Phosphorylated silica nanotubes: preparation and characterization

Abstract

Recently, the strategy of doping inorganic particles into polymer membranes to modify them has been studied intensively. However, these inorganic particles have a disadvantage without being in good compatibility with the polymers. To enhance the compatibility between inorganic particles and polymers, phosphorylated silica nanotubes (PSNTs) with specific high ratios of length to diameter are prepared. Silica nanotubes (SNTs) are prepared through the hydrolysis of tetraethyl orthosilicate in a mixture of aqueous ammonia and dl-tartaric acid, then PSNTs are obtained by silylation and phosphorylation modifications. The optimum synthesis conditions of PSNTs are explored; in addition, the as-prepared PSNTs are characterized by Fourier transform infrared, transmission electron microscope, BET, x-ray photoelectron spectroscopy analysis and thermogravimetric analysis. The results indicate that the ratio of length to diameter of the PSNTs is approximately 20, the thickness of the tube wall is 20 nm, the specific surface area of the PSNTs is 460.2 m(2) g(-1), the inner diameter of the PSNTs is 76 nm, many mesopores are distributed in the tube walls of the PSNTs, and the PSNTs have numerous hydroxyl active sites along their length direction. Therefore, PSNTs are desirable as suitable fillers of polymer membranes.

Preparation and characterization of sulfonated poly(arylene thioether sulfone)/imino-containing phosphorylated silica particle composite proton exchange membranes

“…The weight loss of Si-imP at 320°C to 700°C is far greater than that of SiO 2 , which is mainly caused by thermal decomposition of aminopropyl and other organic components. 35 The above results indicate that Si-imP was successfully prepared.…”

Polysulfone(PSF) composite membrane with micro-reaction locations (MRLs) made by doping sulfated TiO 2 deposited on SiO 2 nanotubes (STSNs) for cleaning wastewater

“…Considering the above problems, Zhang et al synthesized phosphorylated silica nanotubes (PSNTs) as a better filling material to modify PVDF membranes [13], which took the advantages of silica nanotubes (SNTs) with hollow structures, high specific surface areas, high ratio of length to diameter, biocompatibility and good anti-compaction strength etc [14]. The results showed that in the length direction of PSNTs, there are many accessible active sites to be compatible with the polymer membrane along the direction of polymer chains; in the diameter direction of PSNTs, there is a unique circular wall with nanometer thickness, which can function as a new energy dissipation approach to resist the outer impact forces.…”

Controlled‐release drug carriers based hierarchical silica microtubes templated from cellulose acetate nanofibers

“…Owing to their low density, large void space, and specific surface area, HMMs are promising in various applications, such as adsorption and storage, confined catalysis, optical devices, enzyme immobilization, etc. [18][19][20][21] For example, an amphiphilic block copolymer 22 and a mixture of aqueous ammonia and tartaric acid 23 were used for softtemplating hollow mesoporous silica nanoparticles with tunable shell thickness and pore size and phosphorylated silica nano-tubes with high length-to-diameter ratios, respectively. 4,[6][7][8][9][10][11][12][13][14][15][16][17] A template-directed synthesis strategy is an ideal tool to fabricate hollow materials because the resultant physical dimensions can be precisely controlled and monodisperse samples can be harvested in large quantity.…”

“…In general, there are two main synthetic routes to produce HMMs, soft-and hard-templating. [18][19][20][21] For example, an amphiphilic block copolymer 22 and a mixture of aqueous ammonia and tartaric acid 23 were used for softtemplating hollow mesoporous silica nanoparticles with tunable shell thickness and pore size and phosphorylated silica nano-tubes with high length-to-diameter ratios, respectively. Silicate hollow nanotubes were synthesized via hard-templating by replicating carbon nanotubes via a sol-gel process with heat treatment.…”