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Published byLindsey Blankenship Modified over 9 years ago
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Elastic modulus of PETP: changes during fibre drawing
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Hall: Polymer Materials, 2nd edn
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Polymer viscoelasticity Maxwell element D Hookean elastic spring Viscous element dashpot
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Polymer viscoelasticity Maxwell element D At constant applied stress
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Polymer viscoelasticity Maxwell element D At constant applied strain
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Polymer viscoelasticity Kelvin-Voigt element D
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Polymer viscoelasticity Standard linear solid D1D1 D2D2
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ADHESIVES Many commercial adhesives Four examples Polymer cement: polystyrene Latex or emulsion type: EvoStik PVA Epoxy: thermoset Araldite Cyanoacrylate: Loctite, Glasbond
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ADHESIVES Polystyrene cement Solid PS polymer + solvent Liquid adhesive Bonds by solvent evaporation Yes, it’s that simple.
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Latex or emulsion type adhesive EvoStik Spherical polymer particles dispersed in water Ma, Davis and Scriven Prog Org Coatings 2005, v52, 46-62
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Latex coalescence Film formation As water is lost, particles come into contact and merge Ma, Davis and Scriven Prog Org Coatings 2005, v52, 46-62
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Super-glue Cyanoacrylate adhesives The uncured adhesive consists of a monomer commonly CH 2 =C-COOCH 3 The polymerisation reaction is triggered by traces of water, generally present on the surface to be bonded CN
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Melting temperatures of common polymers Polyethylene PE 100 °C Polypropylene PP 130 °C
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Hall: Polymer Materials, 2nd edn Polymer forming: extrusion
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Hall: Polymer Materials, 2nd edn Polymer forming: extrusion injection moulding
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Hall: Polymer Materials, 2nd edn Polymer forming: extrusion injection moulding rotational moulding
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Hall: Polymer Materials, 2nd edn Polymer forming: extrusion injection moulding rotational moulding blow moulding
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Hall: Polymer Materials, 2nd edn Polymer forming: simple extrusion Granules of raw thermoplastic IN Increasing temperature along the extruder barrel Extruded product OUT
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Hall: Polymer Materials, 2nd edn Polymer forming: simple extrusion Granules of raw thermoplastic IN Increasing temperature along the extruder Die swell Extruded product OUT
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Polymer forming: injection moulding
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Polymer forming: rotational moulding
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Polymer forming: blow moulding
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Netlon process for mesh Hall: Polymers, in Civil Engineering Materials, 5nd edn
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Netlon process: 1992 patent (one of many)
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Netlon process for mesh Hall: “Polymers”, in Civil Engineering Materials, 5nd edn, Pt VI
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Netlon process for mesh Hall: “Polymers”, in Civil Engineering Materials, 5nd edn, Pt VI
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