The International Association of Plastics Distributors How Plastics

The International Association of Plastics Distributors How Plastics are Made Understanding the Physical Properties of Plastics Prepared by the IAPD Education Committee (Module 1) Presented courtesy of Modern Plastics, Inc. The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Processing • Injection molding • Extrusion – Ram extrusion – Screw extrusion – Coextrusion • • • Casting Compression molding Rotational molding Transfer molding Calendering The IAPD Plastics Primer, Module 1 • • Hand (or spray) lay up Laminating Filament winding Polymer orientation

The International Association of Plastics Distributors Injection Molding The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Extrusion • Ram • Screw • Coextrusion The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Casting Base Material Reactive Additive Oven Casting Mold The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Compression Molding • Sheet and block molding • Parts molding Mold Lid Mold The IAPD Plastics Primer, Module 1 Resin

The International Association of Plastics Distributors Rotational Molding • • Low cost Low pressure Used in many markets Easily adapted for short production runs The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Transfer Molding Widely used in the semiconductor industry The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Calendering The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Hand (or Spray) Lay Up • Used to make large parts • Used to produce fiberglass boats and camper shells The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Laminating Resin Binder Reinforcing Substrate Heat and pressure applied to the top and bottom of the material The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Filament Winding • Used to make containers and tubes • Items used for transportation of liquids or gasses The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Polymer Orientation Used to manufacture polymer fibers, strapping, webbing, film, sheet and profiles The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Plastics Fabrication • • • CNC machining centers CNC lathes Cutting and drilling Profiling Routing and milling Thermoforming Forging Milling Welding Bending Bonding The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Thermoforming • Single station thermoforming • Rotary station thermoformers • Pressure forming • Twin sheet thermoforming The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Welding • • • Extrusion welding Hot gas welding Butt welding Spin welding Solvent welding The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Bonding The union of materials by adhesives; to unite materials by means of an adhesive The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors The Performance of a Plastic Part is Affected By: • • • Type of load Size and application of load Frequency of application of load Speed of load Temperature the part will see, and for how long Use and environment of load The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Mechanical Properties • • • Tensile strength Elongation Compressive strength Creep Shear strength Flexural strength The IAPD Plastics Primer, Module 1 • • • Torsional strength Modulus Impact strength Specific gravity Water absorbtion Coefficient of Friction (COF)

The International Association of Plastics Distributors Testing Organizations • AFNOR - Association Francaise de Normalisation (France) • BSI - British Standards Institution (UK) • IEC - International Electrotechnical Commission • JIS - Japanese Industrial Standards The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Tensile Strength The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Elongation The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Compressive Strength • Measured in pounds per square inch (PSI) • Higher PSI = harder to compress The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Creep • Associated with compressive strength • Creep at room temperature is called “cold flow” The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Shear Strength The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Flexural Strength The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Torsional Strength The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Modulus • Also referred to as “stiffness” • Used in conjunction with strengths (flexural modulus, tensile modulus, etc. ) • Higher modulus = stiffer material • Measured in PSI The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Impact Strength Izod Impact The IAPD Plastics Primer, Module 1 Tensile Impact Gardner Impact

The International Association of Plastics Distributors Specific Gravity • Related to the density of material • Can be used to determine the weight of material • Specific gravity of less than 1. 0 will float in water The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Water Absorption • Measured by the percentage of swell • Think of a sponge as having high percentage absorption The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Coefficient of Friction (COF) • Resistance to sliding (slickness) • Low COF = more slippery (think of “wet ice” as having lowest COF) • Static COF refers to initial movement from rest • Dynamic COF refers to being already in motion The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Thermal Properties • Coefficient of thermal expansion • Heat deflection temperature • Continuous service temperature • Melting point • Thermal conductivity The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Coefficient of Thermal Expansion (CTE) • Change in size as temperature changes • Lower value = less change with temperature The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Heat Deflection Temperature (HDT) • Temperature up to which a material can perform, under load, without distorting • Measured in degrees Fahrenheit, usually under 264 PSI • Used most widely to predict performance The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Continuous Service Temperature (CST) • Highest temperature a material can withstand still retain at least 50% of its properties • Measured in degrees Fahrenheit, in air • In high temperatures, both CST and HDT must be considered The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Melting Point Temperature at which a crystalline thermoplastic changes from solid to liquid The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Thermal Conductivity • How much heat a material will conduct • Most plastics are good “insulators” (do not conduct heat well) • Higher value = more heat conducted • Thermal conductivity of plastics is 300 to 2, 500 times less than most metals The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Electrical Properties • Volume resistivity • Surface resistivity • Dielectric constant • Dielectric strength • Dissipation factor • Arc resistance • Flammability The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Volume Resistivity • Ability of electricity to flow through a material • Measured in ohms/cm • Lower value = more easily current flows • Higher value = better resistor or insulator The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Surface Resistivity • Ability of electricity to flow over the surface of a material • Same measurements as volume resistivity • Used to evaluate material when static discharge characteristics are critical The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Surface Resistivity Conductive Range 1 1 10 10 2 3 Static Dissipative Range 4 10 10 10 9 5 10 11 12 10 10 Shielding Range 10 6 10 7 106 to 108 The IAPD Plastics Primer, Module 1 Insulative Range Critical Range for ESD Control 10 8 20 10

The International Association of Plastics Distributors Dielectric Constant That property of a dielectric that determines the electrostatic energy stored per unit volume for unit potential gradient The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Dielectric Strength • Effectiveness of material as an insulator • Measured in volts/. 001 thickness • Higher value = better insulator • Voltage is increased until material arcs, showing a breakdown The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Dissipation Factor Tangent of the loss angle of the insulating material The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Arc Resistance Time required for an arc to establish a conductive path on the surface of an organic material The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors Flammability • Measured by UL 94 ratings • Most favorable ratings are given to materials that extinguish themselves rapidly, and do not drip flaming particles • Scale from highest burn rate => most flame retardant is HB, V-2, V-1, V-0, 5 V The IAPD Plastics Primer, Module 1

The International Association of Plastics Distributors The IAPD Plastics Primer, Module 1