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Industrial zeolitic membranes which offer a remarkable selectivity compared to polymeric membranes, suffer of the lower flux due of their larger thickness (e.g., 10-30 lm). This problem can be addressed by controlled synthesis of nanolayers, resulting in thinner membrane layers (e.g., 0.5-5 lm). An aluminosilicate gel with a molar composition of 20SiO 2 :Al 2 O 3 :10K 2 O:400H 2 O was used to prepare several membranes of zeolite L by means of a controlled hydrothermal synthesis on the surface of a porous alumina disc seeded with nanozeolite LTL crystals. Nanocrystallites of LTL zeolite with an average particle size of 80-100 nm were successfully synthesized and characterized. Using these nanoparticles as seeds, a zeolite L layer with an average thickness of 2 lm was synthesized on the alumina support at 150°C.

Glycidyl azide polymer (GAP) is well known as an energetic prepolymer, but its application as a binder in propellants is limited due to its relatively high glass transition temperature and relatively poor mechanical properties. Copolymerization of GAP with polypropylene glycol (PPG) has been shown to improve GAPs properties because of the good thermal and mechanical properties of PPG. In this research we synthesized triblock copolymer of PPG-GAP-PPG and the compatibilities of this copolymer were investigated with energetic plasticizers (20% w/w) n-butyl nitroxyethylnitramine (BuNENA), trimethylolethane trinitrate (TMETN), and butanetriol trinitrate (BTTN) by solubility parameter, differential scanning calorimetry (DSC), rheological analysis, scanning electron microscopy (SEM) and vacuum stability test (VST). The DSC results showed that BuNENA had better compatibility with the triblock copolymer in comparison to TMETN and BTTN. It reduced the Tg of PPG-GAP-PPG from −58 to −63 °C. The rheological analysis was in good agreement with the DSC results obtained for the compatibility of the plasticizers. In the case of the addition of 20% w/w BuNENA, the viscosity of copolymer/plasticizer decreased from 550 to 128 mPa s, indicating appropriate compatibility of plasticizer with the copolymer. SEM images showed a better distribution of BuNENA in the copolymer matrix.

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