Four different GAP mixtures with di‐ and tri‐functional GAP types were successfully cured with bis‐propargyl‐succinate (BPS) via 1,3 dipolar cycloaddition reaction between the azido groups of GAP and the triple bonds of the propargyl ester. Investigation of one series of curing on di‐functional and another series on tri‐functional GAP was done and compared with two additional curing series on mixtures of di‐ and tri‐functional GAP. The BPS which acted as a curing agent analog to isocyanate in classical polyurethane systems, was varied in its content, and the influence on the mechanical properties of the cross‐linked binders was measured by tensile tests. The mechanical properties could be adjusted in a wide range by varying the amount of BPS. The E modulus of the tested samples was in the range of 0.06–0.674 N mm−2 at elongations between 50 and 95% and the maximum stress was in the range of 0.05–0.32 N mm−2. Increasing contents of BPS showed, in thermal analysis by DSC, only a small decrease in the decomposition energy and slightly raised glass transition temperatures. The required amount of inert curing agent for complete cure of GAP is lower for BPS in comparison to isocyanate, so this will result in a higher total energy content in the binder system. However, BPS‐cured systems can lead to higher glass transition temperatures than isocyanate‐based binder systems. The curing process has been monitored by measuring the increasing viscosity at 50 and 60 °C. The curing time of the investigated binder systems for quantitative curing at 65 °C is around four days, which was checked by measuring the surface hardness, but at room temperature the premixed curing samples staid liquid for around 1 week.

In this contribution two ways are described, how it is possible to achieve perfectly cured and processible propellants with prilled ADN, low amounts of HMX 5 μm mps and a binder system based on GAP diole and GAP triole oligomers with and without TMETN as a nitrate ester plasticizer. It was shown how it will be possible to suppress the strongly gas forming reaction between ADN and reactive isocyanates by a mixture of stabilizers. In this way it was possible to create minimum smoke ADN/HMX/GAP/TMETN propellants cured with the triisocyanate N100. In the second part an unconventional binder system based on the 1.3 dipolar cycloaddition reaction of azido groups with acetylene compounds forming 1,2,3‐triazole heterocyclic rings has been applied for ADN/GAP and AP/GAP propellants. Together with small parts of HMX formulations with ADN/HMX/GAP and the corresponding AP/HMX/GAP exhibit high thermodynamic performance, are easily processible, and cure successfully at 60 °C. Their basic properties consisting of burning behavior and mechanical properties, at ambient temperature, chemical stability, and sensitivity have been investigated and are compared to each other.

Glycidyl azide-r-(3,3-bis(azidomethyl)oxetane) copolymers were synthesized by cationic copolymerization of epichlorohydrin and 3,3-bis(bromomethyl)oxetane, using butane-1,4-diol as initiator and boron trifluoride etherate as catalyst, followed by azidation of the halogenated copolymer. The main objective of this work is the preparation of an amorphous polymer with energetic content higher than that of the well known glycidyl azide homopolymer. The effect of experimental conditions, like i.e. the rate of monomer feeding, on the final molecular weight and functionality of the copolymer has also been investigated. The obtained copolymers were extensively characterized to determine their composition and thermal stability. The heat of reaction for the polymerisation of the halogenated key precursors has also been measured.

Copolymers of epichlorohydrin (ECH) and 1,2‐epoxyhexane (EpH) have been synthesized via cationic ring‐opening polymerization using BF3×THF as a catalyst. Structures of the resulting polymers have been confirmed by IR and NMR spectroscopy and GPC. In a subsequent reaction with NaN3 in DMSO, the halogenated precursors were completely azidated, which was confirmed by the same spectroscopic methods. The introduced pendant n‐butyl chains act as an internal plasticizer by lowering the glass transition temperature (Tg) of the copolymers compared to the reference compound glycidyl azide polymer (GAP). Compared to GAP in a similar molecular weight range, the copolymers also showed reduced viscosity. These properties make the described copolymers interesting candidates for use as energetic binders in cast‐cure applications.

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The main objective of these studies was the synthesis and characterization of new energetic binders and their use in some propellant formulations. Following the working plan elaborated, the synthesis and characterization of the following compounds has been done successfully:The scale up for the synthesis of copolymer GAP/PolyBAMO and PolyBAMO using GAP as initiator has been done and they were fully characterized by IR, ( 1 H, 13 C) NMR-spectroscopy, GPC, elemental analysis, OH-functionality, differential scanning calorimetry (DSC) and sensitivity tests (friction, impact). For this two scale up synthesis some propellant formulations were carried out and the results of mechanical and burning properties have been compared with GAP propellants.

Poly(3-azidomethyl-3-methyloxetane) and its copolymers with 3,3-bis(azidomethyl)oxetane were synthesized by cationic polymerization from 3-tosyloxymethyl-3-methyl oxetane and 3,3-bis(bromomethyl)oxetane, using a polyol as initiator and boron trifluoride complex as catalyst, followed by azidation. The final objective is the synthesis of an energetic binder to be used for rocket propellants and therefore the effects of different initiator/catalyst systems on important properties, like, i.e., the molecular weight distribution and the functionality of the polymer, were investigated. It was found that, even though both the operating conditions and the catalytic system were chosen in order to grant the living character of the polymerization, the latter seems to be prevalently driven by an "active chain end" mechanism. In particular, this may lead to the undesired formation of a small quantity of oligomers and to the presence of non-hydroxylic chain-end functionalities. Nevertheless, the average number of OH groups can be strictly controlled when boron trifluoride tetrahydrofuranate is used as catalyst.

This study shows the in¯uence of RDX, Al and AP on the performance and reaction behavior of underwater explosives. The studied explosives varied in formulation, aluminium particle size and aluminium arrangement in the matrix. The different explosives were characterized by analyses of the detonation products after blasting in a closed vessel. The performance was measured by underwater explosions of charges with weights of 70 g, 250 g, 500 g and 1000 g.