|Ph.D Student||Shpasser Dina|
|Subject||Group 4 Organometallic Complexes in the Synthesis|
|Department||Department of Chemistry||Supervisor||Professor Moris Eisen|
|Full Thesis text|
In this research four different a-olefins containing functional groups were co-polymerized with propylene. 10-undencene-1-ol, containing a hydroxyl group protected by either triisobutyl aluminum (TIBA) or tert-butylmethylsilyl chloride (TBDMSCl), 11-chloro-1-undecene, 5-bromopent-1-ene and N-(dec-9-enyl)-2,2,2-trifluoroacetamide.
Three organometallic catalysts were used for the co-polymerizations: rac-Et(Ind)2ZrCl2, [3-C5H4N]C(NSiMe3)2]2TiCl2 and [m-OMeC6H4C(NSiMe3)2]2ZrCl2.
rac-Et(Ind)2ZrCl2 exhibited significantly greater activity for the incorporation of the co-monomer, 10-undecen-1-ol, into co-polymers with propylene than did either of the benzamidinate catalysts [3-C5H4N]C(NSiMe3)2]2TiCl2 and [m-OMeC6H4C(NSiMe3)2]2ZrCl2. The incorporation of the co-monomer 10-undecene-1-ol into the co-polymer with propylene by rac-Et(Ind)2ZrCl2 was greatly influenced by the choice of the protecting group for the oxygen of the co-monomer. TBDMSCl gave higher incorporation percentage than TIBA for the same concentration of the co-monomer in the reaction feed. However, the co-polymers obtained using TBDMSCl had significantly lower molecular weights than the ones obtained using TIBA.
Both homo and co-polymers were obtained with 11-chloro-1-undecene. However, co-polymerization reactions using 5-bromopent-1-ene did not yield any product under similar conditions to those used for 11-chloro-1-undecene. There was a complete inhibition of the polymerization.
Co-polymers of propylene with N-(dec-9-enyl)-2,2,2-trifluoroacetamide were synthesized successfully using rac-Et(Ind)2ZrCl2 as a catalyst. The molecular weights, incorporation percentages and polydispersity of the obtained co-polymers are close to those obtained for the co-polymerizations of 10-undecene-1-ol protected with TIBA using rac-Et(Ind)2ZrCl2. The amide was reduced post-polymerization using sodium hydroxide to give a co-polymer of propylene containing a primary amine.
Membranes were prepared from three of the obtained co-polymers: two co-polymers containing hydroxyl groups (6% and 10% incorporation) and one co-polymer containing Cl groups (7% incorporation). The flux of the membranes prepared was measured using a flat pressure cell (dead end process) at different pressures.
4-[(tert-butoxycarbonyl)amino]-2-hydroxybutanoic acid (Boc amine) was synthesized as a first step in the synthesis of lactide based residues to be attached to the functional groups in the co-polymers obtained with propylene. Boc amine exhibits multiple conformations. The conformations observed are dependant on solvent and temperature. Boc amine was explored via X-ray, NMR, membrane activity assays and DFT calculations. In addition, its behavior was contrasted to three analogs.