Supercritical carbon dioxide-soluble polyhedral oligomeric silsesquioxane (POSS) nanocages and polymer surface modification

Date

2013-01-01

Author

Dilek Hacıhabiboğlu, Çerağ

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

90
views

0
downloads

In this work, a functionalized polyhedral oligomeric silsesquioxane (POSS) has been investigated for its solubility in supercritical carbon dioxide for the first time in literature. POSS nanocages, which can be functionalized with a wide variety of organic substituents, are most commonly studied as nanofillers in polymer nanocomposites and coatings. Solubility of trifluoropropyl PUSS in supercritical carbon dioxide has been determined by cloud-point measurements performed in a high-pressure view cell. At temperature and pressure ranges of 308-323 K and 8.3-14.8 MPa, these fluorinated organic-inorganic hybrid nanocage structures exhibit solubility up to 4.4% by weight, which is promising for green material processing applications using the environmentally benign solvent. Solubility of CO2-philic PUSS decreases with increasing temperature, while the solubility isotherms at two different temperatures converge. Choosing the processing conditions from the performed solubility studies, trifluoropropyl POSS-supercritical carbon dioxide system has been applied in high-pressure surface modification of a high-molecular weight, rigid poly(methyl methacrylate) (PMMA). Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) analysis of the processed PMMA sheet show that the functionalized nanoparticles were deposited on the PMMA surface, forming a uniform coating of POSS aggregates. This work proves that functionalized PUSS with CO2-philic groups can be solubilized in supercritical CO2, which might allow them to be applied in a plethora of materials modification processes using supercritical carbon dioxide.

Subject Keywords

Silica cage, Nanoparticle, Polymer processing, Surface modification , Cloud point

URI

https://hdl.handle.net/11511/38788

Journal

JOURNAL OF SUPERCRITICAL FLUIDS

DOI

https://doi.org/10.1016/j.supflu.2012.10.012

Collections

Department of Chemical Engineering, Article

Suggestions

OpenMETU
Core

Nanocomposites based on recycled poly(ethylene terepthalate) Tolga, Aslı; Yılmazer, Ülkü; Department of Chemical Engineering (2005) In this study, the effects of glycol type, organoclay type and concentration on the final properties of nanocomposites based on recycled poly(ethylene terephthalate) was investigated. For this purpose, first recycled PET was glycolysed and after that unsaturated polyester-montmorillonite nanocomposites were synthesized by using three different types of glycols (i.e. ethylene glycol (EG), propylene glycol (PG) and diethylene glycol (DEG)). As the first step, all the compositions were prepared by Cloisite 30B...
Electrochemical copolymerization of thiophene containing pseudo-polyether cages with pyrrole Cihaner, Atilla; Önal, Ahmet Muhtar (2006-01-01) Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (1). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution contai...
Electrochemical copolymerization of 2-substituted thiophene derivative linked by polyether bridge with thiophene Cihaner, A; Önal, Ahmet Muhtar (2005-09-01) New conducting copolymers have been synthesized via electrochemical oxidation of thiophene (Th) in the presence of monomer bis(2-thienyl)ethyl (1). Cyclic voltammetry (CV) studies showed that the presence of monomer I in the electrolytic solution greatly changes the CV behaviour of the formation of the polythiophene films. It is found that the increasing ratio of I was found to decrease electroactivity of copoly(I-Th). Electrochemical synthesis of copolymer films was achieved via constant potential electrol...
Nanoalumina-supported rhodium(0) nanoparticles as catalyst in hydrogen generation from the methanolysis of ammonia borane Ozhava, Derya; Özkar, Saim (2017-10-01) Rhodium(0) nanoparticles were in situ formed from the reduction of rhodium(II) octanoate and supported on the surface of nanoalumina yielding Rh(0)/nanoAl(2)O(3) which is highly active catalyst in hydrogen generation from the methanolysis of ammonia borane at room temperature. The kinetics of nanoparticle formation can be followed just by monitoring the volume of hydrogen gas evolved from the methanolysis of ammonia borane. The evaluation of the kinetic data gives valuable insights to the slow, continuous n...
Electrochemical synthesis of crowned conducting polymers : nature of radical cations in polymerization and mechanism of conductivity Cihaner, Atilla; Önal, Ahmet Muhtar; Department of Chemistry (2004) Poly(dibenzo-18-crown-6) (Poly(DB18C6)) was synthesized by electrochemical oxidation of dibenzo-18-crown-6 (DB18C6) using a mixture of acetonitrile and dichloromethane as solvent and tetrabutylammonium tetrafluoroborate (TBABF4) or tetrabutylammonium hexafluorophosphate (TBAPF6) as supporting electrolyte. The anodic polymerization of DB18C6 was investigated using in-situ ESR and in-situ UV-VIS spectroscopic techniques. Spectroelectrochemical (SPEL) properties and thermal analysis of the resulting polymers h...

Citation Formats

Ç. Dilek Hacıhabiboğlu, “Supercritical carbon dioxide-soluble polyhedral oligomeric silsesquioxane (POSS) nanocages and polymer surface modification,” JOURNAL OF SUPERCRITICAL FLUIDS, pp. 171–177, 2013, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38788.