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Updated: Mar 15, 2026
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
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Rheological Behavior and Molecular Interactions in Concentrated Polycarbosilane Solutions in Linear and Cyclic
Mikhail S Kuzin1, Maria F Lobanova1, Pavel S Gerasimenko1
1A.V. Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences, 119991 Moscow, Russia.
Polymers
|March 14, 2026
Summary
Linear heptadecane enables the creation of stable, deformable polycarbosilane (PCS) solutions for advanced silicon carbide (SiC) fiber spinning. This discovery offers a new pathway for elasticity-controlled processing in SiC precursor fiber technology.
Area of Science:
- Materials Science
- Polymer Chemistry
- Chemical Engineering
Background:
- Concentrated polycarbosilane (PCS) solutions are crucial for developing continuous silicon carbide (SiC) precursor fibers.
- Solvent-polymer interactions significantly influence the rheology, stability, and spinnability of these solutions.
Purpose of the Study:
- To investigate the impact of solvent molecular architecture on PCS solutions in the semi-dilute entangled and concentrated regimes.
- To understand the structure-rheology-processability relationship in PCS systems for fiber spinning applications.
Main Methods:
- Systematic investigation of PCS solutions in linear n-heptadecane and bicyclic decalin.
- Combined use of steady and oscillatory rheometry and Fourier transform infrared (FTIR) spectroscopy.
Main Results:
- Concentrated PCS solutions exhibit significant solvent-dependent differences in elasticity and flow behavior, despite similar dilute-solution parameters.
- Linear heptadecane promotes thermostable, homogeneous PCS solutions with enhanced deformability, unlike decalin.
- Identified solvent molecular geometry as the key factor governing the structure-rheology-processability relationship.
Conclusions:
- Linear heptadecane is a promising solvent for PCS, enabling a new solution-based fiber-spinning route.
- Solvent molecular geometry, not just solubility parameters, dictates the processability of concentrated PCS systems.
- Provides a novel framework for selecting solvents in SiC precursor fiber technology.
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