The Influence of New Hydrophobic Silica Nanoparticles on the Surface Properties of the Films Obtained from Bilayer Hybrids.
Ultra-hydrophobic bilayer coatings on a glass surface were fabricated by sol-gel process using hexadecyltrimethoxysilane (C16TMS) and tetramethoxysilane (TMOS) (1:4 molar ratio) as precursors. After coating, silica nanoparticles (SiO₂ NPs) functionalized with different mono-alkoxy derivatives (methoxytrimethylsilane, TMeMS; ethoxydimethylvinylsilane, DMeVES; ethoxydimethylphenylsilane, DMePhES; and methoxydimethyloctylsilane, DMeC₈MS) were added, assuring the microscale roughness on the glass surface. Influences of the functionalized SiO₂ NPs and surface morphology on the hydrophobicity of the hybrid films were discussed. The successful functionalization of SiO₂ NPs with hydrophobic alkyl groups were confirmed by Fourier transform infrared spectroscopy (FTIR). The thermal stability of hydrophobic SiO₂ NPs showed that the degradation of the alkyl groups takes place in the 200-400 °C range. Bilayer coating with C16TMS/TMOS and SiO₂ NPs modified with alkoxysilane substituted with C₈ alkyl chain (SiO₂ NP-C₈) has micro/nano structure. Hydrophobicity of functionalized SiO₂ NPs-C₈ and its higher degree of nanometer-scale roughness gave rise to ultra-hydrophobicity performance for bilayer coating C16TMS/TMOS + SiO₂ NPs-C₈ (145°), compared to other similar hybrid structures. Our synthesis method for the functionalization of SiO₂ NPs is useful for the modification of surface polarity and roughness.
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. cpetcu@icf.ro.
Cristian
C
Petcu
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. violetapurcar@yahoo.com.
Violeta
V
Purcar
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. spataru.catalin@gmail.com.
Cătălin-Ilie
CI
Spătaru
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. elviraalexandrescu@yahoo.com.
Elvira
E
Alexandrescu
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. r.somoghi@gmail.com.
Raluca
R
Şomoghi
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. trica.bogdan@gmail.com.
Bogdan
B
Trică
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. sabina.nitu@yahoo.com.
Sabina Georgiana
SG
Niţu
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. panaitescu@icf.ro.
Denis Mihaela
DM
Panaitescu
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. ddonescu@chimfiz.icf.ro.
Dan
D
Donescu
R & D National Institute for Chemistry and Petrochemistry-ICECHIM, Polymers Department, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania. jecu.luiza@icechim.ro.
Maria-Luiza
ML
Jecu
nanostructuration; organic–inorganic hybrids; silica nanoparticles; sol–gel process; trialkylmonoalkoxysilanes