Basic Concept
What are the two main categories of plastic?
Thermoset & Thermoplastic
which thermoplastics have high reusability and recyclability?
Number 1 (PET); Number 2 (HDPE); Number 5 (PP)
What are the properties for plastic number 1?
transparent,lightweight
Please give one usage of a plastic material in plastic number 7 (Other)
ABS Plastic：3D-printing filament, toys, electronic products
PC Plastic：CDs／DVDs
PLA Plastic：bioplastics
Which plastic can be put into the microwave oven? Give the plastic number.
Number 5 (PP)
What number does HDPE plastic have?
Number 2 (HDPE)
Which two plastics has a medium reusability & recyclability?
Number 4 (LDPE); Number 6 (PS)
Which plastics is most commonly seen on market?
Number 1 (PET); Number 5 (PP)
Which number does straw belongs in?
Number 5 (PP)
Which type of plastic is considered the most dangerous? Why?
Number 7: very toxic gases can be emitted when burned
How many types of plastics are there in the category of thermoplastic?
7
Which plastic has a high but complex reusability & recyclability?
Number 1 (PET)
What are the properties for each of the main two categories of plastics?
Thermoset: cannot be melted and is solidified forever once it take shape
Thermoplastic: is soft and malleable when heated; hard and solid when cooled
Which plastic number does pipes and fake leather belongs in?
Number 3 (PVC)
What number does the LDPE plastics have?
Number 4 (LDPE)
Which 3 types of plastics are complicated to process when recycling?
Number 1 (PET); Number 4 (LDPE); Number 6 (PS)
Name three plastics that is heat insulating
Number 3 (PVC); Number 4 (LDPE); Number 5 (PP)
Please give 4 usages of the plastics under number 7 (Others)
3D-printing filament, toys, electronic products, CDs, DVDs, bioplastics
Which two plastics can cause cancer when in process/being burned? Why?
Number 3 (PVC) & 4 (LDPE):toxic gases are produced when heated
Why is it dangerous to mix different plastics?
mixed plastics has low plastic quality & is extremely difficult to recycle; the gas emitted from recycling mixed plastics is the most dangerous
Which two plastics has low reusability and recyclability?
Number 3 (PVC); Number 7 (Others)
Choose 3 types of thermoplastics and point out each of their Pros and Cons
Number 1:
Pros：reusable after cleaning, stiff, oxide barrier
Cons：high mold shrinkage, harmful gases may be produced when processing
Number 2:
Pros:high chemical resistance
Cons:high mold shrinkage, poor UV resistance, the additives emitted from burning may be hazard
Number 3:
Pros:high malleability, cheap
Cons:difficult to clean, toxic gases is produced when overheated which can lead to cancer
Number 4:
Pros:cheap, good processability
Cons:difficult to clean, couldn’t heat up
Number 5:
Pros:can withstand high temperatures, the only plastic that can be put into oven, can be reuse after cleaned
Cons:more expensive compared to PET, poor UV resistance
Number 6:
Pros:cheap, low mold shrinkage
Cons:brittle, low chemical resistance
Number 7:
Pros:ABS and PLA is recyclable despite of the fact that most plastic in this category could not
Cons:not identifiable
Please give 3 usages of PS plastic
Styrofoam, Disposable tableware, Cups from fast food restaurant
Bonus (Doubled Points): Draw the labels for all 7 plastics and give a usage for each.
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