Surface hydrophobicity: effect of alkyl chain length and network homogeneity
Wenqian Chen1(), Vikram Karde1, Thomas N. H. Cheng1, Siti S. Ramli2, Jerry Y. Y. Heng1
1. Department of Chemical Engineering, Imperial College London, London, SW7 2AZ, UK 2. Department of Food Technology, Faculty of Applied Sciences, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
Understanding the nature of hydrophobicity has fundamental importance in environmental applications. Using spherical silica nanoparticles (diameter= 369 ± 7 nm) as the model material, the current study investigates the relationship between the alkyl chain network and hydrophobicity. Two alkyl silanes with different chain length (triethoxymethylsilane (C1) vs. trimethoxy(octyl)silane (C8)) were utilised separately for the functionalisation of the nanoparticles. Water contact angle and inverse gas chromatography results show that the alkyl chain length is essential for controlling hydrophobicity, as the octyl-functionalised nanoparticles were highly hydrophobic (water contact angle= 150.6° ± 6.6°), whereas the methyl-functionalised nanoparticles were hydrophilic (i.e., water contact angle= 0°, similar to the pristine nanoparticles). The homogeneity of the octyl-chain network also has a significant effect on hydrophobicity, as the water contact angle was reduced significantly from 148.4° ± 3.5° to 30.5° ± 1.0° with a methyl-/octyl-silane mixture (ratio= 160:40 µL·g–1 nanoparticles).
. [J]. Frontiers of Chemical Science and Engineering, 2021, 15(1): 90-98.
Wenqian Chen, Vikram Karde, Thomas N. H. Cheng, Siti S. Ramli, Jerry Y. Y. Heng. Surface hydrophobicity: effect of alkyl chain length and network homogeneity. Front. Chem. Sci. Eng., 2021, 15(1): 90-98.
X Sun, Y Zhang, G Chen, Z Gai. Application of nanoparticles in enhanced oil recovery: a critical review of recent progress. Energies, 2017, 10(3): 345 https://doi.org/10.3390/en10030345
2
A Behzadi, A Mohammadi. Environmentally responsive surface-modified silica nanoparticles for enhanced oil recovery. Journal of Nanoparticle Research, 2016, 18(9): 266 https://doi.org/10.1007/s11051-016-3580-1
3
A U Rognmo, S Heldal, M A Fernø. Silica nanoparticles to stabilize CO2-foam for improved CO2 utilization: enhanced CO2 storage and oil recovery from mature oil reservoirs. Fuel, 2018, 216: 621–626 https://doi.org/10.1016/j.fuel.2017.11.144
4
X Yang, Z Shen, B Zhang, J Yang, W X Hong, Z Zhuang, J Liu. Silica nanoparticles capture atmospheric lead: implications in the treatment of environmental heavy metal pollution. Chemosphere, 2013, 90(2): 653–656 https://doi.org/10.1016/j.chemosphere.2012.09.033
5
W Stöber, A Fink, E Bohn. Controlled growth of monodisperse silica spheres in the micron size range. Journal of Colloid and Interface Science, 1968, 26(1): 62–69 https://doi.org/10.1016/0021-9797(68)90272-5
6
G H Bogush, M A Tracy, C F Zukoski Iv. Preparation of monodisperse silica particles: control of size and mass fraction. Journal of Non-Crystalline Solids, 1988, 104(1): 95–106 https://doi.org/10.1016/0022-3093(88)90187-1
7
S K Park, K D Kim, H T Kim. Preparation of silica nanoparticles: determination of the optimal synthesis conditions for small and uniform particles. Colloids and Surfaces. A, Physicochemical and Engineering Aspects, 2002, 197(1-3): 7–17 https://doi.org/10.1016/S0927-7757(01)00683-5
8
C A Costa, C A Leite, F Galembeck. Size dependence of Stöber silica nanoparticle microchemistry. Journal of Physical Chemistry B, 2003, 107(20): 4747–4755 https://doi.org/10.1021/jp027525t
9
D L Green, J S Lin, Y F Lam, M C Hu, D W Schaefer, M T Harris. Size, volume fraction, and nucleation of Stober silica nanoparticles. Journal of Colloid and Interface Science, 2003, 266(2): 346–358 https://doi.org/10.1016/S0021-9797(03)00610-6
10
K Nozawa, H Gailhanou, L Raison, P Panizza, H Ushiki, E Sellier, J P Delville, M H Delville. Smart control of monodisperse Stöber silica particles: effect of reactant addition rate on growth process. Langmuir, 2005, 21(4): 1516–1523 https://doi.org/10.1021/la048569r
11
V M Masalov, N S Sukhinina, E A Kudrenko, G A Emelchenko. Mechanism of formation and nanostructure of Stöber silica particles. Nanotechnology, 2011, 22(27): 275718 https://doi.org/10.1088/0957-4484/22/27/275718
12
S Li, Q Wan, Z Qin, Y Fu, Y Gu. Understanding Stöber silica’s pore characteristics measured by gas adsorption. Langmuir, 2015, 31(2): 824–832 https://doi.org/10.1021/la5042103
13
S L Greasley, S J Page, S Sirovica, S Chen, R A Martin, A Riveiro, J V Hanna, A E Porter, J R Jones. Controlling particle size in the Stöber process and incorporation of calcium. Journal of Colloid and Interface Science, 2016, 469: 213–223 https://doi.org/10.1016/j.jcis.2016.01.065
14
A Liberman, N Mendez, W C Trogler, A C Kummel. Synthesis and surface functionalization of silica nanoparticles for nanomedicine. Surface Science Reports, 2014, 69(2-3): 132–158 https://doi.org/10.1016/j.surfrep.2014.07.001
15
H Sawada, T Tashima, Y Nishiyama, M Kikuchi, Y Goto, G Kostov, B Ameduri. Iodine transfer terpolymerization of vinylidene fluoride, α-trifluoromethacrylic acid and hexafluoropropylene for exceptional thermostable fluoropolymers/silica nanocomposites. Macromolecules, 2011, 44(5): 1114–1124 https://doi.org/10.1021/ma102532k
16
M Kobayashi, F Juillerat, P Galletto, P Bowen, M Borkovec. Aggregation and charging of colloidal silica particles: effect of particle size. Langmuir, 2005, 21(13): 5761–5769 https://doi.org/10.1021/la046829z
17
B P Binks, S O Lumsdon. Influence of particle wettability on the type and stability of surfactant-free emulsions. Langmuir, 2000, 16(23): 8622–8631 https://doi.org/10.1021/la000189s
18
R Aveyard, B P Binks, J H Clint. Emulsions stabilised solely by colloidal particles. Advances in Colloid and Interface Science, 2003, 100: 503–546 https://doi.org/10.1016/S0001-8686(02)00069-6
19
H Balard, E Papirer, A Khalfi, H Barthel. Trimethylchlorosilane modified silica surfaces: characterization by inverse gas chromatography using PDMS oligomers as probes. Composite Interfaces, 1998, 6(1): 19–25 https://doi.org/10.1163/156855499X00251
20
V R Ghaleh, A Mohammadi. The stability and surface activity of environmentally responsive surface-modified silica nanoparticles: the importance of hydrophobicity. Journal of Dispersion Science and Technology, 2020, 41(9): 1299–1310
21
B Zhao, L Zhu. Mixed polymer brush-grafted particles: a new class of environmentally responsive nanostructured materials. Macromolecules, 2009, 42(24): 9369–9383 https://doi.org/10.1021/ma902042x
22
Y Wang, D Fan, J He, Y Yang. Silica nanoparticle covered with mixed polymer brushes as Janus particles at water/oil interface. Colloid & Polymer Science, 2011, 289(17-18): 1885–1894 https://doi.org/10.1007/s00396-011-2506-9
23
J Pyun, S Jia, T Kowalewski, G D Patterson, K Matyjaszewski. Synthesis and characterization of organic/inorganic hybrid nanoparticles: kinetics of surface-initiated atom transfer radical polymerization and morphology of hybrid nanoparticle ultrathin films. Macromolecules, 2003, 36(14): 5094–5104 https://doi.org/10.1021/ma034188t
24
A J Worthen, V Tran, K A Cornell, T M Truskett, K P Johnston. Steric stabilization of nanoparticles with grafted low molecular weight ligands in highly concentrated brines including divalent ions. Soft Matter, 2016, 12(7): 2025–2039 https://doi.org/10.1039/C5SM02787J
25
J A Schultz, L Lavielle, C Martin. The role of the interface in carbon fibre-epoxy composites. Journal of Adhesion, 1987, 23(1): 45–60 https://doi.org/10.1080/00218468708080469
26
C Della Volpe, S Siboni. Some reflections on acid-base solid surface free energy theories. Journal of Colloid and Interface Science, 1997, 195(1): 121–136 https://doi.org/10.1006/jcis.1997.5124
27
S C Das, I Larson, D A Morton, P J Stewart. Determination of the polar and total surface energy distributions of particulates by inverse gas chromatography. Langmuir, 2011, 27(2): 521–523 https://doi.org/10.1021/la104135z
28
C J Van Oss, M K Chaudhury, R J Good. Interfacial Lifshitz-van der Waals and polar interactions in macroscopic systems. Chemical Reviews, 1988, 88(6): 927–941 https://doi.org/10.1021/cr00088a006
29
J Y Heng, F Thielmann, D R Williams. The effects of milling on the surface properties of form I paracetamol crystals. Pharmaceutical Research, 2006, 23(8): 1918–1927 https://doi.org/10.1007/s11095-006-9042-1
30
R Ho, J Y Heng. A review of inverse gas chromatography and its development as a tool to characterize anisotropic surface properties of pharmaceutical solids. Kona Powder and Particle Journal, 2013, 30(0): 164–180 https://doi.org/10.14356/kona.2013016
31
V Karde, C Ghoroi. Influence of surface modification on wettability and surface energy characteristics of pharmaceutical excipient powders. International Journal of Pharmaceutics, 2014, 475(1-2): 351–363 https://doi.org/10.1016/j.ijpharm.2014.09.002
32
S Ramanaiah, V Karde, P Venkateswarlu, C Ghoroi. Effect of temperature on the surface free energy and acid-base properties of Gabapentin and Pregabalin drugs—a comparative study. RSC Advances, 2015, 5(60): 48712–48719 https://doi.org/10.1039/C5RA03032C
33
V Karde, C Ghoroi. Fine powder flow under humid environmental conditions from the perspective of surface energy. International Journal of Pharmaceutics, 2015, 485(1-2): 192–201 https://doi.org/10.1016/j.ijpharm.2015.03.021
34
M Jafarzadeh, R Adnan, M K Mazlan. Thermal stability and optical property of ormocers (organically modified ceramics) nanoparticles produced from copolymerization between amino-silanes and tetraethoxysilane. Journal of Non-Crystalline Solids, 2012, 358(22): 2981–2987 https://doi.org/10.1016/j.jnoncrysol.2012.07.028
35
F Wu, B Zhang, W Yang, Z Liu, M Yang. Inorganic silica functionalized with PLLA chains via grafting methods to enhance the melt strength of PLLA/silica nanocomposites. Polymer, 2014, 55(22): 5760–5772 https://doi.org/10.1016/j.polymer.2014.08.070
36
M Sándor, C Nistor, G Szalontai, R Stoica, C Nicolae, E Alexandrescu, J Fazakas, F Oancea, D Donescu. Aminopropyl-silica hybrid particles as supports for humic acids immobilization. Materials (Basel), 2016, 9(1): 34 https://doi.org/10.3390/ma9010034
37
W Yuan, F Wang, Z Chen, C Gao, P Liu, Y Ding, S Zhang, M Yang. Efficient grafting of polypropylene onto silica nanoparticles and the properties of PP/PP-g-SiO2 nanocomposites. Polymer, 2018, 151: 242–249 https://doi.org/10.1016/j.polymer.2018.07.060
