The poly(L-lactic acid) (PLLA) has potential medical usage such as drug delivery since it can degrade into bioabsorbable products in physiological environments, while the degradation is affected by its crystallites. In this paper, the effects of film formation method and annealing on the crystallites formed in PLLA films are investigated. The films are made through solvent casting and spin coating, and subsequent annealing is conducted. The resulting morphology, molecular order, conformation, and intermolecular interaction are examined using optical microscopy, wide-angle X-ray diffraction, and Fourier transform infrared spectroscopy. It is observed that solvent casting produces category 1 spherulites while annealing the spin coated films leads to spherulites of category 2. The crystal structure of the two kinds of films also shows distinct features. The results enable better understanding of the crystallites in PLLA, which is essential for its medical application.

References

1.
Nampoothiri
,
K. M.
,
Nair
,
N. R.
, and
John
,
R. P.
,
2010
, “
An Overview of the Recent Developments in Polylactide (PLA) Research
,”
Bioresour. Technol.
,
101
, pp.
8493
8501
.10.1016/j.biortech.2010.05.092
2.
Tsuji
,
H.
, and
Ikada
,
Y.
,
1998
, “
Properties and Morphology of Poly(L-Lactide). II. Hydrolysis in Alkaline Solution
,”
J. Polym. Sci., Part A: Polym. Chem.
,
36
, pp.
59
66
.10.1002/(SICI)1099-0518(19980115)36:1<59::AID-POLA9>3.0.CO;2-X
3.
Tsuji
,
H.
, and
Ikada
,
Y.
,
1995
, “
Properties and Morphology of Poly(L-Lactide). 1. Annealing Condition Effects on Properties and Morphologies of Poly(L-Lactide)
,”
Polymer
,
36
(
14
), pp.
2709
2716
.10.1016/0032-3861(95)93647-5
4.
Bhatla
,
A.
, and
Yao
,
Y. L.
,
2009
, “
Effect of Laser Surface Modification on the Crystallinity of Poly(L-Lactic Acid)
,”
J. Manuf. Sci. Eng.
,
131
, p.
051004
.10.1115/1.3039519
5.
Li
,
H.
,
Nie
,
W.
,
Deng
,
C.
,
Chen
,
X.
, and
Ji
,
X.
,
2009
, “
Crystalline Morphology of Poly(L-Lactic Acid) Thin Films
,”
Eur. Polym. J.
,
45
, pp.
123
130
.10.1016/j.eurpolymj.2008.10.008
6.
Norton
,
D. R.
, and
Keller
,
A.
,
1985
, “
The Spherulitic and Lamellar Morphology of Melt-Crystallized Isotactic Polypropylene
,”
Polymer
,
26
, pp.
704
716
.10.1016/0032-3861(85)90108-9
7.
Takeda
,
H.
,
Nakashima
,
C.
, and
Nasu
,
N.
,
2005
, “
Studies on Structure of Poly(ε-L-Lysine) Spherulite Grown From Solution
,”
Sen'i Gakkaishi
,
61
, pp.
61
66
.10.2115/fiber.61.61
8.
Zhao
,
J.
,
Qiu
,
J.
,
Niu
,
Y.
, and
Wang
,
Z.
,
2009
, “
Evolutions of Morphology and Crystalline Ordering Upon Annealing of Quenched Isotactic Polypropylene
,”
J. Polym. Sci., Part B: Polym. Phys.
,
47
, pp.
1703
1712
.10.1002/polb.21773
9.
Su
,
C. H.
,
Jeng
,
U.
,
Chen
,
S. H.
,
Lin
,
S. J.
,
Wu
,
W. R.
,
Chuang
,
W.-T.
,
Tsai
,
J. C.
, and
Su
,
A. C.
,
2009
, “
Nanograin Evolution in Cold Crystallization of Syndiotactic Polystyrene as Illustrated via In-Situ Small/Wide Angle X-Ray Scattering and Differential Scanning Calorimetry
,”
Macromolecules
,
42
, pp.
6656
6664
.10.1021/ma900537c
10.
Hsu
,
C. C.
,
Geil
,
P. H.
,
Miyaji
,
H.
, and
Asai
,
K.
,
1986
, “
Structure and Properties of Polypropylene Crystallized from the Glassy State
,”
J. Polym. Sci. B
,
24
, pp.
2379
2401
.10.1002/polb.1986.090241018
11.
Ogawa
,
T.
,
Miyaji
,
H.
, and
Asai
,
K.
,
1985
, “
Nodule Structure of Polypropylene
,”
J. Phys. Soc. Jpn.
,
54
(
10
), pp.
3668
3670
.10.1143/JPSJ.54.3668
12.
Bassett
,
D. C.
,
Olley
,
R. H.
, and
Al Raheil
,
I. A. M.
,
1988
, “
On Crystallization Phenomena in PEEK
,”
Polymer
,
29
, pp.
1745
1754
.10.1016/0032-3861(88)90386-2
13.
Gao
,
X.
,
Hou
,
W.
,
Zhou
,
J.
,
Li
,
L.
, and
Zhao
,
L.
,
2004
, “
Relationships Between the Crystal Structures and the Multiple Melting Behaviors of Poly(Ethylene 2,6-Naphthalate)
,”
Macromol. Mater. Eng.
,
289
, pp.
174
180
.10.1002/mame.200300257
14.
Ivanov
,
D. A.
, and
Jonas
,
A. M.
,
1998
, “
Isothermal Growth and Reorganization upon Heating of a Single Poly(Aryl-Ether-Ether-Ketone) (PEEK) Spherulite, as Imaged by Atomic Force Microscopy
,”
Macromolecules
,
31
, pp.
4546
4550
.10.1021/ma961549e
15.
Pluta
,
M.
, and
Galeski
,
A.
,
2002
, “
Crystalline and Supermolecular Structure of Polylactide in Relation to the Crystallization Method
,”
J. Appl. Polym. Sci.
,
86
, pp.
1386
1395
.10.1002/app.11280
16.
Kobayashi
,
J.
,
Asahi
,
T.
,
Ichiki
,
M.
,
Oikawa
,
A.
,
Suzuki
,
H.
,
Watanabe
,
T.
,
Fukada
,
E.
, and
Shikinami
,
Y.
,
1995
, “
Structural and Optical Properties of Poly Lactic Acids
,”
J. Appl. Phys.
77
(
7
), pp.
2957
2973
.10.1063/1.358712
17.
Miyata
,
T.
, and
Masuko
,
T.
,
1997
, “
Morphology of Poly(L-Lactide) Solution-Grown Crystals
,”
Polymer
,
38
(
16
), pp.
4003
4009
.10.1016/S0032-3861(96)00987-1
18.
Sasaki
,
S.
, and
Asakura
,
T.
,
2003
, “
Helix Distortion and Crystal Structure of the α-Form of Poly(L-Lactide)
,”
Macromolecule
,
36
, pp.
8385
8390
.10.1021/ma0348674
19.
Davis
,
G. T.
,
Eby
,
R. K.
, and
Martin
,
G. M.
,
1968
, “
Variations of the Unit-Cell Dimensions of Polyethylene: Effect of Crystallization Conditions, Annealing, and Deformation
,”
J. Appl. Phys.
,
39
(
11
), pp.
4973
4981
.10.1063/1.1655895
20.
Kikkawa
,
Y.
,
Abe
,
H.
,
Iwata
,
T.
,
Inoue
,
Y.
, and
Doi
,
Y.
,
2002
, “
Crystallization, Stability, and Enzymatic Degradation of Poly(L-Lactide) Thin Film
,”
Biomacromolecules
,
3
(
2
), pp.
350
356
.10.1021/bm015623z
21.
Imai
,
M.
,
Mori
,
K.
,
Mizukami
,
T.
,
Kaji
,
K.
, and
Kanaya
,
T.
,
1992
, “
Structural Formation of Poly (Ethylene Terephthalate) During the Induction Period of Crystallization: 1. Ordered Structure Appearing Before Crystal Nucleation
,”
Polymer
,
33
(
21
), pp.
4451
4456
.10.1016/0032-3861(92)90399-H
22.
Schultz
,
J. M.
,
2001
,
Polymer Crystallization: The Development of Crystalline Order in Thermoplastic Polymers
,
Oxford University
,
New York
, Chaps. IV and X.
23.
Doi
,
M.
, and
Edwards
,
S. F.
,
1988
,
The Theory of Polymer Dynamics
,
Oxford University
,
New York
, Chaps. II and V.
24.
Cotton
,
J. P.
,
Nierlich
,
M.
,
Boue
,
F.
,
Daoud
,
M.
,
Farnoux
,
B.
,
Jannink
,
G.
,
Duplessix
,
R.
, and
Picot
,
C.
,
1976
, “
Experimental Determination of the Temperature-Concentration Diagram of Flexible Polymer Solutions by Neutron Scattering
,”
J. Chem. Phys.
,
65
(
3
), pp.
1101
1108
.10.1063/1.433172
25.
Akcasu
,
A. Z.
, and
Han
,
C. C.
,
1979
, “
Molecular Weight and Temperature Dependence of Polymer Dimensions in Solution
,”
Macromolecules
,
12
(
2
), pp.
276
280
.10.1021/ma60068a022
26.
De Gennes
,
P. G.
,
1971
, “
Reptation of a Polymer Chain in the Presence of Fixed Obstacles
,”
J. Chem. Phys.
,
55
(
2
), pp.
572
579
.10.1063/1.1675789
27.
Menczel
,
J.
, and
Wunderlich
,
B.
,
1981
, “
Heat Capacity Hysteresis of Semicrystalline Macromolecular Glasses
,”
J. Polym. Sci., Polym. Lett. Ed.
,
19
, pp.
261
264
.10.1002/pol.1981.130190506
28.
Granasy
,
L.
,
Pusztai
,
T.
,
Tegze
,
G.
,
Warren
,
J. A.
, and
Douglas
,
J. F.
,
2005
, “
Growth and Form of Spherulites
,”
Phys. Rev. E
,
72
, p.
011605
.10.1103/PhysRevE.72.011605
29.
Li
,
L.
,
Chan
,
C.-M.
,
Yeung
,
K. L.
,
Li
,
J.-X.
,
Ng
,
K.-M.
, and
Lei
,
Y.
,
2001
, “
Direct Observation of Growth of Lamellae and Spherulites of a Semicrystalline Polymer by AFM
,”
Macromolecules
,
34
, pp.
316
325
.10.1021/ma000273e
30.
Schindler
,
A.
, and
Harper
,
D.
,
1979
, “
Polylactide. II. Viscosity-Molecular Weight Relationships and Unperturbed Chain Dimensions
,”
J. Polym. Sci., Polym. Chem. Ed.
,
17
, pp.
2593
2599
.10.1002/pol.1979.170170831
31.
Frank
,
C. W.
,
Rao
,
V.
,
Despotopoulou
,
M. M.
,
Pease
,
R. F. W.
,
Hinsberg
,
W. D.
,
Miller
,
R. D.
, and
Rabolt
,
J. F.
,
1996
, “
Structure in Thin and Ultrathin Spin-Cast Polymer Films
,”
Science
,
273
, pp.
912
915
.10.1126/science.273.5277.912
32.
Lanceley
,
H. A.
, and
Sharples
,
A.
,
1966
, “
A Kinetic Study of Polymer Crystallization From Solution
,”
Die Makromol. Chem.
,
94
, pp.
30
41
.10.1002/macp.1966.020940104
33.
Zhang
,
J.
,
Liang
,
Y.
,
Yan
,
J.
, and
Lou
,
J.
,
2007
, “
Study of the Molecular Weight Dependence of Glass Transition Temperature for Amorphous Poly(L-Lactide) by Molecular Dynamics Simulation
,”
Polymer
,
48
, pp.
4900
4905
.10.1016/j.polymer.2007.06.030
34.
Maillard
,
D.
, and
Prud'homme
,
R. E.
,
2008
, “
The Crystallization of Ultrathin Films of Polylactides-Morphologies and Transitions
,”
Can. J. Chem.
,
86
, pp.
556
563
.10.1139/v08-045
35.
Narladkar
,
A.
,
Balnois
,
E.
,
Vignaud
,
G.
, and
Grohens
,
Y.
,
2008
, “
Difference in Glass Transition Behavior Between Semi Crystalline and Amorphous Poly(Lactic Acid) Thin Films
,”
Macromol. Symp.
,
273
, pp.
146
152
.10.1002/masy.200851321
36.
Strobl
,
G.
,
2000
, “
From the Melt via Mesomorphic and Granular Crystalline Layers to Lamellar Crystallites: A Major Route Followed in Polymer Crystallization?
,”
Eur. Phys. J. E
,
3
, pp.
165
183
.10.1007/s101890070030
37.
Wunderlich
,
B.
,
1976
,
Macromolecular Physics
, Vol.
2
,
Academic
,
New York
, Chap. V.
38.
Alexander
,
L. E.
,
1969
,
X-Ray Diffraction Methods in Polymer Science
,
John Wiley & Sons
,
New York
, Chap. I.
39.
Campbell
,
D.
,
Pethrick
,
R. A.
, and
White
,
J. R.
,
2000
,
Polymer Characterization
, 2nd ed.,
Stanley Thornes
,
Cheltenham
.
40.
Wang
,
Y.
,
Funari
,
S. S.
, and
Mano
,
J. F.
,
2006
, “
Influence of Semicrystalline Morphology on the Glass Transition of Poly(L-Lactic Acid)
,”
Macromol. Chem. Phys.
,
207
, pp.
1262
1271
.10.1002/macp.200600114
41.
Sarasua
,
J.-R.
,
Zuza
,
E.
,
Imaz
,
N.
, and
Meaurio
,
E.
,
2008
, “
Crystallinity and Crystalline Confinement of the Amorphous Phase in Polylactides
,”
Macromol. Symp.
,
272
, pp.
81
86
.10.1002/masy.200851211
42.
Kister
,
G.
,
Cassanas
,
G.
, and
Vert
,
M.
,
1998
, “
Effects of Morphology, Conformation and Configuration on the IR and Raman Spectra of Various Poly(Lactic Acid)s
,”
Polymer
,
39
(
2
), pp.
267
273
.10.1016/S0032-3861(97)00229-2
43.
Meaurio
,
E.
,
Zuza
,
E.
,
Lopez-Rodrıguez
,
N.
, and
Sarasua
,
J. R.
,
2006
, “
Conformational Behavior of Poly(L-Lactide) Studied by Infrared Spectroscopy
,”
J. Phys. Chem.
,
110
, pp.
5790
5800
.10.1021/jp055203u
44.
Kang
,
S.
,
Hsu
,
S. L.
,
Stidham
,
H. D.
,
Smith
,
P. B.
,
Leugers
,
M. A.
, and
Yang
,
X.
,
2001
, “
A Spectroscopic Analysis of Poly(Lactic Acid) Structure
,”
Macromolecules
,
34
, pp.
4542
4548
.10.1021/ma0016026
45.
Smith
,
B.
,
1999
,
Infrared Spectral Interpretation: A Systematic Approach
,
CRC Press
,
Boca Raton, FL
, Chap. I.
46.
Roylance
,
D. K.
, and
DeVries
,
K. L.
,
1971
, “
Determination of Atomic Stress Distribution in Oriented Polypropylene by Infrared Spectroscopy
,”
Polym. Lett.
,
9
, pp.
443
447
.10.1002/pol.1971.110090607
47.
Croll
,
S. G.
,
1979
, “
The Origin of Residual Internal Stress in Solvent-Cast Thermoplastic Coatings
,”
J. Appl. Polym. Sci.
,
23
, pp.
847
858
.10.1002/app.1979.070230319
48.
Vorotilov
,
K.
,
Petrovsky
,
V.
, and
Vasiljev
,
V.
,
1995
, “
Spin Coating Process of Sol-Gel Silicate Films Deposition: Effect of Spin Speed and Processing Temperature
,”
J. Sol-Gel Sci. Technol.
,
5
, pp.
173
183
.10.1007/BF00487014
49.
Chang
,
C.-C.
,
Wei
,
K.-H.
, and
Chen
,
W.-C.
,
2003
, “
Spin-Coating of Polyimide-Silica Hybrid Optical Thin Films
,”
J. Electrochem. Soc.
,
150
(
8
), pp.
F147
F150
.10.1149/1.1586925
You do not currently have access to this content.