PET is produced from the polymerization of ethylene glycol and terephthalic acid. It has several advantages such as strength, light weight, and barrier properties. There are two main manufacturing processes for PET bottles - hot-perform and cold-perform. Both involve drying the PET, injection molding it into a preform, and then blow molding the preform into a container shape. A local Malaysian company called Apple Lady produces over 1300 plastic products including bottles using PET.

1. PET BOTTLE
Group Name : The Changes
Group Members:
1. Mohd Afiq Irfan Bin Syauqi
2.Agus Danish Hakim bin Agosmustaram
3.Nur Syamimi Binti Zainal Adelin
4.Muhammad Fadhlin Abqari Bin Nasli
Universiti Kebangsaan Malaysia
Faculty of Engineering & Built Environment
Department of Mechanical & Manufacturing Engineering

2. What is PET?
Polyethylene terephthalate or known as PET or PETE are produced by the
polymerization of ethylene glycol and terephthalic acid in presence of chemical
catalyst. The product which is PET is in the form of a molten, viscous mass that
can be spun directly to fibres or solidified for later processing as a plastic.

3. Molecular structure.

4. Advantage of PET
higher strength and
stiffness
very strong and
lightweight
good gas (oxygen,
carbon dioxide) and
moisture barrier
properties
excellent electrical
insulating properties
low gas
permeability, in
particularly with
carbon dioxide
approved safe for
contact with foods
and beverages
recyclable and
transparent to
microwave radiation
Does not break or
fracture
suitable for
transparent
applications
broad range of use
temperature (-60 to
130°C)

5. Physical and Material
Properties
Polyethylene Terephthalate (PET)

6. Physical Properties.
Properties Value (Unit)
Density 1.45 g 𝑐𝑚−3
Flammability Self Extinguishing
Limiting Oxygen Index 21%
Refractive Index 1.58-1.64
Resistance to Ultraviolet Ray Good
Water Absorption 0.1%

7. Material Properties
 a) Chemical Resistance  b)Thermal Properties
Properties Results
Acid Good
Alcohols Good
Alkalis Poor
Aromatic
Hydrocarbons
Fair
Oils and
Greases
Good
Halogens Good
Ketone Good
Properties Value (Units)
Coefficient of thermal
expansion ( x10-6 K-1 )
20 – 80
Specific heat ( J.K-1.kg-1 ) 1200-1350
Thermal conductivity ( W.m-
1.K-1 )
23

8. Material Properties.
 Mechanical Properties  Electrical Properties
Properties Value
(Units)
Coefficient of friction 0.2 – 0.4
Poisson’s ratio 0.37 – 0.44
Tensile modulus ( GPa ) 2 – 4
Tensile Strength 80
Properties Value (Units)
Dielectric constant @ 1
MHz
3.0
Dielectric strength (
kV.mm-1 )
17
Surface resistivity (
Ohm/sq )
1013
Dissipation factor @ 1 kHz 0.002

9. Manufacturing process
 PET bottles or containers are manufactured by using 2 different methods :
1. ‘hot-perform’ method
2. ‘cold-perform’ method

10. Hot-Perform Method

11. Cold-Perform Method

12. Drying and Dehumidifying of PET
 Since PET absorbs an average of 0.05% moisture of water, the PET need to be dried
to reduce the water so the content of water will become less or equal to 0.05% and it
also helps in increasing the quality of preform in transparency and their physical
performance.

13. Oven Dry
The drying is done at 110ºC for 8 hours after PET start to fail. The tray that was being
used to put the PET in the oven is about 50mm thick and the oven is not connected to
the injection machine. The dried PET was removed manually.
Hopper Dryer The method was being use economically since it works with an autoloader that make
the process continuous and automatic.
Dehumidifier It is most efficient drying method because PET dries temperature is around 32 °C and
the optimum drying temperature is around 150 to 170°C. PET need to dry for about 4
hours and cannot exceed 7-8 hours because it can reduce the quality of the PET.

14. Injection Moulding of The PET Preform
Schematic illustration of the injection molding process.
Source:
http://newengineeringpractice.blogspot.com/2011/08/manufac
turing-of-plastic-bottles.html?m=1

15. PET was heated and turns into molten form to inject
into injection chamber until the chamber full
when the chamber full, the screw pushed forward to fill
injection cavity with molten plastic through nozzle into
mold
- at rear machine temperature are around 275°C
-at the middle machine temperature around 282°C
-at the nozzle temperature around 280°C
- the runner temperature around 270°C
molten plastic were called preform was being cool down using
cooling water with range temperature between 15-20°C and
pressure around 500,00Pa
PET preform is ejected from mold and being reheated to the
suitable temperature for blowing process

16. Blow Moulding of PET Preform to
Container
 Process to form a hollow for an object by blowing into thermoplastic. PET
preform was heated into its maximum elastic condition and the PET will be
stretch into their desire shape for example a container.
 2 types of blow moulding
- Extrusion blow moulding
- Injection blow moulding

17. Extrusion Blow Moulding

18. Injection Blow Moulding
Illustration source:
http://newengineeringpractice.blogspot.com/2011/08/manufactur
ing-of-plastic-bottles.html?m=1

19. Local Company Produce
 Company’s name: Apple Lady
 Founded in 1987 as Jintye Trading and upgraded in 1990 as Jintye Corporation (M)
Sdn. Bhd.
 More than 1300 types of plastic ware such as bottle, food container, basin and
multipurpose container are produced.
 Prefer polyethylene terephthalate as main material to produce.
 Honoured with ISO 9001:2008.
 Follows Government environmental policy that recommends plastic ware instead
of polystyrene (EPS).
 Slogan used: ‘Making Life Better’
Source:
http://www.applelady.com.my/index.php?option=com_content&view=article&id=53&I
temid=53

20. Product Examples
(Tumbler)
Source:
http://www.applelady.com.my/index.php?option=com_phocagallery&view
=category&id=33:tumbler-collection&Itemid=136

21. References
 2020. Omnexus. Polyethelene Terephthalate. https://omnexus.specialchem.com/selection-
guide/polyethylene-terephthalate-pet-plastic
 2020. Encyclopedia Britannica. Polyethelene Terepththalate.
https://www.britannica.com/science/polyethylene-terephthalate
 AZoM. 2003. Polyethylene Terephthalate Polyester ( PET, PETP ) - Properties and Applications -
Supplier Data by Goodfellow. 25 Jun 2003. https://www.azom.com/article.aspx?ArticleID=2047
 Farazila Yusof. 2012. Physical Properties of PET. May 2012.
https://www.researchgate.net/figure/Physical-properties-of-PET-and-A5052_tbl2_236845875
 SpecialChem. Polyethylene Terephthalate (PET): A Comprehensive Review.
https://omnexus.specialchem.com/selection-guide/polyethylene-terephthalate-pet-plastic
 Firas Awaja. 2005. Physical and Chemical Properties of PET. July 2005.
https://www.researchgate.net/figure/Physical-and-chemical-properties-of-PET_tbl1_222220710
 Nd. Manufacturing of PET bottles.
 http://newengineeringpractice.blogspot.com/2011/08/manufacturing-of-plastic-bottles.html?m=1