塑料科技2026，Vol.54Issue(3)：136-142,7.DOI:10.15925/j.cnki.issn1005-3360.2026.03.025
端基间多重氢键对聚乳酸结晶行为的影响及响应
Effect and Response of Inter-end-group Multiple Hydrogen Bonding on Crystallization Behavior of Polylactide
摘要
Abstract
To clarify the effect of terminal hydrogen bonding on the crystallization behavior and dynamic response mechanism of polymers,single-ended 2-ureido-4[1H]-pyrimidinone(UPy)functionalized polylactide(UPLLA)with different molecular weights(5,9,12 kg/mol)were synthesized and investigated.¹H NMR and Fourier transform infrared spectroscopy(FTIR)confirmed the successful incorporation of UPy groups onto the PLA chain ends.Differential scanning calorimetry analysis revealed that terminal hydrogen bonding significantly suppressed the melt crystallization ability of PLA,resulting in elevated cold crystallization temperatures(increasing from 84.7℃to 99.6℃for the 5k sample),reduced cold crystallization enthalpies(decreasing from 43.1 J/g to 15.4 J/g for the 5k sample)and melting enthalpies(decreasing from 30.6 J/g to 8.1 J/g for the 5k sample),and depressed melting temperatures(a decrease of 17.9℃for the 5k sample).The suppressive effect weakened with increasing molecular weight,primarily attributed to the attenuation of the dragging effect of terminal groups on molecular chain motion as chain length increased.In situ variable-temperature FTIR studies further elucidated the dynamic response mechanism of terminal hydrogen bonding.During the recrystallization-melting process,the enhanced molecular chain mobility released upon melting of the α'-crystals drove the reorganization of terminal hydrogen bonds,leading to an anomalous increase in hydrogen bonding strength within the 100～130℃temperature range for the 9k and 12k samples,thereby confirming that terminal hydrogen bonds could respond to polymer phase transitions.关键词
聚乳酸/端基/氢键/结晶行为Key words
PLA/Terminal groups/Hydrogen bonds/Crystallization behavior分类
化学化工引用本文复制引用
陈聪,魏雪巍,叶海木..端基间多重氢键对聚乳酸结晶行为的影响及响应[J].塑料科技,2026,54(3):136-142,7.基金项目
国家自然科学基金项目(22173116) （22173116）
中国石油大学(北京)科研基金项目(2462025YJRC032) （北京）
