Transcript C -- C - North Seattle College

Polyvinyl Chloride
 By Annalisa McClure
and
 Catherine Carey
Discovery : Serendipity
 When: 1835 – Henri Victory Regnault,
 and again in 1872 – Eugen Baumann
Discovery : Serendipity
 In both cases, the polymer formed itself as a
white solid inside flasks of vinyl chloride
exposed to sunlight
Making use of it
 - no attempt to develop a product with it till
early the next century. –
 -- proved to be too rigid and brittle
The blessing and the bane:
 The blessing: plasticizers
 1926 -- Waldo Semon created the process
of adding them.
 Plasticizers make PVC flexible and easy to
process.
 3 millions tons/year in 1965, 20 million
tons/year now.
 Pvc is one-fifth of all plastics
The blessing and the bane:
The blessing:
Quality of life
The blessing and the bane:
 The bane:
 1. Plasticizers,
 2. Dioxin,
 3. Recyling difficulty
The blessing and the bane:
 The bane:
 1. Plasticizers
(phthalates)
 They leach
out of the
plastic
The blessing and the bane:
 The bane: 1. Plasticizers
(phthalates)
 Now found globally in rain water, soil, food, and in
humans and wildlife
 90 percent of all phthalates are used in vinyl
products
 Animal studies: Damages sexual development in
young rats, causes liver tumors
 In humans: Impairs male reproductive system
development in human infants and toddlers
The blessing and the bane:
 The bane: 2. Very difficult to recycle:
 Lifespan of 30 years or more, so natural
breakdown is almost nil
 Only 3% in EU by mechanical breakdown;
estimated max of 9% by 2010 or 2020.
 Pvc mixed in with other plastics makes the
others more difficult to recycle.
The blessing and the bane:
 The bane : 3. Dioxin
 - Incineration produces carcinogenic dioxin, and
doesn’t decrease the volume to be disposed of.
The blessing and the bane:
Wonder why dioxins are formed in
incinerators? Trace the chlorine!
Chlorine in = dioxin out
PVC-free alternatives exist!
Many used in Sidney Olympics
2000
PVC-free business initiatives
Wavin: No. 1 PVC pipe producer in Europe
Biobased Plastics
 Material
production now
esclating with
Cargill/Dow
facility capacity
of 300 million
pounds per year
PLA (polylactic
acid) for
NatureWorks
fabrics and
plastic.
Blue Man Group
Who?
What does this have to do with PVC?
Instruments
 Starting material
 Ethyne + HCL=PVC
 Polymers formed from ethylene or substituted
ethylenes are called vinyl polymers
 No catalyst found

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MONOMER,
REPEATING UNIT,
NAME,
USES
 Mechanism of polymerization
– Segment of PVC containing 3 units of vinyl chloride, initiated by
hydrogen peroxide (Radical Initiator here)
– Radical polymerization (also undergoes Anionic)
– Initiator breaks homolytically into radicals
– 3 steps
 initiation
 propagation
 termination
 Polymer looks like this….
 Branching vs. Unbranching
 Added for flexibility
 Products such as raincoats, shower curtains, and
garden hoses
 “New car smell”
 Health and Safety
THE END