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Solvent-free, supersoft and superelastic bottlebrush melts and networks


Polymer gels are the only viable class of synthetic materials with a Young’s modulus below 100 kPa conforming to biological applications1,2,3, yet those gel properties require a solvent fraction4,5,6,7. The presence of a solvent can lead to phase separation, evaporation and leakage on deformation, diminishing gel elasticity and eliciting inflammatory responses in any surrounding tissues. Here, we report solvent-free, supersoft and superelastic polymer melts and networks prepared from bottlebrush macromolecules. The brush-like architecture expands the diameter of the polymer chains, diluting their entanglements without markedly increasing stiffness. This adjustable interplay between chain diameter and stiffness makes it possible to tailor the network’s elastic modulus and extensibility without the complications associated with a swollen gel. The bottlebrush melts and elastomers exhibit an unprecedented combination of low modulus (100 Pa), high strain at break (1,000%), and extraordinary elasticity, properties that are on par with those of designer gels8,9.

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Figure 1: Transitioning from polymer molecules to mesoscopic filaments.
Figure 2: Theoretically predicted and experimentally visualized bottlebrush conformations.
Figure 3: Analysis of dynamic mechanical master curves and universal behaviour.
Figure 4: Supersoft and superextendable elastomers.


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We gratefully acknowledge financial support from the National Science Foundation (DMR 1409710, DMR 1122483, DMR 1407645 and DMR 1436201). J.P. acknowledges financial support provided by a Polish Ministry of Science and Higher Education Grant (IP2012 005072). We also thank E. Zhulina for illuminating discussion, R. Colby of Penn State University for training in rheological techniques, and E. T. Samulski for reviewing the paper.

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W.F.M.D. performed LB-AFM experiments and analysis, rheology experiments and analysis, and wrote the manuscript. J.B. and K.M. synthesized BA bottlebrush polymers and performed GPC and chain cleavage analysis. M.V.-V. synthesized pDMS elastomers, J.P. performed computer simulations of bottlebrush melts, and M.R. and A.V.D. provided theoretical predictions. S.S.S. was the primary investigator.

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Correspondence to Sergei S. Sheiko.

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The authors declare no competing financial interests.

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Daniel, W., Burdyńska, J., Vatankhah-Varnoosfaderani, M. et al. Solvent-free, supersoft and superelastic bottlebrush melts and networks. Nature Mater 15, 183–189 (2016).

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