Composition dependence of phase instability and cloud point in solution- blended mixtures of polystyrene with poly(cyclohexyl methacrylate)

Fan Hwei Jang, Eamor Woo

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Composition dependence of phase behavior in the mixture system of polystyrene (PS) with poly(cyclohexthyl methacrylate) (PCHMA) was examined in details using differential scanning calorimetry, optical and scanning electron microscopy, and infrared spectroscopy. This study shows that the `transparent' blends of PS/PCHMA with an apparent single Tg, having been thought to be miscible in earlier reports, actually displayed micro-heterogeneity domains of about 100-300 angstroms. It is thus not appropriate to assess miscibility to the optically clear blends of PS/PCHMA; however, partial miscibility does exist. The PCHMA-rich (PCHMA>70 wt%) compositions are indeed miscible but the PS-rich compositions are only partially miscible with sub-micron discrete phase domains beyond detection limit of optical microscopy. The proximity of the Tgs also prevented that the thermal transition of the micro phase domains in the PS-rich blends being resolved. The criterion of single Tg commonly employed in assessing phase behavior should be used with extra precaution in cases where micro-heterogeneity exists, whose ambiguity is even compounded in cases where the Tgs of the constituent polymers are close. The FT-ir result indicates that intermolecular interactions are weak or non-specific for the PCHMA-PS pair.

Original languageEnglish
Pages (from-to)2231-2237
Number of pages7
Journalpolymer
Volume40
Issue number9
DOIs
Publication statusPublished - 1999 Jan 1

Fingerprint

Methacrylates
Polystyrenes
Chemical analysis
Phase behavior
Solubility
Optical microscopy
Differential scanning calorimetry
Infrared spectroscopy
Polymers
Scanning electron microscopy

All Science Journal Classification (ASJC) codes

  • Organic Chemistry
  • Polymers and Plastics

Cite this

@article{1b49c00d2f5e471f8bbe724135c6079f,
title = "Composition dependence of phase instability and cloud point in solution- blended mixtures of polystyrene with poly(cyclohexyl methacrylate)",
abstract = "Composition dependence of phase behavior in the mixture system of polystyrene (PS) with poly(cyclohexthyl methacrylate) (PCHMA) was examined in details using differential scanning calorimetry, optical and scanning electron microscopy, and infrared spectroscopy. This study shows that the `transparent' blends of PS/PCHMA with an apparent single Tg, having been thought to be miscible in earlier reports, actually displayed micro-heterogeneity domains of about 100-300 angstroms. It is thus not appropriate to assess miscibility to the optically clear blends of PS/PCHMA; however, partial miscibility does exist. The PCHMA-rich (PCHMA>70 wt{\%}) compositions are indeed miscible but the PS-rich compositions are only partially miscible with sub-micron discrete phase domains beyond detection limit of optical microscopy. The proximity of the Tgs also prevented that the thermal transition of the micro phase domains in the PS-rich blends being resolved. The criterion of single Tg commonly employed in assessing phase behavior should be used with extra precaution in cases where micro-heterogeneity exists, whose ambiguity is even compounded in cases where the Tgs of the constituent polymers are close. The FT-ir result indicates that intermolecular interactions are weak or non-specific for the PCHMA-PS pair.",
author = "Jang, {Fan Hwei} and Eamor Woo",
year = "1999",
month = "1",
day = "1",
doi = "10.1016/S0032-3861(98)00452-2",
language = "English",
volume = "40",
pages = "2231--2237",
journal = "Polymer",
issn = "0032-3861",
publisher = "Elsevier BV",
number = "9",

}

Composition dependence of phase instability and cloud point in solution- blended mixtures of polystyrene with poly(cyclohexyl methacrylate). / Jang, Fan Hwei; Woo, Eamor.

In: polymer, Vol. 40, No. 9, 01.01.1999, p. 2231-2237.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Composition dependence of phase instability and cloud point in solution- blended mixtures of polystyrene with poly(cyclohexyl methacrylate)

AU - Jang, Fan Hwei

AU - Woo, Eamor

PY - 1999/1/1

Y1 - 1999/1/1

N2 - Composition dependence of phase behavior in the mixture system of polystyrene (PS) with poly(cyclohexthyl methacrylate) (PCHMA) was examined in details using differential scanning calorimetry, optical and scanning electron microscopy, and infrared spectroscopy. This study shows that the `transparent' blends of PS/PCHMA with an apparent single Tg, having been thought to be miscible in earlier reports, actually displayed micro-heterogeneity domains of about 100-300 angstroms. It is thus not appropriate to assess miscibility to the optically clear blends of PS/PCHMA; however, partial miscibility does exist. The PCHMA-rich (PCHMA>70 wt%) compositions are indeed miscible but the PS-rich compositions are only partially miscible with sub-micron discrete phase domains beyond detection limit of optical microscopy. The proximity of the Tgs also prevented that the thermal transition of the micro phase domains in the PS-rich blends being resolved. The criterion of single Tg commonly employed in assessing phase behavior should be used with extra precaution in cases where micro-heterogeneity exists, whose ambiguity is even compounded in cases where the Tgs of the constituent polymers are close. The FT-ir result indicates that intermolecular interactions are weak or non-specific for the PCHMA-PS pair.

AB - Composition dependence of phase behavior in the mixture system of polystyrene (PS) with poly(cyclohexthyl methacrylate) (PCHMA) was examined in details using differential scanning calorimetry, optical and scanning electron microscopy, and infrared spectroscopy. This study shows that the `transparent' blends of PS/PCHMA with an apparent single Tg, having been thought to be miscible in earlier reports, actually displayed micro-heterogeneity domains of about 100-300 angstroms. It is thus not appropriate to assess miscibility to the optically clear blends of PS/PCHMA; however, partial miscibility does exist. The PCHMA-rich (PCHMA>70 wt%) compositions are indeed miscible but the PS-rich compositions are only partially miscible with sub-micron discrete phase domains beyond detection limit of optical microscopy. The proximity of the Tgs also prevented that the thermal transition of the micro phase domains in the PS-rich blends being resolved. The criterion of single Tg commonly employed in assessing phase behavior should be used with extra precaution in cases where micro-heterogeneity exists, whose ambiguity is even compounded in cases where the Tgs of the constituent polymers are close. The FT-ir result indicates that intermolecular interactions are weak or non-specific for the PCHMA-PS pair.

UR - http://www.scopus.com/inward/record.url?scp=0001486442&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001486442&partnerID=8YFLogxK

U2 - 10.1016/S0032-3861(98)00452-2

DO - 10.1016/S0032-3861(98)00452-2

M3 - Article

VL - 40

SP - 2231

EP - 2237

JO - Polymer

JF - Polymer

SN - 0032-3861

IS - 9

ER -