1. PolyVinyl Chloride (PVC)
LAM Kwok Tung Kenny(52610985)
Ngai Sau Man Carmen (52621860)
Lee Wing Man (52569943)
Chow Lai Yin Kevin (52621822)

2. INTRODUCTION

3. Plastic
 Molecular unit (Carbon, Hydrogen)
 repeated and formed chains
 Man-made
 “first plastic” :celluloid
 In1860s’
 To replace Ivory

4. Types of plastic
 Resin identification code
 Lots of types of plastic
 Different molecular unit
 Different chemical and physical
feature
♵
 PVC

5. PolyVinyl Chloride (PVC)
 Molecular unit 
 Light and High Toughness
 Colorless
 Not easy to be corrode
by acid or base
 Fire Retardant
 Add Plasticizer to change its hardness
 Vicat softening point : 65- 100

6. PolyVinyl Chloride (PVC)
 Cheap
 Easy to produce
 Wildly used
 Add Plasticizer to change its
hardness
 Plastic Wrap, tube…

7. PVC Production In Hong
Kong
 Sunny Hose Company Limited
 In Tai Po
 Produce Tubes
 For water supply or sprinkle

8. MANUFACTURING
PVC(POLYVINYL
CHLORIDE) PRODUCT

9. Processes
Cracking and Polymerizatio
Molding
Chlorination n
VCM(Vinyl PVC(Polyv
Petroleum chloride inyl Products
monomer) chloride)

10. Cracking and Chlorination
 Petroleum heated with catalyst, high
pressure and without air
 Produce Ethene and “light”
hydrocarbons
 Chlorination to ethene
 Thermal cracking
 Chloroethene
 Vinyl chloride monomer

11. Polymerization of PVC
 Condition : UV light or heat and
pressure
 Organic peroxide compounds(initiator)
 Monomer(VCM)
 Addition polymerization
 Free radical addition

12. Mechanism
 Chain initiation :
 Chain propagation :
 Chain termination :

13. Polymerization of PVC
 Molecule masses vary with the
temperature
 Exothermic reaction
 Strong intermolecular force
 Dipole-dipole between
polymer chains

14. Adding additive
 Plasticizer(塑化劑)
 DEHP(di-2-ethyl hexyl phthalate)
 Filler
 Stabilizer
 Dyes or coloring
C6H4(C8H17COO)2
Bis(2-
ethylhexyl)phthalate(BEHP)

15. Molding
 Using heat to soft the plastic, pressure
to squeeze and place to a mold, then
cool down
 Injection molding(a)
 Compression molding(b)
a b

16. Beyond your imagination !!!
DANGER OF PVC

17. Environment & human
 Wholeproduct life cycle:
production use  disposal
Production:
 Releases of EDC and VCM carcinogens
during process;
 Release of heavy distillate material

18. Use:
 Release of toxicants in PVC products
Disposal:
 landfill cause leachates
 incinerated generate dioxin

19. Production
vinyl chloride monomer
(VCM) & ethylene dichloride
(EDC) are by-products of PVC
On human:
 highly volatile VCM jeopardise workers’ health
( risk of liver / brain cancer)
 colourless EDC , inhalation/ direct contact may
have toxic effect

20.  VCM & EDC are genotoxic
 cause irreversible damage to DNA
(e.g. Birth defects/ genetic diseases of
descendants)
On environment:
 improper treatment of VCM & EDC or
other by-products contaminate
(underground)water and sediment (e.g.
alluvial soil)
Case study:
In Japan, consumption on rice irrigated by

21. Use
 the use of PVC products threaten
human health
On human:
 PVC additives phthalate plasticizers
increase risk of asthma
 PVC flooring  persistent wheezing,
pneumonia, prolonged cough… etc
 metal stabilizers (e.g. lead) leach into
potable water

22. Disposal
 discarded PVC materials are hazardous
On human:
 phthalates and metals leach out of
disposed products into landfill leachate
groundwater contamination
 accidental PVC fire  permanent
respiratory disease
 fire release dioxin  reproductive
disorders, immune suppression

23. On environment:
 burning of chloride (major component
of PVC) during combustion of
incineration
Release of toxic dioxin
 regarded as persistent organic
pollutants (POPs), dioxin accumulate
in atmosphere
 recycling of PVC is extremely difficult