classification of plastics - thermo plastics and thermo setting plastics.General explanations of plastics.

1. lets travel with

2. plastics
In general any non metal that can be moulded into desired
shape is called plastics.
They may be synthetic or natural resins or their compounds
which can moulded and can be used as commercial
products

3. FACTSABOUTPASTICS

4. Plastics are generally classified into
two major types
1.Thermoplastics
2.Thermo setting plastics
THERMOPLASTICS THERMOSETTINGPLASTIC

5. thermoplastics
Thermoplastics can soften upon
application of heat with or
without pressure provided
temperature should be less than
the decomposition temperature
of plastics.

6. CHARACTERISTICSOF THERMOPLASTICS
Reason Behind This Behavior(vanderwaal’s
forces)
Easy for moldings
Low melting temperature and are not so
strong
High resale value
Important thermos plastics and their
decomposition temperature
Polymer
Melting
Temperature
(oC) 1
Decompositi
on
Range2
polyethylene
(PE)
135 335-450
polypropylen
e (PP)
170 328-410
polyvinyl
chloride
(PVC)
265 200-300
polytetrafluor
o-
ethylene
(PTFE)
335 500-540
polystyrene
(PS)
242 300-400
nylon 6,6 268 310-380
polyethylene
terephthalate
(PET)
268 283-306
polycarbonat
e
(PC)
(150)4 420-620
polyaramid
--- 425-550
polyurethane
,
polyether
foam
--- ---
cellulose
(wood)
--- ---

7. Structure of thermosplastics

8. Thrmosetting plastics
Plastics that need heat as
well as pressure to mold
them are called
thermosetting plastics.

9. Characteristicsof thermosetting plastics
• One main advantage
• Molecular structure
• Reason behind hardness

10. Structureofthermosettingplastics

11. DIFFERENCEBETWEENTHERMOPLASTICSANDTHERMOSETTINGPLASTIC
THERMOPLASSTIC THERMOSETTING
PLASTIC

12. THERMOPLASTICS
• Soft and less
strong.
• Repeatedly
softened.
• Cannot use at
high temperature.
• Complicated
molds.
• Can be recycled.
THERMOSETTING
PLASTICS
• More stronger
and harder.
• Hardened only
once.
• Can be used at
high temperature.
• Simple molds.
• Cannot be
recycled.

13. recycled
PROPERTIESOF PLASTICS
• Specific gravity/density
• Specific heat(200-800)
• Thermal conductivity
• Thermal expansion
• Electrical properties
• Corrosion resistant
• Combustibility
• rigidity

14. Just think