Lascano Diego, Lerma-Canto Alejandro, Fombuena Vicent, Balart Rafael, Montanes Nestor, Quiles-Carrillo Luis
Technological Institute of Materials (ITM), Universitat Politècnica de València (UPV), Plaza Ferrándiz y Carbonell 1, 03801 Alcoy, Spain.
Escuela Politécnica Nacional, Quito 17-01-2759, Ecuador.
Polymers (Basel). 2021 Apr 14;13(8):1279. doi: 10.3390/polym13081279.
The curing process of epoxy resin based on epoxidized linseed oil (ELO) is studied using dynamic differential scanning calorimetry (DSC) in order to determine the kinetic triplet (, f(α) and ) at different heating rates. The apparent activation energy, , has been calculated by several differential and integral isoconversional methods, namely Kissinger, Friedman, Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Starink. All methods provide similar values of (between 66 and 69 kJ/mol), and this shows independence versus the heating rate used. The epoxy resins crosslinking is characterized by a multi-step process. However, for the sake of the simplicity and to facilitate the understanding of the influence of the oxirane location on the curing kinetic, this can be assimilated to a single-step process. The reaction model has a high proportion of autocatalytic process, fulfilling that is between 0 and and < αp∞. Using as reference the model proposed by Šesták-Berggren, by obtaining two parameters ( and ) it is possible to obtain, on the one hand, the kinetic parameters and, on the other hand, a graphical comparison of the degree of conversion, , versus temperature () at different heating rates with the average and values of this model. The good accuracy of the proposed model with regard to the actual values obtained by DSC gives consistency to the obtained parameters, thus suggesting the crosslinking of the ELO-based epoxy has apparent activation energies similar to other petroleum-derived epoxy resins.
采用动态差示扫描量热法（DSC）研究了基于环氧化亚麻籽油（ELO）的环氧树脂的固化过程，以确定不同升温速率下的动力学三元组（(E_a)、(f(α))和(g(α))）。通过几种微分和积分等转化率方法，即基辛格法、弗里德曼法、弗林-沃尔-小泽法（FWO）、基辛格-赤平-ose法（KAS）和斯塔林克法，计算了表观活化能(E_a)。所有方法得到的(E_a)值相近（在66至69kJ/mol之间），这表明其与所用升温速率无关。环氧树脂的交联具有多步过程。然而，为了简化并便于理解环氧乙烷位置对固化动力学的影响，可将其简化为单步过程。该反应模型具有较高比例的自催化过程，满足(0\lt n\lt1)且(α_p∞\lt1)。以Šesták-Berggren提出的模型为参考，通过获得两个参数（(n)和(α_p∞)），一方面可以得到动力学参数，另一方面可以在不同升温速率下，将转化率(α)与温度（(T)）进行图形比较，并给出该模型的平均(n)和(α_p∞)值。所提出的模型与DSC实际测得值具有良好的准确性，这使得所获得的参数具有一致性，从而表明基于ELO的环氧树脂交联的表观活化能与其他石油衍生环氧树脂相似。
