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Updated: Dec 31, 2025

Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
Determination of the Intermolecular Entanglement Coupling Spacings in Polyisoprene by Viscosity Measurements
1National Academy of Sciences-National Research Council Postdoctoral Resident Research Associate.
The entanglement molecular weight for polyisoprene was determined using solution viscosity measurements at various concentrations. Results confirmed theoretical predictions and showed no temperature dependence between 25-75°C.
Area of Science:
- Polymer Science
- Rheology
- Physical Chemistry
Background:
- Understanding polymer chain entanglement is crucial for predicting material properties.
- Solution viscosity is a key parameter for characterizing polymer behavior.
Purpose of the Study:
- To estimate the entanglement molecular weight (Me) of polyisoprene.
- To investigate the influence of polymer concentration on Me.
- To determine the effect of temperature on Me.
Main Methods:
- Solution viscosity measurements were performed on polyisoprene samples.
- Experiments were conducted at polymer concentrations of 1.82, 3.64, and 14.56 g/100 cm³.
- Viscosity data were analyzed to determine the dependence on molecular weight and concentration.
Main Results:
- Theoretical relationships between viscosity and molecular weight were confirmed.
- The predicted dependence of entanglement molecular weight on polymer concentration was substantiated.
- No variation in entanglement molecular weight was observed between 25 °C and 75 °C.
Conclusions:
- The entanglement molecular weight of polyisoprene can be reliably estimated from solution viscosity.
- Polymer concentration significantly influences entanglement molecular weight, as predicted by theory.
- Temperature does not affect the entanglement molecular weight of polyisoprene within the studied range.
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