Munguia Flashcards
Definition - Polymer
A chemical substance consisting of large molecules made from many smaller and simpler molecules
Definition - Thermoplastic (semi-crystalline)
A polymer with a mixture of both crystalline and amorphous structures
Definition - Thermoplastic - amorphous
A polymer with no crystalline structures
Definition - Thermoset
A polymer that irreversibly becomes rigid when heated (crystalline)
Properties - Thermoplastic (semi-crystalline) MP
Do not soften as temperature rises, have defined and narrow melting point
Properties - Thermoplastics (amorphous) MP
Gradually deform as the temperature rises, no set melting point
Definition - Elastomer (Thermoplastic)
A natural or synthetic material which is capable of recovering their original shape after being deformed to great extents.
Definition - Elastomer (Thermoset)
Rubber materials (natural or synthetic) polymer macromolecules, can be polymerised.
Name 3 semi-crystalline Thermoplastics
HDPE PE PEEK PEK PET POM PP
Name 3 amorphous Thermoplastics
ABS COP PC PS SAN PCL
Name 3 Thermosets (plastics)
Polyester Polyurethane PF Melamine Epoxy
Name 3 Elastomers
Thermoplastic -
TPU
TPS
TPO
Thermoset - BR Neoprene Styrene Nitrile rubber
Name a difference between SC and A Thermoplastics
Semi- crystalline:
- Remain solid until a given quantity of heat is absorbed, then change into low viscosity liquid
- excellent chemical resistance
- Highly ordered Molecular structure
Amorphous:
- Don’t have a sharp melt point, softens gradually as temp rises
- change in viscosity when heated
- Randomly ordered Molecular structure
ABS - Properties and uses
High impact strength Good toughness Scratch resistant Lightweight Durable Food grade
Pipes PC monitor cases Keyboard keys Power tool housing Refrigerator linings Food processors Toys
Nylon - Properties and uses
Hard
Tough
Resistant to wear
Low coefficient of friction
Bearings
Gears
Clothing
PMMA(acrylic) - Properties and uses
Food safe Tough Hard Durable Easily machined
Light units
Lenses for car lights
Tupperwares
PP - Properties and uses
Lightweight
Food grade
Good impact resistance
Good chemical resistance
Kitchen products Medical equipment String and rope Bottles Jars Pallets Food packaging
SLS process
Selective Laser Sintering - Laser fuses polymer powder Low cost per part High productivity No support structures Excellent mechanical properties
Best for:
Functional prototyping
End use production
SLA process
Stereolithography
Laser cures photopolymer resin
Highly versatile material selection
Highest resolution and accuracy, fine details
Best for: Functional prototyping Patterns Molds Tooling
FDM modelling
Melts and extrudes Thermoplastic filament
Lowest price of entry and materials
Lowest resolution and accuracy
Best for:
Basic proof of concept models
Simple prototyping
