novel celluloid-like formulations, finding that some plasticizers can improve mechanical properties beyond regular celluloid, while the nucleating agents have a clear impact on the microstructure of foamed materials.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
