Supercritical Fluid Microcellular Foaming of High-Hardness TPU via a Pressure-Quenching Process: Restricted Foam Expansion Controlled by Matrix Modulus and Thermal Degradation
机构：[1]Sun Yat sen Univ, Sch Mat Sci & Engn, Guangzhou 510275, Peoples R China[2]Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Ningbo Key Lab Polymer Mat, Ningbo 315201, Peoples R China[3]Univ Chinese Acad Sci, Beijing 100049, Peoples R China
High-hardness thermoplastic polyurethane (HD-TPU) presents a high matrix modulus, low-temperature durability, and remarkable abrasion resistance, and has been used in many advanced applications. However, the fabrication of microcellular HD-TPU foam is rarely reported in the literature. In this study, the foaming behavior of HD-TPU with a hardness of 75D was investigated via a pressure-quenching foaming process using CO2 as a blowing agent. Microcellular HD-TPU foam with a maximum expansion ratio of 3.9-fold, a cell size of 25.9 mu m, and cell density of 7.8 x 10(8) cells/cm(3) was prepared, where a high optimum foaming temperature of about 170 degrees C had to be applied with the aim of softening the polymer's matrix modulus. However, the foaming behavior of HD-TPU deteriorated when the foaming temperature further increased to 180 degrees C, characterized by the presence of coalesced cells, microcracks, and a high foam density of 1.0 g/cm(3) even though the crystal domains still existed within the matrix. The cell morphology evolution of HD-TPU foam was investigated by adjusting the saturation time, and an obvious degradation occurred during the high-temperature saturation process. A cell growth mechanism of HD-TPU foams in degradation environments was proposed to explain this phenomenon based on the gas escape through the defective matrix.
基金：
National Natural Science Foundation of China; Fundamental Research Funds for the Central Universities; [51873226]; [52173053]; [20lgzd02]
第一作者机构：[1]Sun Yat sen Univ, Sch Mat Sci & Engn, Guangzhou 510275, Peoples R China
通讯作者：
通讯机构：[1]Sun Yat sen Univ, Sch Mat Sci & Engn, Guangzhou 510275, Peoples R China[*1]Sun Yat sen Univ, Sch Mat Sci & Engn, Guangzhou 510275, Peoples R China
推荐引用方式(GB/T 7714)：
Chen Bichi,Jiang Junjie,Li Yaozong,et al.Supercritical Fluid Microcellular Foaming of High-Hardness TPU via a Pressure-Quenching Process: Restricted Foam Expansion Controlled by Matrix Modulus and Thermal Degradation[J].MOLECULES.2022,27(24):8911.doi:10.3390/molecules27248911.
APA：
Chen, Bichi,Jiang, Junjie,Li, Yaozong,Zhou, Mengnan,Wang, Zelin...&Zhai, Wentao.(2022).Supercritical Fluid Microcellular Foaming of High-Hardness TPU via a Pressure-Quenching Process: Restricted Foam Expansion Controlled by Matrix Modulus and Thermal Degradation.MOLECULES,27,(24)
MLA：
Chen, Bichi,et al."Supercritical Fluid Microcellular Foaming of High-Hardness TPU via a Pressure-Quenching Process: Restricted Foam Expansion Controlled by Matrix Modulus and Thermal Degradation".MOLECULES 27..24(2022)
