Simulated Glass Transition in Free-Standing Thin Polystyrene Films

被引：51

作者：

Baljon, A. R. C. ^{[1
]}

Williams, S. ^{[1
]}

Balabaev, N. K. ^{[2
]}

Paans, F. ^{[3
]}

Hudzinskyy, D. ^{[3
,4
]}

Lyulin, A. V. ^{[3
]}

机构：

[1] San Diego State Univ, Dept Phys, San Diego, CA 92128 USA

[2] Inst Math Problems Biol, Pushchino 142290, Russia

[3] Tech Univ Eindhoven, Grp Theory Polymers & Soft Matter, Eindhoven Polymer Labs, NL-5600 MB Eindhoven, Netherlands

[4] Dutch Polymer Inst, NL-5600 AX Eindhoven, Netherlands

来源：

JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS | 2010年 / 48卷 / 11期

关键词：

glass transition; relaxation; simulations; thin films; MOLECULAR-DYNAMICS SIMULATION; POLYMER GLASSES; TEMPERATURE; BULK; MOBILITY; SURFACES; BEHAVIOR; CHAIN;

D O I：

10.1002/polb.22005

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

In this article, we investigate the glass transition in polystyrene melts and free-standing ultra-thin films by means of large-scale computer simulations. The transition temperatures are obtained from static (density) and dynamic (diffusion and orientational relaxation) measurements. As it turns out, the glass transition temperature of a 3 nm thin film is similar to 60 degrees K lower than that of the bulk. Local orientational mobility of the phenyl bonds is studied with the help of Legendre polynomials of the second-order P-2(t). The alpha and beta relaxation times are obtained from the spectral density of P-2(t). Our simulations reveal that interfaces affect alpha and beta-relaxation processes differently. The beta relaxation rate is faster in the center of the film than near a free surface; for the a relaxation rate, an opposite trend is observed. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1160-1167, 2010

引用

页码：1160 / 1167

页数：8

共 36 条

[1] Effects of confinement on material behaviour at the nanometre size scale [J].

Alcoutlabi, M ;

McKenna, GB .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2005, 17 (15) :R461-R524

[2] End-bridging Monte Carlo simulation of bulk and grafted amorphous polyethylene above and below the glass transition [J].

Alexiadis, Orestis ;

Mavrantzas, Vlasis G. ;

Khare, Rajesh ;

Beckers, Job ;

Baljon, Arlette R. C. .

MACROMOLECULES, 2008, 41 (03) :987-996

[3] Glass transition behavior of polymer films of nanoscopic dimensions [J].

Baljon, ARC ;

Van Weert, MHM ;

DeGraaff, RB ;

Khare, R .

MACROMOLECULES, 2005, 38 (06) :2391-2399

[4] Computer simulations of supercooled polymer melts in the bulk and in-confined geometry [J].

Baschnagel, J ;

Varnik, F .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2005, 17 (32) :R851-R953

[5] ELLIPSOMETRIC STUDY OF THE GLASS-TRANSITION AND THERMAL-EXPANSION COEFFICIENTS OF THIN POLYMER-FILMS [J].

BEAUCAGE, G ;

COMPOSTO, R ;

STEIN, RS .

JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS, 1993, 31 (03) :319-326

[6]

De Gennes P.-G, 1979, Scaling concepts in polymer physics

[7] Glass transitions in thin polymer films [J].

de Gennes, PG .

EUROPEAN PHYSICAL JOURNAL E, 2000, 2 (03) :201-203

[8] The distribution of glass-transition temperatures in nanoscopically confined glass formers [J].

Ellison, CJ ;

Torkelson, JM .

NATURE MATERIALS, 2003, 2 (10) :695-700

[9] Effect of free surfaces on the glass transition temperature of thin polymer films [J].

Forrest, JA ;

DalnokiVeress, K ;

Stevens, JR ;

Dutcher, JR .

PHYSICAL REVIEW LETTERS, 1996, 77 (10) :2002-2005

[10] The glass transition in thin polymer films [J].

Forrest, JA ;

Dalnoki-Veress, K .

ADVANCES IN COLLOID AND INTERFACE SCIENCE, 2001, 94 (1-3) :167-196

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