Rajabimashhadi Zahra, Naghizadeh Rahim, Zolriasatein Ashkan, Bagheri Sonia, Mele Claudio, Esposito Corcione Carola
School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran.
Non-Metallic Materials Research Department, Niroo Research Institute, Tehran 1466-5517, Iran.
Polymers (Basel). 2023 Apr 17;15(8):1916. doi: 10.3390/polym15081916.
Polyurethane (PU) is one of the most well-known polymer coatings because of its favorable characteristics, which include its low density, nontoxicity, nonflammability, longevity, adhesion, simple manufacture, flexibility, and hardness. However, PU does come with several major drawbacks, among which are poor mechanical properties as well as low thermal and chemical stability, particularly in the high-temperature mode, where becomes gets flammable and loses adhesion ability. The limitations have inspired researchers to develop a PU composite to improve the weaknesses by adding different reinforcements. Magnesium hydroxide, having the ability to be produced with exceptional properties such as flammability, has consistently attracted the interest of researchers. Additionally, silica nanoparticles with high strength and hardness are one of the excellent reinforcements of polymers these days. The hydrophobic, physical, and mechanical properties of pure polyurethane and the composite type (nano, micro, and hybrid) fabricated with the drop casting method were examined in this study. 3-Aminopropyl triethoxysilane was applied as a functionalized agent. To confirm that hydrophilic particles turned into hydrophobic, FTIR analysis was carried out. The impact of size, percentage, and kind of fillers on different properties of PU/Mg(OH)2-SiO2 was then investigated using different analyses including spectroscopy and mechanical and hydrophobicity tests. The resultant observations demonstrated that different surface topographies can be obtained from the presence of particles of different sizes and percentages on the hybrid composite's surface. Surface roughness allowed for exceptionally high water contact angles, which confirmed the hybrid polymer coatings' superhydrophobic properties. According to the particle size and content, the distribution of fillers in the matrix also improved the mechanical properties.
聚氨酯（PU）是最知名的聚合物涂层之一，因其具有低密度、无毒、不燃、寿命长、附着力强、制造简单、柔韧性好和硬度高等良好特性。然而，PU也存在几个主要缺点，其中包括机械性能差以及热稳定性和化学稳定性低，特别是在高温模式下，此时它会变得易燃并失去附着力。这些局限性促使研究人员开发一种PU复合材料，通过添加不同的增强材料来改善这些弱点。氢氧化镁具有诸如阻燃性等优异性能，一直吸引着研究人员的关注。此外，具有高强度和硬度的二氧化硅纳米颗粒是当今聚合物的优秀增强材料之一。本研究考察了纯聚氨酯以及采用滴铸法制备的复合材料类型（纳米、微米和杂化）的疏水、物理和机械性能。使用3-氨丙基三乙氧基硅烷作为功能化剂。为了确认亲水性颗粒变成了疏水性颗粒，进行了傅里叶变换红外光谱（FTIR）分析。然后使用包括光谱学、机械和疏水性测试在内的不同分析方法，研究了填料的尺寸、百分比和种类对PU/Mg(OH)₂-SiO₂不同性能的影响。所得观察结果表明，在杂化复合材料表面存在不同尺寸和百分比的颗粒可获得不同的表面形貌。表面粗糙度使得水接触角异常高，这证实了杂化聚合物涂层的超疏水性能。根据颗粒尺寸和含量，填料在基体中的分布也改善了机械性能。
