Related Experiment Video
Updated: Sep 3, 2025
07:02
The Preparation and Properties of Thermo-reversibly Cross-linked Rubber Via Diels-Alder Chemistry
Published on: August 25, 2016
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Thermally Activable Bistetrazoles for Elastomers Crosslinking.
Mauro Monti1, Luca Giannini2, Luciano Tadiello2
1Department of Materials Science, University of Milano-Bicocca, Via Cozzi 55, 20125 Milano, Italy.
Polymers
|July 27, 2022
Summary
New bis-tetrazole compounds offer improved control over rubber crosslinking. These additives enhance elastomer properties and simplify the compounding process for better material performance.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Sulfur vulcanization is the primary method for rubber curing, but controlling crosslink density and homogeneity remains challenging.
- Existing methods rely on complex additive packages (accelerants, activators, etc.) to fine-tune elastomer properties like hardness and elasticity.
- Difficulty in precise control over crosslinking affects the final material properties and performance.
Purpose of the Study:
- To explore bis-tetrazoles as novel crosslinking agents for elastomers.
- To evaluate their effectiveness as standalone crosslinkers and in conjunction with sulfur-based systems.
- To assess the impact of bis-tetrazoles on the compounding process and final material properties.
Main Methods:
- Synthesis of a series of bis-tetrazole compounds.
- Thermal activation of selected bis-tetrazoles to generate reactive nitrilimines.
- Curing of styrene-butadiene rubber (SBR) using bis-tetrazoles, both independently and with sulfur-based crosslinkers.
- Evaluation of compounding efficiency, dispersion, homogeneity, and material properties (hysteresis, Payne effect).
Main Results:
- Bis-tetrazoles simplified and improved the efficiency of the rubber compounding process.
- The use of bis-tetrazoles allowed for prolonged mixing, leading to better dispersion and homogeneity.
- Compounds cured with bis-tetrazoles exhibited improved hysteretic properties and reduced Payne effect (non-linearity).
Conclusions:
- Bis-tetrazoles represent a viable strategy for modulating and precisely controlling elastomer reticulation.
- These compounds enhance the compounding process and improve key dynamic properties of styrene-butadiene rubber.
- The study demonstrates the potential of thermally activable bifunctional reagents in advanced rubber material development.
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