Synthesis And Application Of The Propellants Based On The Energetic Plasticizer Glycidyl Azide Polymer (GAP)

The composite rocket propellants has been widely used because of its excellent energy characteristics. However the propellants based on the energetic plasticizer glycidyl azide polymer (GAP) contains a lot of plasticizer and solid nitramine filler particles, leading to poor mechanical properties of this propellant which is a difficult problem that hinders its development. According to the formula characteristics of the composite polyether propellant, combining the characteristics of boric acid ester, ethyleneimine and amines bonding agents, special bonding agent for the GAP propellant was designed, besides the synthesis methods and structure-property relationship were deeply studied and the efficient bonding agent of GAP propellant was eventually developed which solved the problem of poor mechanical property of GAP propellant. The results will be able to promote the research work of the composite rocket propellants.According to the characteristics of the GAP composite propellant, The technical route was determined using neutral polymer bonding agent (NPBA). The boric acid ester, ethyleneimine and amines were connected in the macromolecular chain to improve the bonding effect of bonding agent in order to get more efficient key bonding agent sample.First of all, experiments using Series of NPBA sample varying from molecular weight, hydroxyl value and solubility parameter with precision synthesis method has been done and the parameters which effect NPBA have been analyzed. The result showed that the NPBA whose molecular weight is around 3000, hydroxyl value around 2.0mmol/g, solubility parameter around 25.42(J/cm3)1/2 has the best interfacial bongding effect.Secondly, With boric acid,1,2- propylene glycol and 2-hydroxyethyl acrylate as the main raw materials, the intermediate of cyclic borate ester was synthesized by the method of transesterification. Product structures were characterized by using FTIR, 1HNMR; intermediate of ethyleneimine was synthesized used MAPO and acrylic acid as main raw materials; 2-diethylaminoethyl methacrylate was choosen as intermediate of amines.Finally, functional monomer were connected in macromolecular chain used the synthesis method and structural parameters which determined in the first step to get new NPBA. Then compared them with the traditional NPBA which has the best effect on the bonding effect, the result showed that the bonding effect of the new NPBA with more functional groups is improved due to the synergistic action of the multiple groups. After the addition of NNPBA-5, the tensile strength of the column at 20? was 1.39Mpa, and the elongation at break was 72.7%, with increased by 27.5% and 25.6% compared with NPBA-2.