Sheibani Nasser
Faculty of Chemistry and Chemical Engineering, Malek-Ashtar University of Technology, Tehran, Iran.
J Mol Model. 2022 Nov 30;28(12):405. doi: 10.1007/s00894-022-05399-y.
Since solid composite propellants are composed of a high percentage of oxidizers, the search for green oxidizers such as ammonium dinitramide (ADN) as a substitute for non-eco-friendly ammonium perchlorate (AP) is an important issue. ADN/GAP propellants are good green candidates to replace conventional AP/HTPB propellants. The incompatibility issue of ADN with isocyanate curing agents of polyurethane binders is a well-known problem.
In this research, from the perspective of molecular dynamics and solubility parameter concept, an attempt was made to study molecular factors determining the preferable curing system for ADN/GAP composite propellants by examining the interaction energy between different isocyanate curing agents and ADN as well as GAP. From another standpoint, the aim is to show that the reactivity rate of different isocyanates with ADN has a significant difference, which has been investigated using molecular dynamics simulation and experimentally. The examined isocyanates include N100, IPDI, TDI, DDI, IPDI/N100, and DDI/N100. The activity of the selected curing system upon ADN was investigated using infrared spectroscopy at different time intervals and compared with the N100 as a conventional curing system. The results show that a meaningful improvement occurs using the selected curing system.
由于固体复合推进剂由高比例的氧化剂组成，寻找绿色氧化剂如二硝酰胺铵（ADN）来替代不环保的高氯酸铵（AP）是一个重要问题。ADN/GAP推进剂是替代传统AP/HTPB推进剂的良好绿色候选物。ADN与聚氨酯粘合剂的异氰酸酯固化剂之间的不相容问题是一个众所周知的问题。
在本研究中，从分子动力学和溶解度参数概念的角度出发，通过研究不同异氰酸酯固化剂与ADN以及GAP之间的相互作用能，试图研究决定ADN/GAP复合推进剂优选固化体系的分子因素。从另一个角度来看，目的是表明不同异氰酸酯与ADN的反应速率存在显著差异，这已通过分子动力学模拟和实验进行了研究。所研究的异氰酸酯包括N100、异佛尔酮二异氰酸酯（IPDI）、甲苯二异氰酸酯（TDI）、4,4'-二苯基甲烷二异氰酸酯（DDI）、IPDI/N100和DDI/N100。使用红外光谱在不同时间间隔研究所选固化体系对ADN的活性，并与作为传统固化体系的N100进行比较。结果表明，使用所选固化体系有显著改善。
