Migration kinetics and mechanisms of plasticizers, stabilizers at interfaces of NEPE propellant/HTPB liner/EDPM insulation

• Published in: Journal of hazardous materials 2012-08, Vol.229-230, p.251-257
• Main Authors: Huang, Zhi-ping, Nie, Hai-ying, Zhang, Yuan-yuan, Tan, Li-min, Yin, Hua-li, Ma, Xin-gang
• Format: Article
• Language: English
• Subjects: activation energy; aniline; Aniline Compounds - analysis; Applied sciences; Butadienes - chemistry; Butanols - analysis; diffusivity; EDPM insulation; Elastomers - chemistry; energy; Ethers - chemistry; ethylene; Ethylenes - chemistry; Exact sciences and technology; high performance liquid chromatography; HTPB liner; hydrogen bonding; insulating materials; Kinetics; Migration; NEPE propellant; nitrates; Nitroglycerin - analysis; Plasticizer; plasticizers; Plasticizers - analysis; Pollution; propylene; solvents; Stabilizer; stabilizers; temperature
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2012.05.103

[Display omitted] ► Migration appeared in the interfaces of NEPE propellant/HTPB liner/EPDM insulation was studied. ► The migration occurred within 1mm to the interfaces. ► The apparent migration activation energy (Ea) of mobile components is among 15 and 50kJ/mol. ► The average diffusion coefficients were in the range of 10−19m2s−1 to 10−16m2s−1. ► The migration kinetics is affected by the property of a mobile component and the based material. Migration appeared in the interfaces of nitrate ester plasticized polyether (NEPE) based propellant/hydroxyl-terminated polybutadiene (HTPB) based liner/ethylene propylene terpolymer (EPDM) based insulation was studied by aging at different temperatures. The migration components were extracted with solvent and determined by high performance liquid chromatography (HPLC). The migration occurred within 1mm to the interfaces, and the apparent migration activation energy (Ea) of nitroglycerin (NG), 1,2,4-butanetriol trinitrate (BTTN) and a kind of aniline stabilizer AD in propellant, liner and insulation was calculated respectively on the basis of HPLC data. The Ea values were among 15 and 50kJ/mol, which were much less than chemical energy, and almost the same as hydrogen bond energy. The average diffusion coefficients were in the range of 10−19m2s−1 to 10−16m2s−1. It seemed the faster the migration rates, the smaller the apparent migration activation energy, the larger the diffusion coefficient and the less the amount of migration. It could be explained that the migration rate and energy were affected by the molecular volume of a mobile component and its diffusion property, and the amount of migration was resulted from the molecular polarity comparability of a mobile component to the based material.