Full text
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| Author(s): |
Mayara Conrado Sartori
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Carlos. |
| Institution: | Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT) |
| Defense date: | 2014-04-24 |
| Examining board members: |
Benedito dos Santos Lima Neto;
Wania da Conceição Moreira
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| Advisor: | Benedito dos Santos Lima Neto |
| Abstract | |
The project aimed the complex [RuCl2(PPh3)3] immobilization in carbon nanotubes by the ligand 3-piperidinemethanol to be used in ROMP. So, this work was divided in two parts: study of the complex [RuCl2 (PPh3)2 (pip-3-MeOH)] and its activity in ROMP; (2) complex [RuCl2 (PPh3)3] immobilization and ROMP studies with it. In the first part, the complex was characterized by elemental analysis (CHN), EPR, FT-IR, RMN 31P{1H} and electronic spectroscopy on UV-vis. The results suggest a pentacoordinated complex with cis-positioned chlorides. The ROMP of norbornene in absence and presence of different acids was tested. The best yield was 93,6% ((Mn = 11 x 104 g.mol-1; PDI = 1,8) of poliNBE in reactions of 60 minutes at 50°C in the presence of HCl with a molar ratio [NBE]/[Ru] = 5000 and 5 μL of EDA. By SEM, it was observed that polymers obtained didn\'t showed pores. For DSC analysis, Tg was approximately 36,5°C. In the second part of the work, the obtained compound was characterized by elemental analysis (CHN) and FT-IR. Leaching studies with a Soxhlet system were performed, followed by analysis by atomic absorption spectroscopy. The percentage of leached ruthenium was 26,13%. The SWNT-Ru was used in ROMP of NBE. In 60 minutes reactions in dichloromethane at 50°C with a molar ratio [NBE]/[Ru] = 5000 and 5 μL of EDA, the yield was 72,1%. The polymers with CNTs were analyzed by SEM and also showed no pores. In DSC analysis, an increase in Tg was observed, which was 42,5°C. In attempting to separate the catalyst from the polymer obtained, ROMP in toluene was tested with low (NEB]/[Ru] = 300) and high ([NBE]/[Ru] = 5000) concentrations, with addiction of ethyl vinyl ether to complete the reaction. None of them was successful. An additional experiment was the functionalization of graphite matrix with ruthenium complex. The obtained compound was characterized by elemental analysis (CHN), FT-IR and electronic spectroscopy in the UV-vis region. The results showed that the graphite can be functionalized and is an alternative low-cost matrix for immobilization of ruthenium complexes. (AU) | |
| FAPESP's process: | 12/05608-4 - Ring opening metathesis polymerization of cyclic olefins catalyzed by a ruthenium complex immobilized on carbon nanotube. |
| Grantee: | Mayara Conrado Sartori |
| Support Opportunities: | Scholarships in Brazil - Master |