NOVEL NYLON/HALOGENATED BUTYL RUBBER BLENDS IN PROTECTION AGAINST WARFARE AGENTS Marek Gnatow ski, Polymer Engineering Company Ltd, Burnaby, B.C., Canada J.D. ( Jack) Van Dyke, Trinity Western University, Langley, B.C., Canada Andrew Burczyk, Defence R&D Canada-Suffield, AB, Canada
Polymeric Materials in Protective Gear Special Gear to Protect Humans and Resources Against an Aggressive and Hostile Environment � Space � Underwater � Natural or man made disasters � War
Polymeric Materials in Protective Gear Polymeric Materials are Used in Protective Gear for the Following Reasons: Wide range of mechanical properties � Relatively resistant to hostile and aggressive environment � (if properly selected) Easy moulding � Wide range of coefficient of friction � Light weight � Variety of colours �
Polymeric Materials in Protective Gear Materials Properties Modulus of Density Barrier Elastom eric Coefficient Elasticity Material Behaviour of Friction Properties g/ cm 3 MPa Yes Polymers Variable 10 – 40,000 0.8 – 2.3 0.05 - 4 (in selected materials) Metals No Excellent 300 – 400,000 2 - 20 0.15 - 5 Ceramics and No Excellent 200,000 – 450,000 2.5 - 6 0.6 - 1 Glasses
Polymeric Materials in Protective Gear Properties of selected commercial polymeric materials Resistance to Mechanical Behaviour Processing Material Oil and Engineered Friendly CW d Water* Elastomer Fuels Plastic Butyl, Halogenated Butyl (C,B) IIR 4 4 1 1 4 2-3 Rubber Natural Rubber NR 1 1-3 1 1(3) c 4 2-3 (polyisoprene) Chloroprene CR 1-2 2-3 4 1 4 2-3 Nitrile Rubber NBR 1-2 3 4 1 4 2-3 Santoprene (PP/EPDM) TPE 1 3 1-2 1 4 4 Polyurethane Elastomer PU 1-2 2-3 3-4 1 4 3-4 3 (1) a Polyamides (Nylons) PA 3-4 4 4 1 3-4 Aromatic Polyesters PET, PBT 4 4 (2) a 4 4 1 3-4 (PBT, PET) 1-3 b Polyvinyl Alcohol (PVOH) PVA 2-4 1 4 3 1 Polystyrene PS 1 4 1 2-3 1 4 HDPE HDPE 1 4 3-4 2-3 1 4 4 – excellent 3 – good 2 – acceptable 1 – unacceptable a. immersion in hot water b. requires modification c. ebonite d. CW – chemical warfare agent * long term exposure
Polymeric Materials in Protective Gear Easy Moulding � Compression moulding � Injection moulding � Extrusion
Materials Selection for Blending A. Nylon 12 Excellent barrier properties � Excellent mechanical properties � Relatively low processing � temperature (190 – 220 o C) Commercially available � B. (Halogenated) Butyl Rubber Good mechanical properties � Good warfare agent resistance � Commercially available �
Nylon Chlorobutyl Rubber Blend Challenges in Blending � Physical incompatibility of nylon and halogenated butyl rubbers � Incorporation of over 50% rubber into the blend � Maintaining thermoplastic properties and good mechanical properties of blend
Nylon Chlorobutyl Rubber Blend Blending Procedure Batch Mixing Extrusion
Nylon Chlorobutyl Rubber Blend The Dynamic Vulcanization Process regular blending dynamic vulcanization
Nylon Chlorobutyl Rubber Blend Potential Compatibilization of Blend O H H N N N H O O + CH 2 * O H H N N N H O O
Nylon Chlorobutyl Rubber Blend % Insolubles – Non-vulcanized vs. Dynamically Vulcanized 120 100 % Insolubles Non Vulcanized 80 60 Dynamically Vulcanized 40 20 0 Butyl Bromobutyl Chlorobutyl
Nylon Chlorobutyl Rubber Blend Comparison of Tensile Strength Non-vulcanized vs. Dynamically Vulcanized Ultim ate Tensile Strength (MPa) 16 14 12 10 8 6 4 2 0 R V R V R V D D I I I D I I I / B C R R 2 R / / 1 2 2 I I I I I A I 1 1 B C / 2 A A P / / 1 2 2 P P 1 1 A A A P P P
Nylon Chlorobutyl Rubber Blend Comparison of Elongation Non-vulcanized and Dynamically Vulcanized 400 350 Elongation at Break (%) 300 250 200 150 100 50 0 R V R V R V I D I D I D I I I B C / 2 R R R / / 1 2 2 I I I A I I I 1 1 / B C 2 A A P / / 1 2 2 P P A 1 1 A A P P P
Nylon Halogenated Rubber Blend Swelling index and elongation at break for dynamically vulcanized blends in CHCl 3 7 300 Swelling Index 6 Elongation at Break 250 Elongation at Break 5 Swelling Index 200 4 150 3 100 2 50 1 0 0 0 10 20 30 40 50 60 70 80 90 100 % Polyamide
Nylon Halogenated Rubber Blend Blend Microstructure
Nylon-Chlorinated Butyl Rubber Blend Effect of Moulding Conditions on Tensile Strength and Elongation at Break Testing according to ASTM D 638M, specimen type M-III 50 300 45 PA12/CIIR PA12/CIIR PA12/CIIR 40/60 PA12/CIIR 40 Tensile Strength at Break (MPa) 40/60 250 30/70 30/70 ) Elongation at Break (% 35 Tensile strength at 200 30 break 25 Elongation at 150 break (Video) 20 15 100 10 50 5 0 0 Injection Moulding Injection Moulding Compression Compression Extrusion Extrusion
Nylon-Chlorinated Butyl Rubber Blend Effect of Moulding Conditions on Tensile Modulus Testing according to ASTM D 638M, specimen type M-III 450 400 PA12/CIIR PA12/CIIR 350 PA12/CIIR 40/60 PA12/CIIR 40/60 Modulus (Mpa) 300 30/70 30/70 250 200 150 100 50 0 n n n n g g o o o o n n i i i i i i s s s s d d s s u u l l u e u e r r o r t o r t x x p p M M E E m m n n o o o o C C i i t t c c e e j j n n I I
Nylon-Chlorinated Butyl Rubber Blend Effect of Moulding on Hardness Testing according to ASTM D 638M, specimen type M-III 60 55 50 Shore D Hardness PA12/CIIR PA12/CIIR 45 40/60 PA12/CIIR 40/60 PA12/CIIR 30/70 40 30/70 35 30 25 20 Compression Extrusion Compression Extrusion Injection Moulding Injection Moulding
Nylon-Chlorinated Butyl Rubber Blend Effect of Flow in Mould on Mechanical Properties 50 PA12/CIIR 300 45 PA12/CIIR Tensile Strength at Break (MPa) 40/60 40/60 40 PA12/CIIR PA12/CIIR 250 Elongation at Break (%) 35 30/70 30/70 200 30 25 150 Die cut 20 Tensile strength at 15 100 break (Mpa) 10 50 Elongation at 5 break (Video) (%) 0 0 As Moulded cut from As Moulded cut from Impact Bar Impact Bar 450 Injection 400 moulded PA12/CIIR PA12/CIIR 350 PA12/CIIR PA12CIIR 30/70 40/60 ) 300 40/60 30/70 a p (M 250 s lu u 200 d o M 150 100 50 0 As cut from As cut from Moulded Impact Bar Moulded Impact Bar
Nylon-Chlorinated Butyl Rubber Blend Effect of Flow on Blend Microstructure
Nylon-Chlorinated Butyl Rubber Blend Penetration* for all samples was 0 µg at testing conditions Reemission* vs. Nylon Content in Blends 60 50 Re-emission (µg) 40 30 ZDEDC / ZnO 20 Sulfur 10 0 15 20 25 30 35 40 45 Nylon Content (Wt%) * method of testing described in C.L. Stevens presentation “Nylon-12 Nanocomposite Thin Films as Protective Barriers”
Polymeric Materials in Protective Gear New Development of Special Polymeric Materials Will Bring Revolutionary Changes to Protective Equipment Increase protection efficiency � Decrease the burden on personnel � Decrease manufacturing costs � Post World War II The Future 1980’s
Conclusions 1. Nylon can be blended with butyl or halogenated butyl rubber to obtain material with thermoplastic elastomer properties 2. Properties of the blends depend on nylon/ rubber ratio, mixing conditions, and vulcanizing agent used 3. Mechanical properties also depend on moulding conditions and mould geometry 4. Nylon-chlorobutyl thermoplastic elastomers showed excellent resistance to penetration and reemission of warfare agents 5. Nylon-chlorobutyl blends showed significantly better resistance to hydrocarbon and chlorinated hydrocarbon solvents than could be expected from the rubber content in the blend
Acknowledgments Laboratory Support Polymer Engineering Company Materials Suppliers Andrew Koutsandreas � Exxon Mobil � Dave Lesewick � Bayer � Christine Mah � EMS Grivory Beverley Start � � Kate Mao � Trinity Western University Andrea Lengkeek � Leanne Edwards � Sebastian Temple � DRDC - Dockyard Laboratory Pacific Bruce Kaye � DRDC – Suffield Benoit Lacroix �
Recommend
More recommend
