Jalal Mahir A, Abood Einas A, Sweah Zainab J, Al-Lami Hadi S, Abdulkarem Alyaa Abdulhasan, Abdulelah Haider
Department of Polymer Technology, Polymer Research Center, University of Basrah, Basrah 61004, Iraq.
Department of Fuel and Energy Technologies Engineering, Shatt Al-Arab University, Basrah 61004, Iraq.
Polymers (Basel). 2025 Mar 4;17(5):684. doi: 10.3390/polym17050684.
In this study, modification of poly(adipic anhydride) through branching its chains was carried out via melt condensation polymerization with D-mannitol. The percentage of mannitol was varied (3, 4, 5, 10, 15, and 20 Wt.%) and the resulting copolymers were purified and characterized by FT-IR and C-NMR. These analyses indicated that linear chains of poly(adipic anhydride) can react with strong nucleophiles and dissociate to produce highly branched poly(adipic anhydride--mannitol adipate) which confirms the validity of the proposed mechanism. The copolymer's molecular weight characteristics have been also examined using GPC analysis. Thermal properties of copolymers were also investigated using TGA, DTG, and DCS analyses. TGA/DTG revealed that the thermal degradation of copolymers proceeds in multi-stage decomposition, whereas the shift and pattern change of the melting point peak of DSC curves can identify the weight percentage of mannitol for homogenous copolymers. Two non-isothermal models, the Flynn-Wall-Ozawa and Kissinger methods, have been also employed to analyze thermogravimetric data collected from the thermal decomposition of the copolymers and found that Flynn-Wall-Ozawa method provides better results with R correlation up to 99.3%. The activation energy in the region of was determined and found that an increase in mannitol contents in copolymer has a positive impact on its thermal stability.
在本研究中，通过与D - 甘露醇进行熔融缩聚反应，对聚（己二酸酐）的链进行支化改性。甘露醇的百分比有所变化（3、4、5、10、15和20重量%），所得共聚物经过纯化，并通过傅里叶变换红外光谱（FT - IR）和碳核磁共振（C - NMR）进行表征。这些分析表明，聚（己二酸酐）的线性链可与强亲核试剂反应并解离，生成高度支化的聚（己二酸酐 - 甘露醇己二酸酯），这证实了所提出机制的有效性。还使用凝胶渗透色谱（GPC）分析检查了共聚物的分子量特性。还使用热重分析（TGA）、微商热重分析（DTG）和差示扫描量热法（DCS）分析研究了共聚物的热性能。TGA/DTG表明，共聚物的热降解以多阶段分解进行，而DSC曲线熔点峰的位移和模式变化可确定均相共聚物中甘露醇的重量百分比。还采用了两种非等温模型，即弗林 - 沃尔 - 小泽（Flynn - Wall - Ozawa）法和基辛格（Kissinger）法，来分析从共聚物热分解收集的热重数据，发现弗林 - 沃尔 - 小泽法提供了更好的结果，相关系数R高达99.3%。测定了该区域的活化能，发现共聚物中甘露醇含量的增加对其热稳定性有积极影响。
