Internal Donor for Ziegler-Natta (Z-N) Catalysts
Product Name: Isopropyl-2-isopentyl-1,3-propanediol DimethylEther
Synonym: 2-isopropyl-2-(1-methylbutyl)-1,3-dimethoxypropane
Cas no: 129228-11-1
Heterogeneous Ziegler-Natta (Z-N) catalysts are synthesized with magnesium dichloride as the
support.During the loading of titanium tetrachloride,an internal donor is incorporated to form
the main catalyst.Alkylaluminum cocatalysts and external donors are added during propylene
polymerization.
Both internal and external donors play crucial roles in enhancing catalyst activity and controlling
the isotacticity of polypropylene,among other properties.Compounds containing the 1,3-propanediol
dimethyl ether structural motif represent a novel class of donors.
These can achieve high activity and high isotacticity in polypropylene even without an external donor.
This significantly reduces thecomplexity of the polymerization system and holds substantial practical
value.
Different structural types of diethers, when used as internal donors in Z-N catalysts, exhibit distinct
application characteristics.2-Isopropyl-2-isopentyl-1,3-propanediol dimethyl ether, also known as
2-isopropyl-2-isopentyl-1,3-dimethoxypropane, is a typical representatve of the diether internal
donor class:
European Patent EP0362705 (Montedison, 1989) indicates that using 2-isopropyl-2-isopentyl-
1,3-propanediol dimethyl ether as the internal donor achieves a catalytic activity of 3950 g
polypropylene per gram catalyst (3950 g PP/g cat) and an isotacticity of 98.5%.The specific
application scenarios and performance of the internal donor also depend significantly on the user’s
development efforts.
