Moscato Beth, Landis Clark
Dept. of Chemistry, UW-Madison, 1101 University, Madison, WI, USA.
Chem Commun (Camb). 2008 Nov 30(44):5785-7. doi: 10.1039/b812133h. Epub 2008 Oct 1.
Polyethylene molecular weight distributions observed by ESI-MS following the quench of a Cp(2)ZrCl(2)/MAO-catalyzed ethylene polymerization with N,N'-dicyclohexylcarbodiimide do not agree with GPC or NMR analysis of methanol-d(1) quenched samples; factors contributing to the discrepant results include high sample polydispersities, polymer insolubility, and the incomplete quench of metal-polymer species. Kinetic analyses of molecular weight distributions obtained by ESI-MS are not representative of the predominate monomer-consuming pathways.
在用N，N'-二环己基碳二亚胺猝灭Cp(2)ZrCl(2)/MAO催化的乙烯聚合反应后，通过电喷雾电离质谱（ESI-MS）观察到的聚乙烯分子量分布与用氘代甲醇（methanol-d(1)）猝灭的样品的凝胶渗透色谱（GPC）或核磁共振（NMR）分析结果不一致；导致结果存在差异的因素包括高样品多分散性、聚合物不溶性以及金属-聚合物物种的不完全猝灭。通过ESI-MS获得的分子量分布的动力学分析不能代表主要的单体消耗途径。
