Preparation of "Constrained Geometry" Titanium Complexes of [1,2]Azasilinane Framework for Olefin Polymerization
- 주제(키워드) Copolymerization , Ethylene , Titianium catalyst
- 발행기관 아주대학교
- 지도교수 이분열
- 발행년도 2017
- 학위수여년월 2017. 2
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 실제URI http://www.dcollection.net/handler/ajou/000000024929
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The Me2Si-bridged ansa-Cp/amido half-metallocene, [Me2Si(n5-Me4C5)(NtBu)]TiCl2, termed a "constrained-geometry catalyst (CGC)", is a representative homogeneous Ziegler catalyst. CGC derivatives with the [1,2]azasilinane framework, in which the amide alkyl substituent is joined by the Si-bridge, were prepared, and the catalytic performances of these species was studied. Me4C5H-Si(Me)(CH2CH=CH2)-NH(C(R)(R')CH=CH2) (R, R' = H or methyl; Me4C5H = tetramethylcyclopentadienyl) was susceptible to ring closure metathesis (RCM) when treated with Schrock's Mo-catalyst to afford -Si(Me4C5H)(Me)CH2CH=CHC(R)(R')NH- containing a six-membered ring framework. Using the precursors and the products of RCM, various CGC derivatives, i.e., [-Si(5-Me4C5)(Me)CH2CH=CHC(R)(H)N-]TiMe2 (13, R = H; 15, R = Me), [-Si(n5-Me4C5)(Me)CH2CH2CH2CH2N]TiMe2 (14), [(n5-Me4C5)Si(Me)(CH2CH=CH2)NCH2CH=CH2]TiMe2 (16), [(n5-Me4C5)Si(Me)(CH=CH2)NCH2CH=CH2]TiMe2 (17), and [(n5-Me4C5)Si(Me)(CH2CH3)NCH2CH2CH3]TiMe2 (18), were prepared. The catalytic activity of the newly prepared complexes was lower than that of CGC when activated with [Ph3C][B(C6F5)4]/iBu3Al. However, the catalytic activity of these species was improved by using tetrabutylaluminoxane ([iBu2Al]2O) instead of iBu3Al and the activity of 14/[Ph3C][B(C6F5)4]/[iBu2Al]2O was comparable to that of CGC/[Ph3C][B(C6F5)4]/iBu3Al (94 and 99 x 10^6 g/molTi·h, respectively). Advantageously, the newly prepared complexes produced higher molecular weight poly(ethylene-co-1-octene)s than CGC.
more목차
1. Introduction
2. Results and Discussion
2.1 Synthesis and Characterization
2.2 Polymerization study
3. Conclusion
4. Experimental Section
4.1 General remarks.
4.2 Synthesis of Compound 3-18
4.3 Ethylene/1-Octene copolymerization
5. Acknowledgements
6. Notes and References
7. Supporting Information
