Plastic material basics Chemistry Ways to classify What
Plastic material basics Chemistry Ways to classify What else than polymer in plastics Muoviteknologia Teppo Vienamo
Are all plastics the same? Muoviteknologia Teppo Vienamo
Features of plastics • • • Light Flexible Impact resistance Good corrosion resistance Good chemical resistance Easy to form Good insulator bad conductor Does not stand high temperatures Creep Cracking by tension Muoviteknologia Teppo Vienamo
Ways to classify plastics • Thermosets / thermoplastics /elastomers • Commodity polymers / engineering polymers / high performance polymers • Synthetic plastics / natural plastics Muoviteknologia Teppo Vienamo Expensive high performance polymers Price engineering polymers Cheap Commodity polymers Amorphous Crystalline Thermoplastics (Elastomeres) Thermosets
Polymer • Mineral oil = carbon + hydrogen + • Silicone oxide Muoviteknologia Teppo Vienamo
Plastics • Polymer • • Fillers Additives Reinforcements Pigments Muoviteknologia Teppo Vienamo
Polymer Addition polymerization • Pressure • Heat • catalyst Condensation polymerization • Water breaks out from joint Muoviteknologia Teppo Vienamo
Length of molecule =>mol mass • • • Methane CH 4 Pentane C 5 H 12 Solid paraffin Wax Plastics e. g. PE - LD gas fluid Entanglement and molecular weight increases to the right Strength increases to the right Muoviteknologia Teppo Vienamo
Amorphous plastics • Can be transparent • Small shrinkage • Poor chemical strength • PS, PVC, PMMA Muoviteknologia Teppo Vienamo
Crystalline polymer • Wear resistant • Big shrinkage • Good chemical strength • PE, PP, PET Muoviteknologia Teppo Vienamo
Chemical bond Secondary bond (weak) covalent bond(strong) Muoviteknologia Teppo Vienamo
Thermoplastics • Straight chains • From chain to an other weak force • Melts • Reformable Muoviteknologia Teppo Vienamo
Thermosets • Cross links • Does not melt by adding heat • Good heat resistance • Good mechanical strength Muoviteknologia Teppo Vienamo
Fillers over 10% Expense reduction Smaller shrinkage • • • calcite talc kaoline Glass balls Carbon Muoviteknologia Teppo Vienamo
Colour pigments • • Effects on plastics properties Natural colour of polymer Master batch, pasta, liquid and powder Less than 0, 1 % in a product Muoviteknologia Teppo Vienamo
Additives From fractions of % to some % • • • Softeners Lubricates UV-resistance Combustion modifiers Blowing agents Muoviteknologia Teppo Vienamo
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