東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Controlling Assembly of Polymer-Graf...

Zhang, Aria Chen,

FindBook

Google Book

Amazon

博客來

Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films /

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films // Aria Chen Zhang.
作者:	Zhang, Aria Chen,
面頁冊數:	1 electronic resource (227 pages)
附註:	Source: Dissertations Abstracts International, Volume: 86-12, Section: B.
Contained By:	Dissertations Abstracts International86-12B.
標題:	Polymer chemistry. -
電子資源:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31843159
ISBN:	9798280760707

Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films /
Zhang, Aria Chen,

Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films /Aria Chen Zhang. - 1 electronic resource (227 pages)

Source: Dissertations Abstracts International, Volume: 86-12, Section: B.

Polymer nanocomposite (PNC) films are of interest for many applications including electronics, energy storage, and advanced coatings. In phase-separating PNCs, the interplay between thermodynamic and kinetic factors governs the assembly of polymer-grafted nanoparticles (NPs), which directly influences material properties. Understanding how processing parameters affect the structure-property relationship of PNCs is important for designing advanced materials. This thesis provides insight by investigating a model PNC system of poly(methyl methacrylate)-grafted nanoparticles (PMMA-NPs) embedded in a poly(styrene-ran-acrylonitrile) (SAN) matrix.Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was developed to quantify the distribution of NPs within PMMA-NP/SAN films, enabling precise 3D reconstruction of PNC structures. Experimental parameters such as primary ion beam angle and charge compensation were optimized to enhance secondary ion signals and depth resolution. Upon annealing in the two-phase region, PMMA-NP/SAN films exhibited phase separation and surface segregation, leading to morphological evolutions characterized by atomic force microscopy (AFM), ToF-SIMS, water contact angle measurements, and transmission electron microscopy. By systematically exploring the effects of film thickness on PNC structures, we found that film thickness-induced confinement reduces lateral phase separation and enhances NP dispersion at the surface. A dimensional crossover from three to two dimensions was observed around 240 nm, below which surface-directed spinodal decomposition is suppressed. As a result of phase separation and surface segregation, six distinct bulk morphologies were identified, allowing for the construction of a morphology map correlating film thickness and annealing time. Among these morphologies, percolated structures were found to improve mechanical properties such as hardness and reduced modulus, as measured using AFM nanoindentation. Notably, interconnected networks show the highest hardness and modulus at both low and high force loadings. Additionally, Marangoni-induced hexagonal honeycomb patterns were observed in spin-coated as-cast PMMA-NP/SAN films. By changing to a less volatile solvent, these defects were eliminated, demonstrating the importance of solvent selection in achieving uniform and high-quality thin films.These findings demonstrate the potential for precise control of surface-enriched and phase-separated microstructures in PNC films through tailoring processing conditions. This thesis advances the understanding of processing-structure-property relationships in PNCs, providing a foundation for designing highly functional materials with broad industrial applications.

English

ISBN: 9798280760707Subjects--Topical Terms:

3173488
Polymer chemistry.
Subjects--Index Terms:

Mechanical properties

Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films /
LDR:04271nmm a22004453i 4500 001 2434813
005 20251001062530.5
006 m o d
007 cr|nu||||||||
008 261011s2025 miu||||||m |||||||eng d
020 $a 9798280760707
035 $a (MiAaPQD)AAI31843159
035 $a AAI31843159
040 $a MiAaPQD $b eng $c MiAaPQD $e rda
100 1 $a Zhang, Aria Chen, $e author. $3 3824927
245 1 0 $a Controlling Assembly of Polymer-Grafted Nanoparticles to Enhance Mechanical Properties in Polymer Nanocomposite Films / $c Aria Chen Zhang.
264 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2025
300 $a 1 electronic resource (227 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 86-12, Section: B.
500 $a Advisors: Composto, Russell J. Committee members: Winey, Karen I.; Riggleman, Robert A.; Stach, Eric A.
502 $b Ph.D. $c University of Pennsylvania $d 2025.
520 $a Polymer nanocomposite (PNC) films are of interest for many applications including electronics, energy storage, and advanced coatings. In phase-separating PNCs, the interplay between thermodynamic and kinetic factors governs the assembly of polymer-grafted nanoparticles (NPs), which directly influences material properties. Understanding how processing parameters affect the structure-property relationship of PNCs is important for designing advanced materials. This thesis provides insight by investigating a model PNC system of poly(methyl methacrylate)-grafted nanoparticles (PMMA-NPs) embedded in a poly(styrene-ran-acrylonitrile) (SAN) matrix.Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was developed to quantify the distribution of NPs within PMMA-NP/SAN films, enabling precise 3D reconstruction of PNC structures. Experimental parameters such as primary ion beam angle and charge compensation were optimized to enhance secondary ion signals and depth resolution. Upon annealing in the two-phase region, PMMA-NP/SAN films exhibited phase separation and surface segregation, leading to morphological evolutions characterized by atomic force microscopy (AFM), ToF-SIMS, water contact angle measurements, and transmission electron microscopy. By systematically exploring the effects of film thickness on PNC structures, we found that film thickness-induced confinement reduces lateral phase separation and enhances NP dispersion at the surface. A dimensional crossover from three to two dimensions was observed around 240 nm, below which surface-directed spinodal decomposition is suppressed. As a result of phase separation and surface segregation, six distinct bulk morphologies were identified, allowing for the construction of a morphology map correlating film thickness and annealing time. Among these morphologies, percolated structures were found to improve mechanical properties such as hardness and reduced modulus, as measured using AFM nanoindentation. Notably, interconnected networks show the highest hardness and modulus at both low and high force loadings. Additionally, Marangoni-induced hexagonal honeycomb patterns were observed in spin-coated as-cast PMMA-NP/SAN films. By changing to a less volatile solvent, these defects were eliminated, demonstrating the importance of solvent selection in achieving uniform and high-quality thin films.These findings demonstrate the potential for precise control of surface-enriched and phase-separated microstructures in PNC films through tailoring processing conditions. This thesis advances the understanding of processing-structure-property relationships in PNCs, providing a foundation for designing highly functional materials with broad industrial applications.
546 $a English
590 $a School code: 0175
650 4 $a Polymer chemistry. $3 3173488
650 4 $a Nanotechnology. $3 526235
650 4 $a Materials science. $3 543314
650 4 $a Mechanical engineering. $3 649730
653 $a Mechanical properties
653 $a Morphology
653 $a Polymer nanocomposites
653 $a Thin films
653 $a Surface segregation
690 $a 0794
690 $a 0495
690 $a 0652
690 $a 0548
710 2 $a University of Pennsylvania. $b Materials Science and Engineering. $e degree granting institution. $3 3824370
720 1 $a Composto, Russell J. $e degree supervisor.
773 0 $t Dissertations Abstracts International $g 86-12B.
790 $a 0175
791 $a Ph.D.
792 $a 2025
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31843159