Zhao Chunxu, Chen Xiaohan, Chen Xian
Room 602, Yifu Science and Technology Building, Wangjiang Campus, Sichuan University, Chengdu 610065, China.
Polymers (Basel). 2022 Apr 20;14(9):1654. doi: 10.3390/polym14091654.
In this work, we prepared thermoplastic silicone rubber (TPSiV) by dynamically vulcanizing different relative proportions of methyl vinyl silicone rubber (MVSR), styrene ethylene butene styrene block copolymer (SEBS), and styrene butadiene styrene block copolymer (SBS). The compatibility and distribution of the MVSR phase and SEBS/SBS phase were qualitatively characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) tests on TPSiV. Subsequently, the backscattered electron signal image was analyzed using a colorimeter, and it was found that the size of the interface layer between the MVSR phase and the SEBS-SBS phase could be quantitatively characterized. This method overcomes the defect of the etching method, which cannot quantitatively analyze the size of the compatible layer between the two polymers. The final experiment proved that the two phases in TPSiV exhibited a "sea-island" structure, in which the MVSR phase acted as a dispersed phase in the SEBS-SBS phase. In addition, the addition of the silane coupling agent KH-907 (γ-isocyanatopropyltriethoxysilane) improved the mechanical properties of TPSiV, increasing the tensile strength by about 40% and the elongation at break by 30%. The permanent tensile deformation increase rate was about 15%. Through the quantitative measurement of the compatible layer, it was found that KH-907 could increase the thickness of the interface layer between the MVSR phase and the SEBS-SBS phase by more than 30%, which explained why the silane coupling agent KH-907 improved the mechanical properties of TPSiV at the micro level.
在本工作中，我们通过动态硫化不同相对比例的甲基乙烯基硅橡胶（MVSR）、苯乙烯-乙烯-丁烯-苯乙烯嵌段共聚物（SEBS）和苯乙烯-丁二烯-苯乙烯嵌段共聚物（SBS）制备了热塑性硅橡胶（TPSiV）。通过对TPSiV进行傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）测试，对MVSR相和SEBS/SBS相的相容性和分布进行了定性表征。随后，使用色度计分析背散射电子信号图像，发现可以对MVSR相和SEBS-SBS相之间的界面层尺寸进行定量表征。该方法克服了蚀刻法无法定量分析两种聚合物之间相容层尺寸的缺陷。最终实验证明，TPSiV中的两相呈现“海岛”结构，其中MVSR相在SEBS-SBS相中作为分散相。此外，添加硅烷偶联剂KH-907（γ-异氰酸酯基丙基三乙氧基硅烷）改善了TPSiV的力学性能，拉伸强度提高了约40%，断裂伸长率提高了30%。永久拉伸变形增加率约为15%。通过对相容层的定量测量发现，KH-907可使MVSR相和SEBS-SBS相之间的界面层厚度增加30%以上，这从微观层面解释了硅烷偶联剂KH-907改善TPSiV力学性能的原因。
