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Updated: Aug 5, 2026
09:08
A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Tunable and Predictable Bimodal Metathesis Polymers Enabled by Fusion Catalysis-Controlled Polymerization of
Chao Wang1, Tian-Tian Wang1, Zheng-Hong Luo1
1State Key Laboratory of Polyolefins and Catalysis, Shanghai Key Laboratory of Catalysis Technology for Polyolefins, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
JACS Au
|July 30, 2026
Summary
A novel dual-catalysis method enables precise control over polymer molecular weight distribution (MWD) using one-pot ring-opening metathesis polymerization (ROMP). This strategy allows for tunable bimodal distributions, advancing polymer property control.
Area of Science:
- Polymer Chemistry
- Materials Science
- Catalysis
Background:
- Molecular weight distribution (MWD) is critical for polymer properties.
- Controlling MWD shape in polymerization is kinetically challenging.
- Existing methods lack fine control over MWD profiles.
Purpose of the Study:
- To develop a strategy for tunable bimodal MWD via one-pot polymerization.
- To achieve precise control over MWD parameters like peak spacing and height.
- To understand the mechanism of bimodal distribution formation.
Main Methods:
- Employed a dual-catalysis system with two metathesis catalysts for ring-opening metathesis polymerization (ROMP) of norbornene.
- Varied catalyst composition ratio, polymerization time, and total catalyst loading to tune MWD.
- Utilized rheological measurements, kinetic experiments, and theoretical computations.
Main Results:
- Successfully constructed tunable bimodal MWD with controlled peak spacing (23.8-170.0 kg/mol) and relative peak height (0.2-1.0).
- Bimodal polymers exhibited reduced storage modulus (G') and complex viscosity (η*) compared to unimodal counterparts.
- A predictive equation was derived to correlate catalyst composition with MWD, based on a fusion-catalysis mechanism.
Conclusions:
- The dual-catalysis strategy offers unprecedented control over MWD shape in one-pot ROMP.
- The fusion-catalysis mechanism explains dynamic chain shuttling between catalysts.
- This work advances MWD engineering for broader applications in polymer science.
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