Rheological Capabilities at TACOM-ARDEC Presented by: Leslie Fishbein Armament Systems Process Division WECAC

Purpose Provide an overview of efforts to establish a state-of-the-art energetic materials characterization laboratory at TACOM-ARDEC

Outline Mission Equipment Capabilities Future Work Summary

The TACOM-ARDEC Mission The Rheology Laboratory will enhance TACOM-ARDEC’s role as a leading developer of new energetic compositions and processes: FCS propellants in support of the Multi-role Armament and Ammunition System (MRAAS) State-of-the-art processing of energetic materials at the Building 1403 Twin-Screw Mixer/Extruder Process modeling and simulation Support of items in production (e.g., M30A1, JA-2, AA-2, PAP-7993, M14, Ball Powders) Opportunities to team with Industry and Academia: Stevens Institute of Technology (SIT) Polymer Processing Institute, New Jersey Institute of Technology (NJIT) ATK/Radford AAP GENCORP Aerojet ATK/Thiokol Propulsion

The Rheological Laboratory Consolidate rheological capabilities under one roof: Remotely operated systems User friendly software for data acquisition and analysis Support TACOM-ARDEC material characterizations: Energetic materials (Propellants, Explosives, Pyrotechnics) Precursor Materials (e.g., ETPEs, binders) Plastics Epoxies Composites Resins Support process modeling and simulation efforts: Twin-Screw Mixer/Extruder Shear Roll Mill Cryogenic Polymerization Reactor

Capillary Rheometer Similar to laboratory-scale extruder that is highly instrumented and accurately controlled Relate changes in processing conditions (pressure, temperature) of extrusion to product properties (mechanical, ballistic) Characterize the rheological/flow properties of energetic materials under different conditions (temperature, composition) Obtain a constitutive equation for the energetic materials for process analysis and simulation using RheoPlotter software Instron Load Frame Model #5581 and Shear Tool Capillary Adapter Assembly

Capillary Rheometer To determine the rheological properties as a function of shear rate, temperature, pressure, and molecular weight, which is crucial to the design and control of process operation Apply Different Speeds (S) at controlled Temperature Reservoir Capillary Plunger S ~ Obtain Forces (Resistance to Flow) Data Analysis Viscosity = F (shear rate, temperature) Relate To Die Forming Flow in Processing Equipment

Rheometric Scientific Dynamic Analyzer- RDA III Rotational Rheometer Study the dynamic mechanical properties of the energetic materials (G, G, tan ) Study the complex viscosity (*) and viscoelastic behavior Investigate the molecular structure and interaction/compatibility between the ingredients of the energetic materials Study the reaction kinetics of reactive system Rheometric Scientific Dynamic Analyzer- RDA III

Rotational Rheometer Measures viscosity, elasticity and shear modulus Can perform controlled strain, stress and strain rate experiments Includes range of test fixtures: Parallel plate Torsion fixtures Allows for characterization from: Suspensions, emulsions, Polymer melts, elastomers Solids Apply Strain A=A0sint where A0: small amplitude Measure Torque, Normal Force Obtain Normal Force, Torque Torque = T sin t + T cos t Data Analysis Elastic Properties Viscous Properties Apply Strain A=A0sint Relate To “Structure” of the Mixture (MW, concentration, degree of mixing, compatibility, crosslinking)

Torque Rheometer The Poly Lab 300p enables production of small batches with simultaneous recording of torque and time while mixing material: High torque capability Oil heated and cooled chamber and plates Rotors for different shear ranges: Roller blades (viscous properties for thermoplastics & thermosets) Cam blades (thermoplasts & elastomers in medium shearing range) Banbury blades (natural and synthetic rubber) Sigma blades (low shear ranges; most suitable f/energetic materials) Teflon bushings to test chemically aggressive media Special tools to clean the mixer parts Pneumatic ram Poly View data evaluation; i.e.: Routine evaluation --Rheograms (torque vs. time) Multi curve Analysis

Thermo Haake Poly-Lab 300p System Torque Rheometer The torque rheometer is capable of the measuring the following: Dynamic viscosity depending on shear load Melt behavior in the extruder The influence of additives Temperature and shear load behavior TACOM-ARDEC will mainly be using Rheometer for it’s mixing capabilities Thermo Haake Poly-Lab 300p System

Internal Mixer Torque Rheometer Apply rpm () = Constant at Controlled Temperature Obtain Torque (time) Data Analysis Specific Energy Requirement for Mixing, Reaction = F (time) Relate To Mixing, Reaction = F (axial distance) in an extruder

Planned Work Loading – FY 03 Army Characterization of JA-2 and AA-2 propellant produced on a Shear Roll Mill (ManTech) Supports modeling activity w/SIT Leveraged with implementation of SRM technology in support of the manufacture of solventless propellants at Radford AAP Characterization of ETPEs (ManTech) Supports TACOM-ARDEC modeling activity and ETPE process optimization Begin developing of rheological data base for energetic materials consider for TSE processing (ManTech) Propellants (e.g., M39 / M43 LOVA) Explosives (e.g., PAX-2A IM) Pyrotechnics (e.g, M206, MJU-7A/B, MJU-53/B) 155-mm M485 Illumination Round Characterization of replacement material for liquid polysulfide

Planned Work Loading Initiatives Potential (3rd party) ATK / Radford AAP (gun propellants): Full-time PhD Rheologist -- no laboratory capability ATK / Thiokol Propulsion (rocket and gun propellants) GENCORP Aerojet (CRADA tasking) BAE Systems / Holston AAP (explosives) SIT (in support of process modeling) PPI, NJIT (CRADA): Expand PPI commercial market place through use of Rheology Laboratory at TACOM-ARDEC

Summary Rheology Lab is in full operational status The characterization of Energetics is to be used to understand, simulate, design, and optimize the manufacturing processes CRADA has been signed with PPI/NJIT Future work is being discussed with SIT, ATK, and Aerojet Questions and Inquires to be addressed to: Lilia Mastov TACOM-ARDEC (973)724-3351 lmastov@pica.army.mil