Time-resolved X-ray studies of structure development in poly(butylene terephthalate) during isothermal crystallization

被引:124
作者
Hsiao, BS [1 ]
Wang, ZG
Yeh, FJ
Gao, Y
Sheth, KC
机构
[1] SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA
[2] GE Co, Corp Res & Dev, Schenectady, NY 12309 USA
基金
美国国家科学基金会;
关键词
isothermal melt crystallization; PBT; SWAXS;
D O I
10.1016/S0032-3861(98)00573-4
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
Isothermal melt crystallization in poly(butylene terephthalate) (PBT) homopolymers and glass-fiber-filled composite was studied by time-resolved simultaneous small- and wide-angle X-ray scattering (SWAXS) methods using synchrotron radiation. During primary crystallization, both average long period and lamellar thickness exhibit a significant decrease. During secondary crystallization, the long period and lamellar thickness show a smaller decrease over a longer period of time, which is approximately linear with log time. Similar to other semicrystalline polymers, the morphology of PET formed during isothermal crystallization can be best described by a dual-lamellar stack model. In this model, primary lamellar stacks are formed first comprising thicker crystalline lamellae, whereas secondary lamellar stacks are formed later between the primary lamellar stacks (as observed by the small change of the interlayer amorphous thickness with time). In addition, no isothermal lamellar thickening is observed. From SWAXS measurements, the appearance of the SAXS peak appears to occur prior to WAXD crystal reflection peaks, suggesting that density fluctuations ape probably present before melt crystallization. The lamellar morphology and crystallization rate is found to be a function of molecular weight. The glass filler in the PET composites has no obvious effect on the lamellar structure, but it appears to act as a nucleating agent. (C) 1999 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:3515 / 3523
页数:9
相关论文
共 58 条
[1]  
[Anonymous], MACROMOLECULES
[2]  
BALTACALLEJA FJ, XRAY SCATTERING SYNT
[3]  
BERETON MG, 1978, POLYMER, V19, P17
[4]  
CERERE A, 1990, POLYMER, V31, P1239
[5]  
CHENG SZD, 1988, MAKROMOL CHEM, V189, P2443
[6]   GLASS-TRANSITION AND MELTING BEHAVIOR OF POLY(OXY-1,4-PHENYLENEOXY-1,4-PHENYLENECARBONYL-1,4-PHENYLENE) [J].
CHENG, SZD ;
CAO, MY ;
WUNDERLICH, B .
MACROMOLECULES, 1986, 19 (07) :1868-1876
[7]   A LASER-AIDED PREALIGNED PINHOLE COLLIMATOR FOR SYNCHROTRON X-RAYS [J].
CHU, B ;
HARNEY, PJ ;
LI, YJ ;
KUNG, LL ;
YEH, FJ ;
HSIAO, BS .
REVIEW OF SCIENTIFIC INSTRUMENTS, 1994, 65 (03) :597-602
[8]   SPECTROSCOPIC CHARACTERIZATION OF THE ALPHA-REVERSIBLE-BETA CRYSTALLINE PHASE-TRANSITION IN POLY(BUTYLENE TEREPHTHALATE) AND ITS COPOLYMERS WITH POLY(TETRAMETHYLENE OXIDE) [J].
DOBROVOLNYMARAND, E ;
HSU, SL ;
SHIH, CK .
MACROMOLECULES, 1987, 20 (05) :1022-1029
[9]  
EZQUERRA TA, 1997, PHYS REV E
[10]   Time-resolved SAXS, WAXS, and DSC study of melting of poly(aryl ether ether ketone) (PEEK) annealed from the amorphous state [J].
Fougnies, C ;
Damman, P ;
Dosiere, M ;
Koch, MHJ .
MACROMOLECULES, 1997, 30 (05) :1392-1399