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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 Impact Strength Izod ImpactTensile ImpactGardner Impact

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

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

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

The International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 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 International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 Continuous Service Temperature (CST) Highest temperature a material can withstand and 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 International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 Melting Point Temperature at which a crystalline thermoplastic changes from solid to liquid

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

The International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 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 International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 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 International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 Surface Resistivity to 10 8 Critical Range for ESD Control Shielding Range Conductive Range Static Dissipative Range Insulative Range

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

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

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

The International Association of Plastics Distributors The IAPD Plastics Primer, Module 1 Measured by UL94 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, 5V Flammability

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