Ralph Colby

Affiliate Researcher
Titles and Affiliations
Professor, Materials Science and Engineering

Research Summary

Research interests include proteins, polyelectrolytes, ionomers, liquid crystalline polymers, block copolymers, miscible polymer blends, branched polymers, networks, glass-forming liquids, and surfactants and colloidal suspensions. Ion-containing polymers are a poorly understood class of materials that are potentially very important for actuators, sensors, separators between the electrodes of advanced batteries and fuel cell membranes.

In the News

Research Keywords

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Recent Publications

Ionic interactions control the modulus and mechanical properties of molecular ionic composite electrolytes

Bostwick, J. E., Zanelotti, C. J., Yu, D., Pietra, N. F., Williams, T., Madsen, L. A. & Colby, R. H., Jan 21 2022, In: Journal of Materials Chemistry C. 10, 3, p. 947-957 11 p.

Research output: Contribution to journalArticlepeer-review

Reflections and appreciations from the Journal 's Departing Editor

Colby, R. H., Jan 1 2022, In: Journal of Rheology. 66, 1, p. 235 1 p.

Research output: Contribution to journalEditorialpeer-review

Predicting the Plateau Modulus from Molecular Parameters of Conjugated Polymers

Fenton, A. M., Xie, R., Aplan, M. P., Lee, Y., Gill, M. G., Fair, R., Kempe, F., Sommer, M., Snyder, C. R., Gomez, E. D. & Colby, R. H., Feb 23 2022, In: ACS Central Science. 8, 2, p. 268-274 7 p.

Research output: Contribution to journalArticlepeer-review

Determining the Molecular Weight of Polyelectrolytes Using the Rouse Scaling Theory for Salt-Free Semidilute Unentangled Solutions

Han, A., Uppala, V. V. S., Parisi, D., George, C., Dixon, B. J., Ayala, C. D., Li, X., Madsen, L. A. & Colby, R. H., Aug 23 2022, In: Macromolecules. 55, 16, p. 7148-7160 13 p.

Research output: Contribution to journalArticlepeer-review

Anion chemical composition of poly(ethylene oxide)-based sulfonylimide and sulfonate lithium ionomers controls ion aggregation and conduction

Mei, W., Yu, D., George, C., Madsen, L. A., Hickey, R. J. & Colby, R. H., Sep 2 2022, In: Journal of Materials Chemistry C. 10, 39, p. 14569-14579 11 p.

Research output: Contribution to journalArticlepeer-review

Molecular Weight Characterization of Conjugated Polymers through Gel Permeation Chromatography and Static Light Scattering

Fair, R. A., Xie, R., Lee, Y., Colby, R. H. & Gomez, E. D., Sep 10 2021, In: ACS Applied Polymer Materials. 3, 9, p. 4572-4578 7 p.

Research output: Contribution to journalArticlepeer-review

Rheology of Entangled Polyelectrolyte Solutions

Han, A. & Colby, R. H., Feb 9 2021, In: Macromolecules. 54, 3, p. 1375-1387 13 p.

Research output: Contribution to journalArticlepeer-review

Effect of chemical substituents attached to the zwitterion cation on dielectric constant

Mei, W., Han, A., Hickey, R. J. & Colby, R. H., Dec 28 2021, In: Journal of Chemical Physics. 155, 24, 244505.

Research output: Contribution to journalArticlepeer-review

Zwitterions Raise the Dielectric Constant of Soft Materials

Mei, W., Rothenberger, A. J., Bostwick, J. E., Rinehart, J. M., Hickey, R. J. & Colby, R. H., Nov 24 2021, In: Physical review letters. 127, 22, 228001.

Research output: Contribution to journalArticlepeer-review

Rheology, Sticky Chain, and Sticker Dynamics of Supramolecular Elastomers Based on Cluster-Forming Telechelic Linear and Star Polymers

Mordvinkin, A., Döhler, D., Binder, W. H., Colby, R. H. & Saalwächter, K., Jun 8 2021, In: Macromolecules. 54, 11, p. 5065-5076 12 p.

Research output: Contribution to journalArticlepeer-review

Rheological response of entangled isotactic polypropylene melts in strong shear flows: Edge fracture, flow curves, and normal stresses

Parisi, D., Han, A., Seo, J. & Colby, R. H., Jul 1 2021, In: Journal of Rheology. 65, 4, p. 605-616 12 p.

Research output: Contribution to journalArticlepeer-review

Shear-induced nematic phase in entangled rod-like PEEK melts

Parisi, D., Seo, J., Schaake, R. P., Rhoades, A. M. & Colby, R. H., Jan 2021, In: Progress in Polymer Science. 112, 101323.

Research output: Contribution to journalReview articlepeer-review

Dual Nakamura model for primary and secondary crystallization applied to nonisothermal crystallization of poly(ether ether ketone)

Seo, J., Zhang, X., Schaake, R. P., Rhoades, A. M. & Colby, R. H., Oct 2021, In: Polymer Engineering and Science. 61, 10, p. 2416-2426 11 p.

Research output: Contribution to journalArticlepeer-review

Room Temperature to 150 °C Lithium Metal Batteries Enabled by a Rigid Molecular Ionic Composite Electrolyte

Yu, D., Pan, X., Bostwick, J. E., Zanelotti, C. J., Mu, L., Colby, R. H., Lin, F. & Madsen, L. A., Mar 25 2021, In: Advanced Energy Materials. 11, 12, 2003559.

Research output: Contribution to journalArticlepeer-review

Ion Transport and Mechanical Properties of Non-Crystallizable Molecular Ionic Composite Electrolytes

Bostwick, J. E., Zanelotti, C. J., Iacob, C., Korovich, A. G., Madsen, L. A. & Colby, R. H., Feb 25 2020, In: Macromolecules. 53, 4, p. 1405-1414 10 p.

Research output: Contribution to journalArticlepeer-review