Abstract
To further verify the mechanism of forming multi-core structure during the direct melt copolycondensation of lactic acid (LA) with compounds containing multi-hydroxyl groups, the biodegradable material poly(lactic acid-co-sorbitol) [P(LA-co-SB)] was synthesized by using D,L-lactic acid (D,L-LA) and sorbitol (SB) as starting materials. For the molar feed ratio n(LA)/n(SB) of 120/1, optimal synthetic conditions were investigated. After prepolymerization at 140 °C for 8 h, melt copolymerization with the catalysis of SnO (0.5 wt %) at 160 °C for 6 h gave a polymer with the biggest intrinsic viscosity ([η]) 0.91 dL•g−1. The copolymer P(LA-co-SB)s obtained at different molar feed ratios were characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results show that the weight-average molecular weight (Mw) doesn’t increase all the time along with the increasing of the molar feed ratio n(LA)/n(SB), but a Mw peak value exists, which validates again the special Mw peak phenomenon during the direct melt copolycondensation of LA with the monomers containing multifunctional groups (including polyols, e.g. glycerol). However, compared with the results of using glycerol as the core, the mechanism of forming the multi-core copolymer is somewhat different due to SB’s different structure. All the results show that the Mw peak value of the copolymers with multi-core structure is related to not only the number of hydroxyl groups in polyols, but also the reactivity of hydroxyl groups resulted from their type, and the steric hindrance of hydroxyl groups in the polyol.
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References
Fukuoka A, Dhepe PL (2006) Angew Chem Int Ed 45:5161
Corma A, Iborra S, Velty A (2007) Chem Rev 107:2411
Rinaldi R, Schüth F (2009) Energy Environ Sci 2:610
Radhika GS, Moorthy SN (2009) Trends Carbohydr Res 1:71
Arvanitoyannis I, Nakayama A, Psomiadou E, Kawasaki N, Yamamoto N (1996) Polymer 37:651
Hao QH, Li F, Li QB, Li Y, Jia L, Yang J, Fang Q, Cao A (2005) Biomacromol 6:2236
Maharana T, Mohanty B, Negi YS (2009) Prog Polym Sci 34:99
Konishi S, Yokoi T, Ochiai B, Endo T (2010) Polym Bull 64:435
Sedlarik V, Kucharczyk P, Kasparkova V, Drbohlav J, Salakova A, Saha P (2010) J Appl Polym Sci 116:1597
Kucharczyk P, Poljansek I, Sedlarik V, Kasparkova V, Salakova A, Drbohlav J, Cvelbar U, Saha P (2011) J Appl Polym Sci 122:1275
Cadar O, Paul M, Roman C, Miclean M, Majdik C (2012) Polym Degrad Stab 97:354
Lin YL, Zhang AQ, Wang LS (2012) J Appl Polym Sci 124:4496
Harrane A, Belaouedj MA, Meghabar R, Belbachir M (2012) J Polym Res 19:1
Xu B, Dou HJ, Tao K, Sun K, Lu R, Shi WB (2011) J Polym Res 18:131
Wang ZY, Zhao HJ, Wang QF, Ye RR, David EF (2010) J Appl Polym Sci 117:1405
Wang ZY, Luo YF, Ye RR, Song XM (2011) J Polym Res 18:499
Luo SH, Wang ZY, Mao CX, Huo JP (2011) J Polym Res 18:2093
Arvanitoyannis L, Nakayama A, Kawasaki N, Yamamoto N (1995) Polymer 36:2947
Zhang WA, Zheng SX (2007) Polym Bull 58:767
Gou PF, Zhu WP, Shen ZQ (2008) J Polym Sci Part A Polym Chem 46:2108
Luo YF, Wang ZY, Ye RR, Luo SH, Yang LT (2011) J Appl Polym Sci 119:1883
Ye RR, Wang ZY, Wang QF, Yang K, Luo SH (2011) J Appl Polym Sci 121:3662
Wang ZY, Zhao YM, Wang F, Wang J (2006) J Appl Polym Sci 99:244
Ye RR, Wang ZY, Yang K, Luo SH (2010) Des Monomers Polym 13:415
Zhao YM, Wang ZY, Yang F (2005) J Appl Polym Sci 97:195
Moon SI, Lee CW, Miyamoto M, Kimura Y (2000) J Polym Sci Part A Polym Chem 38:1673
Moon SI, Lee CW, Taniguchi I, Miyamoto M, Kimura Y (2001) Polymer 42:5059
Moon SI, Kimura Y (2003) Polym Int 52:299
Duan JF, Du J, Zheng YB (2007) J Appl Polym Sci 103:3585
Yilmaz M, Egri S, Yildiz N, Calimli A, Piskin E (2011) J Polym Res 18:975
Zhou SB, Deng XM, Li XH (2004) J Appl Polym Sci 91:1848
Yang F, Song FL, Pan YF, Wang ZY, Yang YQ, Zhao YM, Liang SZ, Zhang YM (2010) J Microencapsul 27:133
Wang N, Wu XS, Lujan-Upton H, Donahue E, Siddiqui A (1997) J Biomater Sci Polym Ed 8:905
Wang N, Wu XS (1998) J Biomater Sci Polym Ed 9:75
Inoue K, Yamashiro M, Iji M (2009) J Appl Polym Sci 112:876
Grijpma DW, Melchels FPW, Hou Q, Jan F (2006) Mater Res Innov 10:321
Kim ES, Kim BC, Kim SH (2004) J Polym Sci Part B Polym Phys 42:939
Luo YF, Wang ZY, Song XM, Mao ZZ, Zhao HJ (2008) Chin J Synth Chem 16:166
Luo SH, Wang ZY, Huang DN, Mao CX, Xiong JF (2011) Adv Mater Res 80–81:370
Luo YF, Wang ZY, Mao ZZ, Song XM (2008) Chin Fine Chem 25:13
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We are grateful to the financial support by Guangdong Provincial Natural Science Foundation of China (No. 5300082), the 3rd Talents Special Funds of Guangdong Higher Education (grant number Guangdong-Finance-Education[2011]431), and National Natural Science Foundation of China (No. 20772035).
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Luo, SH., Wang, QF., Xiong, JF. et al. Synthesis of biodegradable material poly(lactic acid-co-sorbitol) via direct melt polycondensation and its reaction mechanism. J Polym Res 19, 9962 (2012). https://doi.org/10.1007/s10965-012-9962-x
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DOI: https://doi.org/10.1007/s10965-012-9962-x