東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Polymer Infiltration under Extreme C...

Ring, David J.

Linked to FindBook

Google Book

Amazon

博客來

Polymer Infiltration under Extreme Confinement.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Polymer Infiltration under Extreme Confinement./
Author:	Ring, David J.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2019,
Description:	98 p.
Notes:	Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
Contained By:	Dissertations Abstracts International81-05B.
Subject:	Chemical engineering. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22587476
ISBN:	9781088367919

Polymer Infiltration under Extreme Confinement.
Ring, David J.

Polymer Infiltration under Extreme Confinement. - Ann Arbor : ProQuest Dissertations & Theses, 2019 - 98 p.

Source: Dissertations Abstracts International, Volume: 81-05, Section: B.

Thesis (Ph.D.)--University of Pennsylvania, 2019.

This item must not be sold to any third party vendors.

Polymer nanocomposites with high nanoparticle loadings are ubiquitous in nature but difficult to replicate synthetically. A simple technique to create such polymer nanocomposites is to form a bi-layer of a nanoparticle thin film atop a polymer thin film and anneal above the polymer glass transition temperature to induce wicking. This Capillary Rise Infiltration (CaRI) of polymers into nanoparticle thin films is a promising method to create interesting biomimetic composites with enhanced material properties, but also raises important theoretical questions about confinement, capillarity, and polymer dynamics. Therefore, I use molecular dynamics simulations (MD) and continuum theory to understand the impact of confinement on infiltrating polymers. In Chapter 2, I observe that polymers will form porous nanocomposites when there is not enough polymer to fill the voids in the nanoparticle packings. These undersaturated CaRI systems (UCaRI) can be used to form graded or uniform porous composites if the bi-layer is annealed for short or long times, respectively. Due to polymer bridges formed during annealing, these porous nanocomposites have markedly enhanced mechanical properties even when the fraction of polymer is very low. Chapter 3 investigates the effect of confinement on critical contact angle above which infiltration halts. It is determined that the confinement of polymers in the melt does not significantly affect the critical contact angle, which remains independent of the chain length for sufficiently long chains, but depends strongly on the chain stiffness. Finally, Chapter 4 investigates the effect of varying cross-section on the free energy landscape of infiltrating polymers. I discover that barriers can be introduced into the infiltration free energy as a result of the large change in free surface area between constrictions and expansions along the length of the capillary. This leads to polymer infiltration that occurs stepwise from minimum to minimum, like an activated process. Thus, free energy due to wetting and confinement in nanopores has a significant impact on the infiltration behavior of polymers and the formation polymer nanocomposites.

ISBN: 9781088367919Subjects--Topical Terms:

560457
Chemical engineering.
Subjects--Index Terms:

Capillary

Polymer Infiltration under Extreme Confinement.
LDR:03434nmm a2200433 4500 001 2272696
005 20201105110159.5
008 220629s2019 ||||||||||||||||| ||eng d
020 $a 9781088367919
035 $a (MiAaPQ)AAI22587476
035 $a AAI22587476
040 $a MiAaPQ $c MiAaPQ
100 1 $a Ring, David J. $3 3550124
245 1 0 $a Polymer Infiltration under Extreme Confinement.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2019
300 $a 98 p.
500 $a Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
500 $a Advisor: Lee, Daeyeon;Riggleman, Robert A.
502 $a Thesis (Ph.D.)--University of Pennsylvania, 2019.
506 $a This item must not be sold to any third party vendors.
520 $a Polymer nanocomposites with high nanoparticle loadings are ubiquitous in nature but difficult to replicate synthetically. A simple technique to create such polymer nanocomposites is to form a bi-layer of a nanoparticle thin film atop a polymer thin film and anneal above the polymer glass transition temperature to induce wicking. This Capillary Rise Infiltration (CaRI) of polymers into nanoparticle thin films is a promising method to create interesting biomimetic composites with enhanced material properties, but also raises important theoretical questions about confinement, capillarity, and polymer dynamics. Therefore, I use molecular dynamics simulations (MD) and continuum theory to understand the impact of confinement on infiltrating polymers. In Chapter 2, I observe that polymers will form porous nanocomposites when there is not enough polymer to fill the voids in the nanoparticle packings. These undersaturated CaRI systems (UCaRI) can be used to form graded or uniform porous composites if the bi-layer is annealed for short or long times, respectively. Due to polymer bridges formed during annealing, these porous nanocomposites have markedly enhanced mechanical properties even when the fraction of polymer is very low. Chapter 3 investigates the effect of confinement on critical contact angle above which infiltration halts. It is determined that the confinement of polymers in the melt does not significantly affect the critical contact angle, which remains independent of the chain length for sufficiently long chains, but depends strongly on the chain stiffness. Finally, Chapter 4 investigates the effect of varying cross-section on the free energy landscape of infiltrating polymers. I discover that barriers can be introduced into the infiltration free energy as a result of the large change in free surface area between constrictions and expansions along the length of the capillary. This leads to polymer infiltration that occurs stepwise from minimum to minimum, like an activated process. Thus, free energy due to wetting and confinement in nanopores has a significant impact on the infiltration behavior of polymers and the formation polymer nanocomposites.
590 $a School code: 0175.
650 4 $a Chemical engineering. $3 560457
650 4 $a Computational chemistry. $3 3350019
650 4 $a Condensed matter physics. $3 3173567
650 4 $a Polymer chemistry. $3 3173488
650 4 $a Materials science. $3 543314
650 4 $a Physical chemistry. $3 1981412
650 4 $a Nanotechnology. $3 526235
653 $a Capillary
653 $a Confinement
653 $a Infiltration
653 $a Molecular dynamics
653 $a Nanoparticles
653 $a Polymer
690 $a 0542
690 $a 0219
690 $a 0611
690 $a 0495
690 $a 0494
690 $a 0794
690 $a 0652
710 2 $a University of Pennsylvania. $b Chemical and Biomolecular Engineering. $3 2101616
773 0 $t Dissertations Abstracts International $g 81-05B.
790 $a 0175
791 $a Ph.D.
792 $a 2019
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22587476