Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change in chain folding directions

doi:10.1007/s11705-009-0002-2

Front Chem Eng Chin

2009, Vol. 3

Issue (1) : 26-32 https://doi.org/10.1007/s11705-009-0002-2

RESEARCH ARTICLE

Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change in chain folding directions

Motoi YAMASHITA(

)

College of pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan

Download: PDF(224 KB) HTML
Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks

Abstract

Lamellar crystal thickness l_c of isotactic polybutene-1 (it-PB1) have been investigated for crystallization in the melt over a wide range of crystallization temperature T from 40°C to 90°C by small angle X-ray scattering experiments and density measurements. The crystal thickness l_c demonstrates two linear dependences on inverse supercooling and a transition from one dependence to the other has been observed around T = 65°C. Each of the two dependences obeys the nucleation theory in the high and low supercooling ranges, respectively. Chain folding free energy q determined from the low supercooling range is larger than that determined from the high supercooling range. Possible mechanisms for the transition are discussed taking account of entropy of chain folding directions.

Keywords isotactic polybutene-1 tetragonal phase crystal thickness melt growth chain folding small angle X-ray scattering nucleation theory end surface free energy

Corresponding Author(s): YAMASHITA Motoi,Email:motoi-y@fc.ritsumei.ac.jp

Issue Date: 05 March 2009

Cite this article:

Motoi YAMASHITA. Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change in chain folding directions[J]. Front Chem Eng Chin, 2009, 3(1): 26-32.

URL:

https://academic.hep.com.cn/fcse/EN/10.1007/s11705-009-0002-2
https://academic.hep.com.cn/fcse/EN/Y2009/V3/I1/26

Fig.1 WAXD profiles of -PB1 crystallized at 40°C, 65°C and 90°C plotted against the modulus of the scattering vector . ( = 4πsin, is half the scattering angle, is the wave length used. The diffraction intensity data were taken from Ref. [].) The profiles for samples as crystallized and aged are plotted. Peaks shown in the plots of the as crystallized samples are indexed with 200, 220, 213 reflections of the tetragonal phase. The peaks exhibited in the plots of the aged samples are indexed with 110, 300, 220 reflections of the trigonal phase

Fig.2 Crystallinity plotted against crystallization temperature (The crystallinity data were taken from Ref. [] )

Fig.3 Lamellar crystal thickness and the first-order long period as functions of crystallization temperature . (The data were taken from Ref. [].) The and values are 171 ? and 334 ?, respectively, at 85°C. These values are roughly in agreement with the values of the as crystallized tetragonal crystals reported by Fu et al., = 150 ? and = 300 ? []

Fig.4 Lamellar crystal thickness as a function of the inverse supercooling, (Taken from Ref. [] )

Fig.5 (a) Chain folding directions on facetted crystal growth front. Since chain re-entrant sites are restricted to the 2 neighboring stems along the (100) growth front, there are only two combinations of chain folding-in and chain folding-out directions shown as A and B. A schematic illustration of possible chain re-entrant sites in facetted crystals seen from the crystalline -axis is shown in the inset. (b) Chain folding on kinetically roughened growth front. Since the growth front is rough, chain re-entrant sites can be neighboring 8 stems. Chain can fold-in from neighboring 8 stems and can fold-out into neighboring 7 stems. The number of possible combinations of chain folding-in and folding-out directions is 8×7=56. A schematic illustration of possible chain re-entrant sites in kinetically roughened crystals seen from the crystalline -axis is shown in the inset

Fig.6 Schematic illustrations of chain re-entrant sites (a) in kinetically roughened crystals and (b) in facetted crystals seen from the crystalline -axis when a chain re-entry can skip a stem. Non-adjacent sites are indicated by shadowed regions

1	Hoffman J D, Davis G T, Lauritzen J I Jr. Treatise on solid state chemistry. Hannay N B, Ed . New York: Plenum, 1976: 497–580
2	Hoffman J D, Miller R L. Kinetics of crystallization from the melt and chain folding in polyethylene fractions revisited: theory and experiment. Polymer , 1997, 38: 3151 doi: 10.1016/S0032-3861(97)00071-2
3	Yamashita M, Miyaji H, Izumi K, Hoshino A. Crystal growth of isotactic poly(butane-1) in the Melt. I. kinetic roughening. Polym J , 2004, 36: 226–237 doi: 10.1295/polymj.36.226
4	Yamashita M, Kato M. Lamellar crystal thickness transition of melt crystallized isotactic polybutene-1 observed by small-angle X-ray scattering. J Appl Cryst , 2007, 40: s650–655 doi: 10.1107/S0021889807011570
5	Turner-Jones A. Poly-l-butylene Type II crystalline form. J Polym Sci Pt B: Polym Lett , 1963, 1: 455–456 doi: 10.1002/pol.1963.110010815
6	Natta G, Corradini P, and Bassi I W. Crystal structure of isotactic poly(1-butene). Nuovo Cimento Suppl , 1960, 15: 52–67 doi: 10.1007/BF02731860
7	Miller R L. Polymer Handbook. 4th ed. Brandrup J, Immergut E H, Grulke E A, Ed. New York: Interscience Publishers, 1999: VI/1–70
8	Danusso F, Gianotti G. Isotactic poly-1-butene: formation and transformation of Modification 2. Macromol Chem , 1965, 61: 149–158 doi: 10.1002/macp.1965.020880110
9	Yamashita M, Kato M. Surface free energies of isotactic polybutene-1 tetragonal and trigonal crystals: the role of conformational entropy of side chains. J Appl Cryst , 2007, 40: s558–563 doi: 10.1107/S0021889807011259
10	RubinI D. Relative stabilities of polymorphs of polybutene-1 obtained from the melt. J Polym Sci , 1964, B2: 747–749
11	Kopp S, Wittmann J C, Lotz B. Phase II to phase I crystal transformation in polybutene-1 single crystals: a reinvestigation. J Mat Sci , 1994, 29: 6159–6166 doi: 10.1007/BF00354556
12	Fujiwara Y. II-I phase transformation of melt-crystallized oriented lamellae of polybutene-1 by shear deformation. Polym Bull , 1985, 13: 253–258 doi: 10.1007/BF00254659
13	Fu Q, Heck B, Strobl G, Thomann Y. A temperature- and molar mass-dependent change in the crystallization mechanism of poly(1-butene): transition from chain-folded to chain-extended crystallization? Macromolecules , 2001, 34: 2502 doi: 10.1021/ma0015875
14	Leute U, Dollhopf W. High pressure dilatometry on polybutene-1. Colloid Polym Sci , 1983, 261: 299–305 doi: 10.1007/BF01413935
15	Tashiro K, Saiani A, Miyashita S, Chatani Y, Tadokoro H. Crystal structure of unstable Form II of isotactic polybutene-1: structure anarysis by a combination of X-Ray imaging plate and computer simulation technique. Polym Prepr Jpn , 1998, 47: 3869
16	Yamashita M, Hoshino A, Kato M. Isotactic poly(butene-1) trigonal crystal growth in the melt. J Polym Sci Polym Phys Ed , 2007, 45: 684–697 doi: 10.1002/polb.21052
17	Yamashita M, Takahashi T. The effect of side chain entropy on polymer crystal surfaces-Surface free energies of isotactic polybutene-1 tetragonal and trigonal crystals. Kobunshi Ronbunshu , 2008, 65: 218–227 doi: 10.1295/koron.65.218
18	Yamashita M, Takahashi T. Melt crystallization of isotactic polybutene-1 trigonal form: the effect of side chain entropy on crystal growth kinetics.. Polym J , 2008, 40: 996–1004 doi: 10.1295/polymj.PJ2007196
19	Yamashita M, Ueno S. Direct melt crystal growth of isotactic polybutene-1 trigonal phase. Cryst Res Tech , 2007, 42: 1222–1227 doi: 10.1002/crat.200711009
20	Yamashita M. Direct crystal growth of isotactic polybutene-1 trigonal phase in the melt: in-situ observation. J Cryst Gro , 2008, 310: 1739–1743 doi: 10.1016/j.jcrysgro.2007.11.220
21	Yamashita M, Takahashi T. Kinetic roughening transition of isotactic polybutene-1 tetragonal crystals: disagreement between morphology and growth kinetics.. Polym J , 2008, 40: 1025–1030 doi: 10.1295/polymj.PJ2007209
22	Yamashita M, Takahashi T. Directional entropy of chain folding detected in chain folding free energies? Crystal thickness transition of isotactic polybutene-1 tetragonal phase.. Polym J , 2008, 40: 1010–1016 doi: 10.1295/polymj.PJ2007198

[1]	Motoi YAMASHITA. Kinetic roughening transition and missing regime transition of melt crystallized polybutene-1 tetragonal phase: growth kinetics analysis[J]. Front Chem Eng Chin, 2009, 3(2): 125-134.

Viewed

Full text

Abstract

Cited

Shared

Discussed