本研究藉由調整靜電紡絲操作參數製備靜電紡絲poly(L-lactide)(PLLA)纖維，探討靜電紡絲PLLA纖維之分子構型及結晶行為的變化。對於不同纖維直徑的系統，結晶性質隨著纖維尺寸而改變，相對於具有單一層狀結晶厚度分佈之PLLA粉末，纖維具有兩種層狀結晶厚度分佈，層狀結晶厚度較小的比例會隨纖維直徑增加而增加。此外，在電紡絲內的結晶形式隨著熱退火溫度不同主要分為α’和α形式，而α’和α形式之轉變與纖維尺寸之間無明顯關聯。對於不同溶劑比例製備之纖維而言，電紡絲纖維內的結晶形式除了α’和α結晶外，由氯仿:三氟乙醇= 95:5的高分子溶液製備之纖維在未經熱退火處理時為frustrated β相，經熱退火處理後，轉變為α’和α結晶。此外，在不同溫度和時間熱退火處理時，由氯仿:三氟乙醇= 95:5的高分子溶液製備之纖維，α’變成α晶體的轉變速率較氯仿:三氟乙醇= 60:40的高分子溶液製備之纖維快，此與分子鏈產生的糾纏程度有關。此外為了增加靜電紡絲纖維之結晶度，本研究添加少量的成核劑進行靜電紡絲，發現添加成核劑製備之纖維在不同熱退火溫度下，α’轉變成α結晶形式的速率較無添加成核劑製備之纖維快。利用非等溫結晶動力學分析，添加成核劑製備之纖維的結晶速率常數較大且結晶活化能較小，亦即添加成核劑之纖維結晶成核和成長速率較快。在水解降解測試中，含有成核劑之纖維的重量損失百分比皆高於未含成核劑之纖維，即添加成核劑製備纖維有助於改善PLLA降解速率緩慢之問題，此特性有助於其在藥物釋放領域的應用。

In this study, we investigated the conformational change and crystallization behavior of electrospun poly(L-lactide) (PLLA) fibers, which were prepared by manipulating various electrospinning parameters. The crystallization properties strongly depended on the fiber diameter. In contrast to the uniform crystal lamellae in bulk PLLA, crystals in PLLA fibers exhibited two populations of the lamellar thickness. The population of the crystal lamellae with a small thickness increased with an increase in the fiber diameter. In addition, the crystal structure of PLLA fibers exhibited α' and α forms, depending on the annealing temperature. The crystal transformation was independent of the fiber diameter. For the PLLA fibers fabricated using different solvents, the as-electrospun PLLA fibers exhibited a frustrated β phase when the fibers were prepared with 95:5 chloroform:trifluoroethanol. Subsequent thermal treatment resulted in the crystal transformation from the β phase to α' and α phases. When the PLLA fibers were subjected to thermal treatment, the transformation from α' to α crystals in the fibers fabricated with a high content of chloroform (95:5 chloroform:trifluoroethanol) was more rapidly than that in the fibers fabricated with a low content of chloroform (60:40 chloroform:trifluoroethanol). This behavior was attributed to the different degrees of entanglements of polymer chains in fibers. Furthermore, nucleating agents were added to the electrospun solution to promote the occurrence of crystallization. We found that the transformation from α' to α crystals increased when fibers were prepared with the addition of nucleating agents. According to the nonisothermal cold crystallization kinetics, the crystallization rate constant increased and the activation energy decreased for the fibers prepared with nucleating agents, indicating that nucleating agents facilitated nucleation and crystal growth. In the degradation test, the addition of nucleating agent increased the hydrolysis rate of fibers, which improved the slow degradation of PLLA. This behavior facilitates its use in the field of drug release.

[1] Storks, K. An electron diffraction examination of some linear high polymers. Journal of the American Chemical Society, 60 (8), 1753-1761, 1938.
[2] Milner, S. T. Polymer crystal–melt interfaces and nucleation in polyethylene. Soft Matter, 7 (6), 2909-2917, 2011.
[3] Hamdi, O.; Mighri, F.; Rodrigue, D. Piezoelectric cellular polymer films: Fabrication, properties and applications. AIMS Materials Science, 5, 845, 2018.
[4] Ergoz, E.; Fatou, J.; Mandelkern, L. Molecular weight dependence of the crystallization kinetics of linear polyethylene. I. Experimental results. Macromolecules, 5 (2), 147-157, 1972.
[5] Hay, J. N. Application of the modified avrami equations to polymer crystallisation kinetics. British Polymer Journal, 3 (2), 74-82, 1971.
[6] Shepilov, M.; Baik, D. Computer simulation of crystallization kinetics for the model with simultaneous nucleation of randomly-oriented ellipsoidal crystals. Journal of Non-Crystalline Solids, 171 (2), 141-156, 1994.
[7] Weinberg, M. C. On the analysis of non-isothermal thermoanalytic crystallization experiments. Journal of Non-Crystalline Solids, 127 (2), 151-158, 1991.
[8] Arshad, M. A.; Maaroufi, A. Relationship between Johnson–Mehl–Avrami and Šesták–Berggren models in the kinetics of crystallization in amorphous materials. Journal of Non-Crystalline Solids, 413, 53-58, 2015.
[9] Jeziorny, A. Parameters characterizing the kinetics of the non-isothermal crystallization of poly (ethylene terephthalate) determined by DSC. Polymer, 19 (10), 1142-1144, 1978.
[10] Supaphol, P.; Spruiell, J. Isothermal melt-and cold-crystallization kinetics and subsequent melting behavior in syndiotactic polypropylene: a differential scanning calorimetry study. Polymer, 42 (2), 699-712, 2001.
[11] Furushima, Y.; Schick, C.; Toda, A. Crystallization, recrystallization, and melting of polymer crystals on heating and cooling examined with fast scanning calorimetry. Polymer Crystallization, 1 (2), e10005, 2018.
[12] Supaphol, P. Application of the Avrami, Tobin, Malkin, and Urbanovici–Segal macrokinetic models to isothermal crystallization of syndiotactic polypropylene. Thermochimica Acta, 370 (1-2), 37-48, 2001.
[13] Di Lorenzo, M.; Silvestre, C. Non-isothermal crystallization of polymers. Progress in Polymer Science, 24 (6), 917-950, 1999.
[14] Liu, T.; Mo, Z.; Wang, S.; Zhang, H. Nonisothermal melt and cold crystallization kinetics of poly (aryl ether ether ketone ketone). Polymer Engineering & Science, 37 (3), 568-575, 1997.
[15] Ozawa, T. Kinetics of non-isothermal crystallization. Polymer, 12 (3), 150-158, 1971.
[16] De Santis, P.; Kovacs, A. Molecular conformation of poly (S‐lactic acid). Biopolymers: Original Research on Biomolecules, 6 (3), 299-306, 1968.
[17] Hoogsteen, W.; Postema, A.; Pennings, A.; Ten Brinke, G.; Zugenmaier, P. Crystal structure, conformation and morphology of solution-spun poly (L-lactide) fibers. Macromolecules, 23 (2), 634-642, 1990.
[18] Eling, B.; Gogolewski, S.; Pennings, A. Biodegradable materials of poly (l-lactic acid): 1. Melt-spun and solution-spun fibres. Polymer, 23 (11), 1587-1593, 1982.
[19] Puiggali, J.; Ikada, Y.; Tsuji, H.; Cartier, L.; Okihara, T.; Lotz, B. The frustrated structure of poly (L-lactide). Polymer, 41 (25), 8921-8930, 2000.
[20] Cartier, L.; Okihara, T.; Ikada, Y.; Tsuji, H.; Puiggali, J.; Lotz, B. Epitaxial crystallization and crystalline polymorphism of polylactides. Polymer, 41 (25), 8909-8919, 2000.
[21] Pan, P.; Zhu, B.; Kai, W.; Dong, T.; Inoue, Y. Polymorphic transition in disordered poly (L-lactide) crystals induced by annealing at elevated temperatures. Macromolecules, 41 (12), 4296-4304, 2008.
[22] Wasanasuk, K.; Tashiro, K.; Hanesaka, M.; Ohhara, T.; Kurihara, K.; Kuroki, R.; Tamada, T.; Ozeki, T.; Kanamoto, T. Crystal structure analysis of poly (l-lactic acid) α form on the basis of the 2-dimensional wide-angle synchrotron X-ray and neutron diffraction measurements. Macromolecules, 44 (16), 6441-6452, 2011.
[23] Zhang, J.; Duan, Y.; Sato, H.; Tsuji, H.; Noda, I.; Yan, S.; Ozaki, Y. Crystal modifications and thermal behavior of poly (L-lactic acid) revealed by infrared spectroscopy. Macromolecules, 38 (19), 8012-8021, 2005.
[24] Zhang, J.; Tashiro, K.; Tsuji, H.; Domb, A. J. Disorder-to-order phase transition and multiple melting behavior of poly (L-lactide) investigated by simultaneous measurements of WAXD and DSC. Macromolecules, 41 (4), 1352-1357, 2008.
[25] Wasanasuk, K.; Tashiro, K. Structural regularization in the crystallization process from the glass or melt of poly (l-lactic acid) viewed from the temperature-dependent and time-resolved measurements of FTIR and wide-angle/small-angle X-ray scatterings. Macromolecules, 44 (24), 9650-9660, 2011.
[26] Wang, H.; Zhang, J.; Tashiro, K. Phase Transition Mechanism of Poly (L-Lactic Acid) among the α, δ, and β Forms on the Basis of the Reinvestigated Crystal Structure of the β Form. Macromolecules, 50 (8), 3285-3300, 2017.
[27] Wang, H.; Keum, J. K.; Hiltner, A.; Baer, E.; Freeman, B.; Rozanski, A.; Galeski, A. Confined crystallization of polyethylene oxide in nanolayer assemblies. Science, 323 (5915), 757-760, 2009.
[28] Steinhart, M.; Göring, P.; Dernaika, H.; Prabhukaran, M.; Gösele, U.; Hempel, E.; Thurn-Albrecht, T. Coherent kinetic control over crystal orientation in macroscopic ensembles of polymer nanorods and nanotubes. Physical Review Letters, 97 (2), 027801, 2006.
[29] Michell, R. M.; Lorenzo, A. T.; Müller, A. J.; Lin, M.-C.; Chen, H.-L.; Blaszczyk-Lezak, I.; Martin, J.; Mijangos, C. The crystallization of confined polymers and block copolymers infiltrated within alumina nanotube templates. Macromolecules, 45 (3), 1517-1528, 2012.
[30] Martín, J.; Maiz, J.; Sacristan, J.; Mijangos, C. Tailored polymer-based nanorods and nanotubes by" template synthesis": From preparation to applications. Polymer, 53 (6), 1149-1166, 2012.
[31] He, W.-N.; Xu, J.-T. Crystallization assisted self-assembly of semicrystalline block copolymers. Progress in Polymer Science, 37 (10), 1350-1400, 2012.
[32] Samanta, P.; Liu, C.-L.; Nandan, B.; Chen, H.-L., Crystallization of polymers in confined space. In Crystallization in Multiphase Polymer Systems, Elsevier: 2018; pp 367-431.
[33] Guan, Y.; Liu, G.; Ding, G.; Yang, T.; Müller, A. J.; Wang, D. Enhanced crystallization from the glassy state of poly (L-lactic acid) confined in anodic alumina oxide nanopores. Macromolecules, 48 (8), 2526-2533, 2015.
[34] Nakagawa, S.; Marubayashi, H.; Nojima, S. Crystallization of polymer chains confined in nanodomains. European Polymer Journal, 70, 262-275, 2015.
[35] Zhu, L.; Cheng, S. Z.; Calhoun, B. H.; Ge, Q.; Quirk, R. P.; Thomas, E. L.; Hsiao, B. S.; Yeh, F.; Lotz, B. Crystallization temperature-dependent crystal orientations within nanoscale confined lamellae of a self-assembled crystalline− amorphous diblock copolymer. Journal of the American Chemical Society, 122 (25), 5957-5967, 2000.
[36] Masuda, H.; Fukuda, K. Ordered metal nanohole arrays made by a two-step replication of honeycomb structures of anodic alumina. Science, 268 (5216), 1466-1468, 1995.
[37] Steinhart, M., Supramolecular organization of polymeric materials in nanoporous hard templates. In Self-Assembled Nanomaterials II, Springer: 2008; pp 123-187.
[38] Shin, K.; Woo, E.; Jeong, Y. G.; Kim, C.; Huh, J.; Kim, K.-W. Crystalline structures, melting, and crystallization of linear polyethylene in cylindrical nanopores. Macromolecules, 40 (18), 6617-6623, 2007.
[39] Woo, E.; Huh, J.; Jeong, Y. G.; Shin, K. From homogeneous to heterogeneous nucleation of chain molecules under nanoscopic cylindrical confinement. Physical Review Letters, 98 (13), 136103, 2007.
[40] Michell, R. M.; Blaszczyk‐Lezak, I.; Mijangos, C.; Müller, A. J. Confined crystallization of polymers within anodic aluminum oxide templates. Journal of Polymer Science Part B: Polymer Physics, 52 (18), 1179-1194, 2014.
[41] Guan, Y.; Liu, G.; Gao, P.; Li, L.; Ding, G.; Wang, D. Manipulating crystal orientation of poly (ethylene oxide) by nanopores. ACS Macro Letters, 2 (3), 181-184, 2013.
[42] Huang, P.; Zhu, L.; Guo, Y.; Ge, Q.; Jing, A. J.; Chen, W. Y.; Quirk, R. P.; Cheng, S. Z.; Thomas, E. L.; Lotz, B. Confinement size effect on crystal orientation changes of poly (ethylene oxide) blocks in poly (ethylene oxide)-b-polystyrene diblock copolymers. Macromolecules, 37 (10), 3689-3698, 2004.
[43] Schönherr, H.; Frank, C. W. Ultrathin films of poly (ethylene oxides) on oxidized silicon. 1. Spectroscopic characterization of film structure and crystallization kinetics. Macromolecules, 36 (4), 1188-1198, 2003.
[44] Zhang, G.; Lee, P. C.; Jenkins, S.; Dooley, J.; Baer, E. The effect of confined spherulite morphology of high-density polyethylene and polypropylene on their gas barrier properties in multilayered film systems. Polymer, 55 (17), 4521-4530, 2014.
[45] Taden, A.; Landfester, K. Crystallization of poly (ethylene oxide) confined in miniemulsion droplets. Macromolecules, 36 (11), 4037-4041, 2003.
[46] Pan, M.; Yang, L.; Wang, J.; Tang, S.; Zhong, G.; Su, R.; Sen, M. K.; Endoh, M. K.; Koga, T.; Zhu, L. Composite poly (vinylidene fluoride)/polystyrene latex particles for confined crystallization in 180 nm nanospheres via emulsifier-free batch seeded emulsion polymerization. Macromolecules, 47 (8), 2632-2644, 2014.
[47] Montenegro, R.; Landfester, K. Metastable and stable morphologies during crystallization of alkanes in miniemulsion droplets. Langmuir, 19 (15), 5996-6003, 2003.
[48] Frenot, A.; Chronakis, I. S. Polymer nanofibers assembled by electrospinning. Current Opinion in Colloid & Interface Science, 8 (1), 64-75, 2003.
[49] Tekmen, C.; Tsunekawa, Y.; Nakanishi, H. Electrospinning of carbon nanofiber supported Fe/Co/Ni ternary alloy nanoparticles. Journal of Materials Processing Technology, 210 (3), 451-455, 2010.
[50] Reneker, D. H.; Chun, I. Nanometre diameter fibres of polymer, produced by electrospinning. Nanotechnology, 7 (3), 216, 1996.
[51] Chen, D.-R.; Pui, D. Y.; Kaufman, S. L. Electrospraying of conducting liquids for monodisperse aerosol generation in the 4 nm to 1.8 μm diameter range. Journal of Aerosol Science, 26 (6), 963-977, 1995.
[52] Leão, V. N.; Araújo, E. S. Metal Oxide Heteronanostructures Prepared by Electrospinning for the Humidity Detection: Fundamentals and Perspectives. Journal of Materials Science and Chemical Engineering, 7 (07), 43, 2019.
[53] Elahi, M. F.; Lu, W.; Guoping, G.; Khan, F. Core-shell fibers for biomedical applications-a review. Journal of Bioengineering & Biomedical Science, 3 (1), 1-14, 2013.
[54] Zong, X.; Kim, K.; Fang, D.; Ran, S.; Hsiao, B. S.; Chu, B. Structure and process relationship of electrospun bioabsorbable nanofiber membranes. Polymer, 43 (16), 4403-4412, 2002.
[55] Lee, K.; Kim, H.; Bang, H.; Jung, Y.; Lee, S. The change of bead morphology formed on electrospun polystyrene fibers. Polymer, 44 (14), 4029-4034, 2003.
[56] Lee, K. H.; Kim, H. Y.; La, Y. M.; Lee, D. R.; Sung, N. H. Influence of a mixing solvent with tetrahydrofuran and N, N‐dimethylformamide on electrospun poly (vinyl chloride) nonwoven mats. Journal of Polymer Science Part B: Polymer Physics, 40 (19), 2259-2268, 2002.
[57] Deitzel, J. M.; Kleinmeyer, J.; Harris, D.; Tan, N. B. The effect of processing variables on the morphology of electrospun nanofibers and textiles. Polymer, 42 (1), 261-272, 2001.
[58] Ero-Phillips, O.; Jenkins, M.; Stamboulis, A. Tailoring crystallinity of electrospun plla fibres by control of electrospinning parameters. Polymers, 4 (3), 1331-1348, 2012.
[59] Matabola, K.; Moutloali, R. The influence of electrospinning parameters on the morphology and diameter of poly (vinyledene fluoride) nanofibers-effect of sodium chloride. Journal of Materials Science, 48 (16), 5475-5482, 2013.
[60] Buchko, C. J.; Chen, L. C.; Shen, Y.; Martin, D. C. Processing and microstructural characterization of porous biocompatible protein polymer thin films. Polymer, 40 (26), 7397-7407, 1999.
[61] Luo, H.; Huang, Y.; Wang, D.; Shi, J. Coaxial‐electrospinning as a new method to study confined crystallization of polymer. Journal of Polymer Science Part B: Polymer Physics, 51 (5), 376-383, 2013.
[62] Samanta, P.; Thangapandian, V.; Singh, S.; Srivastava, R.; Nandan, B.; Liu, C.-L.; Chen, H.-L. Crystallization behaviour of poly (ethylene oxide) under confinement in the electrospun nanofibers of polystyrene/poly (ethylene oxide) blends. Soft Matter, 12 (23), 5110-5120, 2016.
[63] Zhong, G.; Wang, K.; Zhang, L.; Li, Z.-M.; Fong, H.; Zhu, L. Nanodroplet formation and exclusive homogenously nucleated crystallization in confined electrospun immiscible polymer blend fibers of polystyrene and poly (ethylene oxide). Polymer, 52 (24), 5397-5402, 2011.
[64] Zou, S. F.; Wang, R. Y.; Fan, B.; Xu, J. T.; Fan, Z. Q. Effect of interface and confinement size on the crystallization behavior of plla confined in coaxial electrospun fibers. Journal of Applied Polymer Science, 135 (11), 45980, 2018.
[65] Tsuji, H.; Sumida, K. Poly (l‐lactide): V. effects of storage in swelling solvents on physical properties and structure of poly (l‐lactide). Journal of Applied Polymer Science, 79 (9), 1582-1589, 2001.
[66] Liu, Z.; Li, X.; Yang, Y.; Zhang, K.; Wang, X.; Zhu, M.; Hsiao, B. S. Control of structure and morphology of highly aligned PLLA ultrafine fibers via linear-jet electrospinning. Polymer, 54 (21), 6045-6051, 2013.
[67] Qi, Z.; Yu, H.; Chen, Y.; Zhu, M. Highly porous fibers prepared by electrospinning a ternary system of nonsolvent/solvent/poly (l-lactic acid). Materials Letters, 63 (3-4), 415-418, 2009.
[68] Sato, S.; Gondo, D.; Wada, T.; Kanehashi, S.; Nagai, K. Effects of various liquid organic solvents on solvent‐induced crystallization of amorphous poly (lactic acid) film. Journal of Applied Polymer Science, 129 (3), 1607-1617, 2013.
[69] Maleki, H.; Gharehaghaji, A.; Moroni, L.; Dijkstra, P. J. Influence of the solvent type on the morphology and mechanical properties of electrospun PLLA yarns. Biofabrication, 5 (3), 035014, 2013.
[70] Tsutsumi, S.; Kato, Y.; Namba, K.; Yamamoto, H. Functional composite material design using Hansen solubility parameters. Results in Materials, 4, 100046, 2019.
[71] Mainar, A. M.; Pardo, J.; Royo, F. M.; López, M. C.; Urieta, J. S. Solubility of nonpolar gases in 2, 2, 2-trifluoroethanol at 25° C and 101.33 kPa partial pressure of gas. Journal of Solution Chemistry, 25 (6), 589-595, 1996.
[72] Tan, S.-H.; Inai, R.; Kotaki, M.; Ramakrishna, S. Systematic parameter study for ultra-fine fiber fabrication via electrospinning process. Polymer, 46 (16), 6128-6134, 2005.
[73] Ribeiro, C.; Sencadas, V.; Costa, C. M.; Ribelles, J. L. G.; Lanceros-Méndez, S. Tailoring the morphology and crystallinity of poly (L-lactide acid) electrospun membranes. Science and Technology of Advanced Materials, 12 (1), 015001, 2011.
[74] Nakajima, H.; Takahashi, M.; Kimura, Y. Induced Crystallization of PLLA in the Presence of 1, 3, 5‐Benzenetricarboxylamide Derivatives as Nucleators: Preparation of Haze‐Free Crystalline PLLA Materials. Macromolecular Materials and Engineering, 295 (5), 460-468, 2010.
[75] Pan, P.; Zhu, B.; Kai, W.; Dong, T.; Inoue, Y. Effect of crystallization temperature on crystal modifications and crystallization kinetics of poly (L‐lactide). Journal of Applied Polymer Science, 107 (1), 54-62, 2008.
[76] Sun, Y.-S.; Chung, T.-M.; Li, Y.-J.; Ho, R.-M.; Ko, B.-T.; Jeng, U.-S. Crystal orientation within lamellae-forming block copolymers of semicrystalline poly (4-vinylpyridine)-b-poly (ε-caprolactone). Macromolecules, 40 (18), 6778-6781, 2007.
[77] Theron, S.; Zussman, E.; Yarin, A. Experimental investigation of the governing parameters in the electrospinning of polymer solutions. Polymer, 45 (6), 2017-2030, 2004.
[78] Gazzano, M.; Gualandi, C.; Zucchelli, A.; Sui, T.; Korsunsky, A.; Reinhard, C.; Focarete, M. Structure-morphology correlation in electrospun fibers of semicrystalline polymers by simultaneous synchrotron SAXS-WAXD. Polymer, 63, 154-163, 2015.
[79] Meaurio, E.; Zuza, E.; López-Rodríguez, N.; Sarasua, J. Conformational behavior of poly (L-lactide) studied by infrared spectroscopy. The Journal of Physical Chemistry B, 110 (11), 5790-5800, 2006.
[80] Lotz, B. A. Single Crystals of the Frustrated β-Phase and Genesis of the Disordered α′-Phase of Poly (l-lactic acid). ACS Macro Letters, 4 (5), 602-605, 2015.
[81] Kuo, C.-Y.; Lin, H.-N.; Tsai, H.-A.; Wang, D.-M.; Lai, J.-Y. Fabrication of a high hydrophobic PVDF membrane via nonsolvent induced phase separation. Desalination, 233 (1-3), 40-47, 2008.
[82] Xin, Y.; Fujimoto, T.; Uyama, H. Facile fabrication of polycarbonate monolith by non-solvent induced phase separation method. Polymer, 53 (14), 2847-2853, 2012.
[83] Iesavand, H.; Rahmati, M.; Afzali, D.; Modiri, S. Investigation on absorption and release of mercaptopurine anticancer drug from modified polylactic acid as polymer carrier by molecular dynamic simulation. Materials Science and Engineering: C, 105, 110010, 2019.
[84] Zhang, H.; Bai, H.; Liu, Z.; Zhang, Q.; Fu, Q. Toward high-performance poly (L-lactide) fibers via tailoring crystallization with the aid of fibrillar nucleating agent. ACS Sustainable Chemistry & Engineering, 4 (7), 3939-3947, 2016.
[85] Yu, Q.-h.; Zhu, F.; Su, J.-j.; Han, J. Effective stress transferring interface and mechanical property enhancement of poly (L-lactide)/multi-walled carbon nanotubes fibers. Materials Chemistry and Physics, 234, 296-303, 2019.
[86] Moradkhannejhad, L.; Abdouss, M.; Nikfarjam, N.; Shahriari, M. H.; Heidary, V. The effect of molecular weight and content of PEG on in vitro drug release of electrospun curcumin loaded PLA/PEG nanofibers. Journal of Drug Delivery Science and Technology, 56, 101554, 2020.
[87] Zhu, P.-w.; Tung, J.; Phillips, A.; Edward, G. Morphological development of oriented isotactic polypropylene in the presence of a nucleating agent. Macromolecules, 39 (5), 1821-1831, 2006.
[88] Shi, N.; Dou, Q. Non-isothermal cold crystallization kinetics of poly (lactic acid)/poly (butylene adipate-co-terephthalate)/treated calcium carbonate composites. Journal of Thermal Analysis and Calorimetry, 119 (1), 635-642, 2015.
[89] Supaphol, P.; Dangseeyun, N.; Srimoaon, P. Non-isothermal melt crystallization kinetics for poly (trimethylene terephthalate)/poly (butylene terephthalate) blends. Polymer testing, 23 (2), 175-185, 2004.
[90] Ravari, F.; Mashak, A.; Nekoomanesh, M.; Mobedi, H. Non-isothermal cold crystallization behavior and kinetics of poly (l-lactide): effect of l-lactide dimer. Polymer bulletin, 70 (9), 2569-2586, 2013.
[91] Wu, D.; Wu, L.; Wu, L.; Xu, B.; Zhang, Y.; Zhang, M. Nonisothermal cold crystallization behavior and kinetics of polylactide/clay nanocomposites. Journal of Polymer Science Part B: Polymer Physics, 45 (9), 1100-1113, 2007.
[92] Zhao, Y.; Qiu, Z.; Yan, S.; Yang, W. Crystallization behavior of biodegradable poly (L‐lactide)/multiwalled carbon nanotubes nanocomposites from the amorphous state. Polymer Engineering & Science, 51 (8), 1564-1573, 2011.
[93] Mieczkowski, R. Solubility parameter components of some polyols. European Polymer Journal, 27 (4-5), 377-379, 1991.
[94] Zhang, H.; Wang, S.; Zhang, S.; Ma, R.; Wang, Y.; Cao, W.; Liu, C.; Shen, C. Crystallization behavior of poly (lactic acid) with a self-assembly aryl amide nucleating agent probed by real-time infrared spectroscopy and X-ray diffraction. Polymer Testing, 64, 12-19, 2017.
[95] Kushwaha, N.; Kaushik, D. Recent advances and future prospects of phthalimide derivatives. Journal of Applied Pharmaceutical Science, 6 (03), 159-171, 2016.
[96] Liang, R.; Chen, Y.-c.; Zhang, C.-q.; Yin, J.; Liu, X.-l.; Wang, L.-k.; Kong, R.; Feng, X.; Yang, J.-j. Crystallization behavior of biodegradable poly (ethylene adipate) modulated by a benign nucleating agent: Zinc phenylphosphonate. Chinese Journal of Polymer Science, 35 (4), 558-568, 2017.
[97] Li, D.; Guo, G.; Deng, X.; Fan, R.; Guo, Q.; Fan, M.; Liang, J.; Luo, F.; Qian, Z. PLA/PEG-PPG-PEG/Dexamethasone implant prepared by hot-melt extrusion for controlled release of immunosuppressive drug to implantable medical devices, part 2: in vivo evaluation. Drug Delivery, 20 (3-4), 134-142, 2013.
[98] Langer, R.; Peppas, N. A. Present and future applications of biomaterials in controlled drug delivery systems. Biomaterials, 2 (4), 201-214, 1981.
[99] Tham, C.; Hamid, Z. A. A.; Ahmad, Z.; Ismail, H., Surface engineered poly (lactic acid)(PLA) microspheres by chemical treatment for drug delivery system. Trans Tech Publications: 2014; Vol. 594.