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Systemic capillary leak syndrome (SCLS) is a rare disorder characterized by recurrent spontaneous episodes of hypovolaemic shock due to marked plasma shifts from the intravascular to the extravascular space. This presents as the characteristic triad of hypotension, haemoconcentration and hypoalbuminemia often with an associated monoclonal gammopathy. We describe a patient with SCLS who required aggressive fluid resuscitation and emergency fasciotomies for compartment syndrome with rhabdomyolysis. At presentation the patient was considered to have severe erythrocytosis and was therefore initially referred to a haematologist, which appears to be a frequent sequence of presentation for patients with SCLS. This patient also highlights the importance of muscle compartment pressure monitoring during volume resuscitation in patients with SCLS.

The surface morphology of thermooxidative degraded polystyrene–isoprene–styrene (SIS) and polystyrene–butadiene–styrene (SBS) thermoplastic block copolymers was studied by scanning electron microscopy. Surface changes caused by heating the samples in a pyrolyzer for 15 and 30 min were presented in different micrographs. The morphological changes occurring due to the formation of polar groups and their crosslinking during the thermooxidative degradation are discussed. Morphological study of these thermally degraded polymer samples shows very good correlation with the thermodegradation results. The rate of thermodegradation is fast in case of SBS when compared with SIS block copolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2549–2553, 2006

The surface morphology of thermooxidative‐degraded polystyrene–isoprene–styrene (SIS) and polystyrene–butadiene–styrene (SBS) thermoplastic block copolymers were studied by scanning electron microscopy. Surface changes caused by heating the samples in a pyrolizer for 15 and 30 min were presented in different micrographs. The morphological changes occurring due to the formation of polar groups and their crossing linking during the thermooxidative degradation are discussed. Morphological study of these thermally degraded polymer samples show very good correlation with the thermodegradation results. The rate of thermodegradation is fast in case of SBS compared with SIS block copolymer. ©2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Currently triple base propellants are used for tank gun ammunition. Nitroguanidine (NQ) propellant is the most promising among them due to various advantages like low flame temperature, flashlessness, low barrel erosion, long shelf life, etc. Therefore, it will continue to be used in the field of gun propulsion systems for several years to come. However, there is scope for enhancing the performance of triple base propellant with respect to energy level and mechanical properties. Nitrocellulose (NC) is the energetic binder cum fuel used in the triple base composition propellant and constitutes a sizeable percentage of the compound. Hence, one of the promising triple base compositions was selected, and a systematic study was carried out by using different types of NC (having varying percentages of nitrogen content) to study the variation in mechanical properties, energy content, linear burning rate coefficient, and pressure exponent. The results are discussed in this paper.

This paper presents the results obtained during studies on 80% RDX propellant systems based on thermoplastic elastomers (TPEs) namely ethylene-vinyl acetate (EVA), triblock copolymers of styrene-butadiene/styrene-isoprene (Kraton), poly-urethane-ester-MDI (Estane) and copolymer of polybutylene terephthalate - polyether glycol (Hytrel) as binders, Dioctyl phthalate (DOP), triacetin (TA) and glycidyl azide polymer (GAP) were incorporated as plasticizers in the formulations. An attempt has been made to correlate structural features of TPEs with mechanical properties as well as glass transition temperature (Tg). Results obtained suggest that TPE-based RDX-propellants have the advantage of high insensitivity to impact and friction stimuli vis-à-vis nitrte ester based conventional propellants. EVA based propellents gave the best results in this regard. Ignition temperature for all the compositions was >200°C. EVA, Hytrel and Estane based formulations were found to be more energetic than Kraton based formulations. Incorporation of GAP resulted in the improvement in ballistics (Impetus and burn rates) as compared to DOP plasticised formulations. TA based compositions gave an intermediate value. Thermal decomposition pattern was determined by applying Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). An attempt has been made to explain the trends observed on the basis of the evidences generated during this study and theories proposed by other researchers.

This paper presents the results of systematic studies carried out on the role of fine RDX in determining the burning rate and ballistics of LOVA gun propellants. Propellant formulations containing fine RDX particles with a size of 4.5, 6, 13 and 32 µm as energetic ingredient, cellulose acetate as inert binder, triacetin as inert plasticizer, nitrocellulose of lower percentage nitrogen content as energetic binder and carbamite as stabilizer were made. The evaluation of the propellant batches has been carried out by static firing using closed vessel technique. It indicates the linear relation between the burning rate of the propellant and the fine RDX particle size used in this formulation. The results of the present studies revealed that fine RDX of 4.5 to 6 µm size may be the most suitable for LOVA gun propellant to meet the desired burning rate for satisfactory ballistics.

This paper presents the results of systematic studies carried out on the role of fine RDX in determining the burning rate and ballistics of LOVA gun propellants. Propellant formulations containing fine RDX particles with a size of 4.5, 6, 13 and 32 µm as energetic ingredient, cellulose acetate as inert binder, triacetin as inert plasticizer, nitrocellulose of lower percentage nitrogen content as energetic binder and carbamite as stabilizer were made. The evaluation of the propellant batches has been carried out by static firing using closed vessel technique. It indicates the linear relation between the burning rate of the propellant and the fine RDX particle size used in this formulation. The results of the present studies revealed that fine RDX of 4.5 to 6 µm size may be the most suitable for LOVA gun propellant to meet the desired burning rate for satisfactory ballistics.