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Programming of shape memory natural rubber for near-discrete shape transitions
Dominik Quitmann1, Frauke M Reinders, Benjamin Heuwers
1Chair of Biomaterials & Polymer Science, Department of Biochemical & Chemical Engineering, TU Dortmund , D-44221 Dortmund, Germany.
ACS Applied Materials & Interfaces
|December 24, 2014
Summary
Cold-programmed shape memory natural rubber (SMNR) exhibits a narrow 1 K transition range, recovering over 80% of its original shape. Trigger points are tunable via aging or solvent vapor treatment, enabling programming of higher cross-linked natural rubber.
Area of Science:
- Materials Science
- Polymer Science
Background:
- Traditional shape memory polymers require high-temperature programming and exhibit broad shape transition ranges.
- Shape memory natural rubber (SMNR) offers a promising alternative with cold-programming capabilities.
Purpose of the Study:
- To investigate methods for enhancing the trigger point of cold-programmed SMNR while maintaining its narrow transition range.
- To explore the effects of aging and solvent vapor treatment on SMNR programming.
Main Methods:
- Cold-programming of shape memory natural rubber (SMNR).
- Inducing shape recovery within a narrow temperature range (1 K).
- Investigating the influence of aging on the trigger point.
- Accelerating trigger point increase using nonaffine and affine solvent vapors.
Main Results:
- SMNR recovers over 80% of its original shape within a 1 K temperature range.
- Aging stretched SMNR increases the trigger point without broadening the transition.
- Treatment with nonaffine solvent vapors accelerates the trigger point increase.
- Affine solvent vapors at low concentrations yield higher trigger points than aging.
Conclusions:
- Cold-programming of SMNR is feasible with a narrow transition range.
- Aging and solvent vapor treatments effectively increase the trigger point of SMNR.
- This methodology allows for the cold-programming of even higher cross-linked natural rubber.
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