Matykiewicz Danuta, Dudziec Beata
Faculty of Mechanical Engineering, Poznan University of Technology, Piotrowo 3, Poznan 61-138, Poland.
Faculty of Chemistry and Center for Advanced Technologies, Adam Mickiewicz University in Poznan, Uniwersytetu Poznanskiego 10, Poznan 61-614, Poland.
ACS Omega. 2025 Jan 27;10(5):4353-4366. doi: 10.1021/acsomega.4c06532. eCollection 2025 Feb 11.
Decreasing fossil fuel resources results in a growing demand for polymeric materials obtained from renewable raw materials, such as eugenol. Therefore, this work aimed to assess the kinetics of cross-linking and degradation of epoxy resin obtained from eugenol derivatives and cured with three types of amines: aliphatic: triethylenetetramine (TETA); aromatic: diaminodiphenylmethane (DDM), and cycloaliphatic isophorone diamine (IDA). The product was characterized by H, C, and P NMR as well as ESI MS techniques. The curing kinetics of the biobased resin was studied using differential scanning calorimetry (DSC) at different heating rates. Fourier transform infrared (FTIR) spectroscopy was used to assess chemical changes in bioepoxy monomer after the curing process. The DSC method confirmed the occurrence of an exothermic curing reaction of the tested bioresin for all tested curing agents. The peak temperature and enthalpy Δ values determined during DSC analysis depended on the type of curing agent. The highest values of (142.6-161.4 °C) and Δ (28.5-38.3 J/g) were recorded for the TEEP + DDM composition. For the remaining compositions, the values were lower and were as follows: for TEEP + TETA, = 115.0 to 129.9 °C and Δ = 12.4-26.5 J/g and for TEEP + IDA, = 118.0-137.1 °C and Δ = 16.3 to 35.5 J/g. According to the Kissinger and Ozawa model, the activation energy of the resin cross-linking process was determined. The calculated activation energies according to Kissinger and Ozawa were 65.38 and 55.90 kJ/mol for TEEP + TETA, 60.09 and 63.84 kJ/mol for TEEP + DDM, and 57.36 and 60.85 kJ/mol for TEEP+IDA, respectively. The kinetics of thermal degradation of the eugenol-based resin were studied by thermogravimetric analysis (TGA) in a nitrogen atmosphere. Moreover, it should be emphasized that compared to commercial resins, bioresin has a much lower maximum degradation rate determined by DTG and a higher amount of char residue after thermal degradation, both in nitrogen and in air.
化石燃料资源的减少导致对源自可再生原料（如丁香酚）的聚合物材料的需求不断增长。因此，本工作旨在评估由丁香酚衍生物制得并用三种类型的胺固化的环氧树脂的交联和降解动力学：脂肪族：三亚乙基四胺（TETA）；芳香族：二氨基二苯甲烷（DDM），以及脂环族异佛尔酮二胺（IDA）。通过H、C和P核磁共振以及电喷雾质谱技术对产物进行了表征。使用差示扫描量热法（DSC）在不同加热速率下研究了生物基树脂的固化动力学。傅里叶变换红外（FTIR）光谱用于评估固化过程后生物环氧树脂单体的化学变化。DSC方法证实了对于所有测试的固化剂，所测试的生物树脂均发生放热固化反应。DSC分析过程中测定的峰值温度和焓变Δ值取决于固化剂的类型。TEEP + DDM组合物的峰值温度最高（142.6 - 161.4℃），焓变Δ值也最高（28.5 - 38.3 J/g）。对于其余组合物，这些值较低，具体如下：对于TEEP + TETA，峰值温度为115.0至129.9℃，焓变Δ为12.4 - 26.5 J/g；对于TEEP + IDA，峰值温度为118.0 - 137.1℃，焓变Δ为16.3至35.5 J/g。根据基辛格和小泽模型，确定了树脂交联过程的活化能。根据基辛格和小泽模型计算的活化能，对于TEEP + TETA分别为65.38和55.90 kJ/mol，对于TEEP + DDM分别为60.09和63.84 kJ/mol，对于TEEP + IDA分别为57.36和60.85 kJ/mol。通过在氮气气氛中的热重分析（TGA）研究了丁香酚基树脂的热降解动力学。此外，应该强调的是，与商业树脂相比，生物树脂由DTG测定的最大降解速率要低得多，并且在氮气和空气中热降解后的残炭量更高。
