Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer

Pratima Rangarajan, Richard Alan Register, Lewis J. Fetters, Wim Bras, Steven Naylor, Anthony J. Ryan

Research output: Contribution to journalArticle

100 Citations (Scopus)

Abstract

Microphase separation and subsequent crystallization are studied in an ethylene/head-to-head propylene (E/hhP) diblock copolymer using time-resolved small- and wide-angle X-ray scattering (SAXS and WAXS). When the sample is cooled from the melt, the SAXS data show a broad maximum due to correlation-hole scattering, which is replaced by a single sharp Bragg reflection due to the melt microstructure. During subsequent crystallization, two higher-order reflections grow concurrently. Thus, for similar quench depths below the microphase separation transition (TMST) and the melting temperature (Tm) respectively, microstructures representative of weak and strong segregation are observed. The second- and third-order reflections are superimposed on an intense broad maximum arising from the heterogeneity within the semicrystalline E domains. The second- and third-order SAXS peaks and the broad maximum on which they are superimposed, none of which are visible prior to crystallization, grow in parallel with the development of crystallinity at the unit cell level observed by WAXS. The overall domain periodicity d increases during crystallization but its value is path dependent and varies with the cooling rate from the melt.

Original languageEnglish (US)
Pages (from-to)4932-4938
Number of pages7
JournalMacromolecules
Volume28
Issue number14
DOIs
StatePublished - Jul 1 1995

Fingerprint

Polyolefins
Crystallization
Block copolymers
Microphase separation
Microstructure
X ray scattering
Propylene
Melting point
Ethylene
Scattering
Cooling
PL 732

All Science Journal Classification (ASJC) codes

  • Materials Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Organic Chemistry

Cite this

Rangarajan, P., Register, R. A., Fetters, L. J., Bras, W., Naylor, S., & Ryan, A. J. (1995). Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer. Macromolecules, 28(14), 4932-4938. https://doi.org/10.1021/ma00118a022
Rangarajan, Pratima ; Register, Richard Alan ; Fetters, Lewis J. ; Bras, Wim ; Naylor, Steven ; Ryan, Anthony J. / Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer. In: Macromolecules. 1995 ; Vol. 28, No. 14. pp. 4932-4938.
@article{561c559c4ce34977abd7b0c212f573b1,
title = "Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer",
abstract = "Microphase separation and subsequent crystallization are studied in an ethylene/head-to-head propylene (E/hhP) diblock copolymer using time-resolved small- and wide-angle X-ray scattering (SAXS and WAXS). When the sample is cooled from the melt, the SAXS data show a broad maximum due to correlation-hole scattering, which is replaced by a single sharp Bragg reflection due to the melt microstructure. During subsequent crystallization, two higher-order reflections grow concurrently. Thus, for similar quench depths below the microphase separation transition (TMST) and the melting temperature (Tm) respectively, microstructures representative of weak and strong segregation are observed. The second- and third-order reflections are superimposed on an intense broad maximum arising from the heterogeneity within the semicrystalline E domains. The second- and third-order SAXS peaks and the broad maximum on which they are superimposed, none of which are visible prior to crystallization, grow in parallel with the development of crystallinity at the unit cell level observed by WAXS. The overall domain periodicity d increases during crystallization but its value is path dependent and varies with the cooling rate from the melt.",
author = "Pratima Rangarajan and Register, {Richard Alan} and Fetters, {Lewis J.} and Wim Bras and Steven Naylor and Ryan, {Anthony J.}",
year = "1995",
month = "7",
day = "1",
doi = "https://doi.org/10.1021/ma00118a022",
language = "English (US)",
volume = "28",
pages = "4932--4938",
journal = "Macromolecules",
issn = "0024-9297",
publisher = "American Chemical Society",
number = "14",

}

Rangarajan, P, Register, RA, Fetters, LJ, Bras, W, Naylor, S & Ryan, AJ 1995, 'Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer', Macromolecules, vol. 28, no. 14, pp. 4932-4938. https://doi.org/10.1021/ma00118a022

Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer. / Rangarajan, Pratima; Register, Richard Alan; Fetters, Lewis J.; Bras, Wim; Naylor, Steven; Ryan, Anthony J.

In: Macromolecules, Vol. 28, No. 14, 01.07.1995, p. 4932-4938.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer

AU - Rangarajan, Pratima

AU - Register, Richard Alan

AU - Fetters, Lewis J.

AU - Bras, Wim

AU - Naylor, Steven

AU - Ryan, Anthony J.

PY - 1995/7/1

Y1 - 1995/7/1

N2 - Microphase separation and subsequent crystallization are studied in an ethylene/head-to-head propylene (E/hhP) diblock copolymer using time-resolved small- and wide-angle X-ray scattering (SAXS and WAXS). When the sample is cooled from the melt, the SAXS data show a broad maximum due to correlation-hole scattering, which is replaced by a single sharp Bragg reflection due to the melt microstructure. During subsequent crystallization, two higher-order reflections grow concurrently. Thus, for similar quench depths below the microphase separation transition (TMST) and the melting temperature (Tm) respectively, microstructures representative of weak and strong segregation are observed. The second- and third-order reflections are superimposed on an intense broad maximum arising from the heterogeneity within the semicrystalline E domains. The second- and third-order SAXS peaks and the broad maximum on which they are superimposed, none of which are visible prior to crystallization, grow in parallel with the development of crystallinity at the unit cell level observed by WAXS. The overall domain periodicity d increases during crystallization but its value is path dependent and varies with the cooling rate from the melt.

AB - Microphase separation and subsequent crystallization are studied in an ethylene/head-to-head propylene (E/hhP) diblock copolymer using time-resolved small- and wide-angle X-ray scattering (SAXS and WAXS). When the sample is cooled from the melt, the SAXS data show a broad maximum due to correlation-hole scattering, which is replaced by a single sharp Bragg reflection due to the melt microstructure. During subsequent crystallization, two higher-order reflections grow concurrently. Thus, for similar quench depths below the microphase separation transition (TMST) and the melting temperature (Tm) respectively, microstructures representative of weak and strong segregation are observed. The second- and third-order reflections are superimposed on an intense broad maximum arising from the heterogeneity within the semicrystalline E domains. The second- and third-order SAXS peaks and the broad maximum on which they are superimposed, none of which are visible prior to crystallization, grow in parallel with the development of crystallinity at the unit cell level observed by WAXS. The overall domain periodicity d increases during crystallization but its value is path dependent and varies with the cooling rate from the melt.

UR - http://www.scopus.com/inward/record.url?scp=0029634510&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029634510&partnerID=8YFLogxK

U2 - https://doi.org/10.1021/ma00118a022

DO - https://doi.org/10.1021/ma00118a022

M3 - Article

VL - 28

SP - 4932

EP - 4938

JO - Macromolecules

JF - Macromolecules

SN - 0024-9297

IS - 14

ER -

Rangarajan P, Register RA, Fetters LJ, Bras W, Naylor S, Ryan AJ. Crystallization of a Weakly Segregated Polyolefin Diblock Copolymer. Macromolecules. 1995 Jul 1;28(14):4932-4938. https://doi.org/10.1021/ma00118a022