The energetic plasticizer glycidyl azide polymer (GAP) is used for new types of rocket propellants which are formulated with the objective of achieving higher burning rates. The reaction profiles for several possible initial steps in the decomposition of mixtures of the nitramines octahydro-1,3,5,7-tetranitro-1,3,5,7- tetrazacyclooctane (HMX), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and hexanitrohexaazaisowurtzitane (CL20) with a monomer of GAP-diol have been examined computationally. Comparison of the activation energies for the decomposition of the mixtures with those for the decomposition of the isolated nitramines shows that the presence of GAP-diol decreases the activation energy for the elimination of NO2 by at least to 8 kJ mol-1 for CL20, wheras the NO2 elimination from HMX is only favored by 1 kJ mol-1 and NO2 elimination from RDX is inhibited in the presence of GAP-diol by 2 kJ mol-1.
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
The energetic plasticizer glycidyl azide polymer (GAP) is used for new types of rocket propellants which are formulated with the objective of achieving higher burning rates. While the homolytic fission of an N-NO2 bond, which we discussed previously, is energetically favored as the initial decomposition step, experiments show that the decomposition of mixtures of the nitramines octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and hexanitrohexaazaisowurtzitane (CL20) with a monomer of GAP-diol is more complex. Therefore we investigated further possible decomposition pathways. Comparison of the calculated activation energies for the decomposition of the mixtures with those for the decomposition of the isolated nitramines shows that the presence of GAP-dioldecreases the activation energies of certain decomposition steps by up to 20 kJ mol-1. GAP-diol facilitates the decomposition of CL20 and RDX to a larger extent than the decomposition of HMX. However, the investigated decomposition pathways of GAP-diolwere inhibited by the presence of the nitramines.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.