Doctoral Dissertations

Peng Geng

Keywords and Phrases

Colloidal Unimolecular Polymer (CUP); Evaporation Rate; Heat of Fusion; Melting Point Depression; Specific Heat; Surface Water

Abstract

“Colloidal Unimolecular Polymer (CUP) is spheroidal nanoscale polymer particle (3-9 nm) with charged hydrophilic gruops on the surface and a hydrophobic core. The formation of CUPs involves a simple free radical polymerization and a water reduction process. CUPs are thermodynamically stable in water, molecular weight, particle size and charge density can be designed and controlled. CUPs have a layer of surface associated water, due to the small particle size, the surface water/CUP volume ratio is ultra-high. Therefore, CUP is a very promising candidate to investigate the thermodynamic of surface water characteristics. In addition, CUP solution is free of surfactant and has zero volatile content, which exhibit great potential in coatings applications. DSC evaluation was performed to determine the characteristics of surface water. Surface water thickness varies from 0.427 to 0.766 nm, and it is charge density dependent. The surface water has a larger density than free water and increased with the increase in surface charge density. The specific heat of surface water was found to be 3.04~3.07 J/g·K at 253.15 K and 3.07~3.09 J/g·K at 293.15 K, which was larger than ice but smaller than free water. The average area occupied by carboxylate and ester groups on the CUP surface were determined to be 0.287 nm2 and 0.374 nm2. The evaporation rate of CUP solutions was investigated by TGA, results showed that CUP was capable to increase the evaporation rate of free water due to the deformation of air-water interface, caused by electrostatic repulsion. Surface water presented a much slower evaporation rate compared with free water, and did not evaporate until there is no free water. Thus, CUP was able to be used as an additive to give freeze thaw stability, wet edge retention and open time for coatings”--Abstract, page iv

Advisor(s)

Van-De-Mark, Michael R.

Committee Member(s)

Sotiriou-Leventis, Lia
Winiarz, Jeffrey G.
Reddy, Prakash
Bai, Baojun

Department(s)

Chemistry

Degree Name

Ph. D. in Chemistry

Comments

The authors would like to thank the Department of Chemistry for the use of the DSC and the Missouri S&T Coating Institute for financial support.

Publisher

Missouri University of Science and Technology

Publication Date

Summer 2020

Journal article titles appearing in thesis/dissertation

  • Thermodynamic characterization of free and surface water of colloidal unimolecular polymer (CUP) particles utilizing DSC
  • Investigation of the evaporation rate of water from colloidal unimolecular polymer (CUP) systems by isothermal TGA
  • DSC and TGA characterization of free and surface water of colloidal unimolecular polymer (CUP) particles for coatings applications

Pagination

xvii, 140 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2020 Peng Geng, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 11743

Electronic OCLC #

1198498989

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Included in

Chemistry Commons

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