Product Name: 9,9-Bis(methoxymethyl)fluorene
Synonym: 9,9-bis(methoxymethyl)-9H-fluorene
Cas no: 182121-12-6
Heterogeneous Ziegler-Natta (Z-N) catalysts are synthesized using magnesium dichloride (MgCl₂) as
a support. During the loading of titanium tetrachloride (TiCl₄), an internal donor is incorporated to
form the main catalyst.
In propylene polymerization, an alkylaluminum co-catalyst and an external donor are added.
Both internal and external donors play crucial roles in enhancing catalyst activity and controlling
the isotacticity of polypropylene.Compounds featuring a 1,3-dimethoxypropane structural moiety
represent a novel class of donors. These can achieve very high activity and high isotacticity in
polypropylene even in the absence of an external donor. This significantly reduces the complexity of the
polymerization system, offering substantial practical value.
Different structural types of diethers, when used as internal donors in Z-N catalysts, exhibit distinct
application characteristics.9,9-Bis(methoxymethyl)fluorene is a representative example of a diether
internal donor:
European Patent EP0728770 (Montell North America, 1996) states that a catalyst using
9,9-bis(methoxymethyl)fluorene as the internal donor achieved an activity of 95,000 g polypropylene
per gram of catalyst and an isotacticity of 97.7%. The specific application scenarios and performance of
internal donors also depend significantly on the development efforts of the user.
