Glass transition behavior of hyper-branched polystyrenes

Kei ichi Akabori, Hironori Atarashi, Masaaki Ozawa, Tetsuo Kondo, Toshihiko Nagamura, Keiji Tanaka

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Hyper-branched polystyrenes (HBPS) were synthesized. The bulk glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) for two kinds of HBPS with an equivalent Mw, which were fractionated from different lots, were different, being respectively higher and lower than that of the corresponding linear polystyrene (PS). Infrared spectroscopy revealed that the Tg of HBPS increased with an increasing extent of intramolecular cross-linking, or cyclization, in the molecule. The segmental dynamics of HBPS was examined by dynamic mechanical analysis. The relaxation temperature for the segmental motion in HBPS was consistent with the DSC results. The fragility index was always lower for HBPS than for the linear PS, regardless of its primary structure and chain end chemistry. This would indicate that the segmental motion for HBPS is less cooperative than that of the linear PS, probably due to a lack of intermolecular chain entanglements in HBPS.

Original languageEnglish
Pages (from-to)4868-4875
Number of pages8
Journalpolymer
Volume50
Issue number20
DOIs
Publication statusPublished - Sep 23 2009

Fingerprint

Polystyrenes
Glass transition
Differential scanning calorimetry
Cyclization
Dynamic mechanical analysis
Infrared spectroscopy

All Science Journal Classification (ASJC) codes

  • Organic Chemistry
  • Polymers and Plastics
  • Materials Chemistry

Cite this

Glass transition behavior of hyper-branched polystyrenes. / Akabori, Kei ichi; Atarashi, Hironori; Ozawa, Masaaki; Kondo, Tetsuo; Nagamura, Toshihiko; Tanaka, Keiji.

In: polymer, Vol. 50, No. 20, 23.09.2009, p. 4868-4875.

Research output: Contribution to journalArticle

Akabori, KI, Atarashi, H, Ozawa, M, Kondo, T, Nagamura, T & Tanaka, K 2009, 'Glass transition behavior of hyper-branched polystyrenes', polymer, vol. 50, no. 20, pp. 4868-4875. https://doi.org/10.1016/j.polymer.2009.08.029
Akabori, Kei ichi ; Atarashi, Hironori ; Ozawa, Masaaki ; Kondo, Tetsuo ; Nagamura, Toshihiko ; Tanaka, Keiji. / Glass transition behavior of hyper-branched polystyrenes. In: polymer. 2009 ; Vol. 50, No. 20. pp. 4868-4875.
@article{7ddb4fd57fc644869038ead00d0e3ce7,
title = "Glass transition behavior of hyper-branched polystyrenes",
abstract = "Hyper-branched polystyrenes (HBPS) were synthesized. The bulk glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) for two kinds of HBPS with an equivalent Mw, which were fractionated from different lots, were different, being respectively higher and lower than that of the corresponding linear polystyrene (PS). Infrared spectroscopy revealed that the Tg of HBPS increased with an increasing extent of intramolecular cross-linking, or cyclization, in the molecule. The segmental dynamics of HBPS was examined by dynamic mechanical analysis. The relaxation temperature for the segmental motion in HBPS was consistent with the DSC results. The fragility index was always lower for HBPS than for the linear PS, regardless of its primary structure and chain end chemistry. This would indicate that the segmental motion for HBPS is less cooperative than that of the linear PS, probably due to a lack of intermolecular chain entanglements in HBPS.",
author = "Akabori, {Kei ichi} and Hironori Atarashi and Masaaki Ozawa and Tetsuo Kondo and Toshihiko Nagamura and Keiji Tanaka",
year = "2009",
month = "9",
day = "23",
doi = "10.1016/j.polymer.2009.08.029",
language = "English",
volume = "50",
pages = "4868--4875",
journal = "Polymer",
issn = "0032-3861",
publisher = "Elsevier BV",
number = "20",

}

TY - JOUR

T1 - Glass transition behavior of hyper-branched polystyrenes

AU - Akabori, Kei ichi

AU - Atarashi, Hironori

AU - Ozawa, Masaaki

AU - Kondo, Tetsuo

AU - Nagamura, Toshihiko

AU - Tanaka, Keiji

PY - 2009/9/23

Y1 - 2009/9/23

N2 - Hyper-branched polystyrenes (HBPS) were synthesized. The bulk glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) for two kinds of HBPS with an equivalent Mw, which were fractionated from different lots, were different, being respectively higher and lower than that of the corresponding linear polystyrene (PS). Infrared spectroscopy revealed that the Tg of HBPS increased with an increasing extent of intramolecular cross-linking, or cyclization, in the molecule. The segmental dynamics of HBPS was examined by dynamic mechanical analysis. The relaxation temperature for the segmental motion in HBPS was consistent with the DSC results. The fragility index was always lower for HBPS than for the linear PS, regardless of its primary structure and chain end chemistry. This would indicate that the segmental motion for HBPS is less cooperative than that of the linear PS, probably due to a lack of intermolecular chain entanglements in HBPS.

AB - Hyper-branched polystyrenes (HBPS) were synthesized. The bulk glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) for two kinds of HBPS with an equivalent Mw, which were fractionated from different lots, were different, being respectively higher and lower than that of the corresponding linear polystyrene (PS). Infrared spectroscopy revealed that the Tg of HBPS increased with an increasing extent of intramolecular cross-linking, or cyclization, in the molecule. The segmental dynamics of HBPS was examined by dynamic mechanical analysis. The relaxation temperature for the segmental motion in HBPS was consistent with the DSC results. The fragility index was always lower for HBPS than for the linear PS, regardless of its primary structure and chain end chemistry. This would indicate that the segmental motion for HBPS is less cooperative than that of the linear PS, probably due to a lack of intermolecular chain entanglements in HBPS.

UR - http://www.scopus.com/inward/record.url?scp=69849086865&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=69849086865&partnerID=8YFLogxK

U2 - 10.1016/j.polymer.2009.08.029

DO - 10.1016/j.polymer.2009.08.029

M3 - Article

VL - 50

SP - 4868

EP - 4875

JO - Polymer

JF - Polymer

SN - 0032-3861

IS - 20

ER -