环氧磷腈固化的等温动力学

Isothermal Kinetics of Epoxyphosphazene Cure.

作者信息

Bornosuz Natalia V, Gorbunova Irina Yu, Petrakova Viktoria V, Shutov Vyacheslav V, Kireev Vyacheslav V, Onuchin Denis V, Sirotin Igor S

机构信息

Faculty of Petrochemistry and Polymer Materials, Mendeleev University of Chemical Technology of Russia, Miusskaya sq. 9, 125047 Moscow, Russia.

出版信息

Polymers (Basel). 2021 Jan 18;13(2):297. doi: 10.3390/polym13020297.

DOI:10.3390/polym13020297

PMID:33477707

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7831929/

Abstract

The influence of epoxycyclophosphazene modifier on the process of epoxy-amine curing was studied by differential scanning calorimetry (DSC). The study revealed that the curing process of epoxyphosphazene binders with 4'4'diaminodiphenylsulfone (DDS) provides more complete curing of the formulations in comparison with ones applying low molecular-weight polyamide curing agent (L-20). The isothermal kinetics of curing was described by means of model fitting and the isoconversional approach (Friedman method). Accurate n-order approximation was obtained for all systems under study. In particular, the 2-order equation fits well with the main part of curing excluding high degrees of conversion. The process of curing could be distinguished into three zones. The transition from zone 2 to zone 3 correlates with gelation. According to the isoconversional analysis by Friedman method, the diffusion-controlled mechanism is found at final stage of curing.

摘要

采用差示扫描量热法（DSC）研究了环氧环磷腈改性剂对环氧-胺固化过程的影响。研究表明，与使用低分子量聚酰胺固化剂（L-20）的配方相比，含4,4'-二氨基二苯砜（DDS）的环氧磷腈粘合剂的固化过程能使配方实现更完全的固化。通过模型拟合和等转化率方法（弗里德曼方法）描述了固化的等温动力学。对所有研究体系都获得了精确的n级近似。特别是，二级方程与固化的主要部分拟合良好，但不包括高转化率阶段。固化过程可分为三个区域。从区域2到区域3的转变与凝胶化相关。根据弗里德曼方法的等转化率分析，在固化的最后阶段发现了扩散控制机制。