Polyethylene

1. What is Polyethylene?

2. Processes for Polymerization of
Ethylene
A. High Pressure Processes
Conventional process, Slurry Process, Solution Process
B. Low Pressure Processes
Zieglar Process, Unipol Process, Philips Process, Indiana Process,
Other processes.

3. Commercial PE Production
Technologies

4. Conventional process for LDPE
 .

5. Autoclave reaction process and recycle system
.

6. Tubular reaction process

7. Long Chain Branching in LDPE(LCB)
 LDPE Density 0.918-0.919 g/cm3,MFI- 1.7 ,Mn = 200,000
 a. Autoclave Product with 20 LCB
 b. Tubular product with 7 LCB

8. Back-biting mechanism in LDPE

9. Peroxide Initiator for LDPE polymerization
Peroxide Half-life (1min.)
temperature (oC)
 T- Butyl peroxypivalate 123
 Dioctanyl Peroxide 127
 T-butyl peroxyisobutyrate 130
 T-butyl peroxybenzoate 170
 Di-t—butyl peroxide 191
 T-butyl hydroperoxide 260

10. Common Chain-Transfer Agents
 Methane, Ethane, Propane, Ethanol, Propylene, Acetone,
Hydrogen, iso-butylene, 2-butene, 1-butene

11. LDPE Copolymers
 Ethylene Vinyl Acetate (EVA)
 Ethylene Methyl Acrylate (EMA)
 Ethylene Acrylic Acid (EAA)

12. Typical Properties of LDPE

13. Property Comparison of LDPE and LLDPE

14. Blown film Plant

15. Viscosity Behavior under Shear for
LDPE and LLDPE

16. Viscosity Behavior under Extension for
LDPE and LLDPE

17. Effect of Molecular weight on LDPE
properties
 .

18. Effect of Density on Properties of LDPE

19. General properties of LDPE

20. Film and sheet Application
(MFI 0.2 to 6 and Density-0.917-0.930 g/cm3)
 Shrink Wrapping, heavy duty sacks, food
packaging.
 Storage bags, agricultural films and industrial
sheeting.

21. Extrusion Coating
(MFI 4 to 10 and Density-0.920-0.930 g/cm3)
 Thin coating on paper, aluminum foil,
paperboard and another polymeric film.
 Final structure is used for food packaging, juice
boxes, milk or another food container
 Advantage : LDPE serves as adhesive, moisture
barrier, seal layer, printing surface or barrier to
tearing.