Soluble neodymium chloride 2-ethylhexanol complex as a highly active catalyst for controlled isoprene polymerization
Data(s) |
2007
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Resumo |
Soluble NdCl3 center dot 3EHOH (2-ethyl hexanol) in hexane combined with AlEt3 is highly active for isoprene polymerization in hexane. The NdCl3 center dot 3EHOH/AlEt3 has higher activity than the typical binary catalyst NdCl3 center dot 3(i)PrOH (isopropanol)/AlEt3 and ternary catalyst NdV3 (neodymium versatate)/AlEt2Cl/Al(i-Bu)(2)H. The molecular weight of polyisoprenes can be controlled by variation of [Nd], [Al]/[Nd] ratio and polymerization temperature and time. The NdCl3 center dot 3EHOH/AlEt3 catalyst polymerized isoprene to afford products featuring high cis-1,4 stereospecificity (ca. 96%), high molecular weight (ca. 10(5)) and relatively narr ow molecular weight distributions (M-w/M-n = 2.0-2.8) simultaneously. More importantly, some living polymerization characteristics were demonstrated: (a) absence of chain termination; (b) linear correlation between M-n and polymer yield; (c) increment of molecular weight in the 'seeding' polymerization. Though some deviation from the typical living polymerization such as molecular weight distribution is not narrow enough and the line of M-n and polymer yield does not extrapolate to zero, controlled polymerization with the current catalyst can still be concluded. |
Identificador | |
Idioma(s) |
英语 |
Fonte |
Ren CY;Li GL;Dong WM;Jiang LS;Zhang XQ;Wang FS.Soluble neodymium chloride 2-ethylhexanol complex as a highly active catalyst for controlled isoprene polymerization,POLYMER ,2007 ,48(9):2470-2474 |
Palavras-Chave | #METHYLALUMINOXANE CATALYST #BUTADIENE #1 #1 #SYSTEMS #3-BUTADIENE #3-DIENES |
Tipo |
期刊论文 |