Polyvinyl Chloride By Annalisa McClure and Catherine Carey.
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Transcript of Polyvinyl Chloride By Annalisa McClure and Catherine Carey.
Polyvinyl ChloridePolyvinyl Chloride
By Annalisa McClureBy Annalisa McClure
andand
Catherine CareyCatherine Carey
Discovery : SerendipityDiscovery : Serendipity When: 1835 – Henri Victory Regnault,When: 1835 – Henri Victory Regnault,
and again in 1872 – Eugen Baumannand again in 1872 – Eugen Baumann
Discovery : SerendipityDiscovery : Serendipity In both cases, the polymer formed itself as a In both cases, the polymer formed itself as a
white solid inside flasks of vinyl chloride white solid inside flasks of vinyl chloride exposed to sunlightexposed to sunlight
Making use of itMaking use of it - no attempt to develop a product with it till - no attempt to develop a product with it till
early the next century. –early the next century. – -- proved to be too rigid and brittle-- proved to be too rigid and brittle
The blessing and the bane:The blessing and the bane:
The blessingThe blessing: plasticizers: plasticizers 1926 -- Waldo Semon created the process 1926 -- Waldo Semon created the process
of adding them. of adding them. Plasticizers make PVC flexible and easy to Plasticizers make PVC flexible and easy to
process.process. 3 millions tons/year in 1965, 20 million 3 millions tons/year in 1965, 20 million
tons/year now.tons/year now. Pvc is one-fifth of all plasticsPvc is one-fifth of all plastics
The blessingThe blessing::Quality of lifeQuality of life
The blessing and the bane:The blessing and the bane:
The baneThe bane:: 1. Plasticizers, 1. Plasticizers,
2. Dioxin, 2. Dioxin,
3. Recyling difficulty3. Recyling difficulty
The blessing and the bane:The blessing and the bane:
The blessing and the bane:The blessing and the bane:
The baneThe bane:: 1. Plasticizers 1. Plasticizers
(phthalates) (phthalates)
They leach They leach out of the out of the plasticplastic
The baneThe bane: 1. Plasticizers (phthalates): 1. Plasticizers (phthalates) Now found globally in rain water, soil, food, and in Now found globally in rain water, soil, food, and in
humans and wildlifehumans and wildlife 90 percent of all phthalates are used in vinyl 90 percent of all phthalates are used in vinyl
productsproducts Animal studies: Damages sexual development in Animal studies: Damages sexual development in
young rats, causes liver tumorsyoung rats, causes liver tumors In humans: Impairs male reproductive system In humans: Impairs male reproductive system
development in human infants and toddlersdevelopment in human infants and toddlers
The blessing and the bane:The blessing and the bane:
The blessing and the bane:The blessing and the bane: The baneThe bane: 2. Very difficult to recycle:: 2. Very difficult to recycle: Lifespan of 30 years or more, so natural Lifespan of 30 years or more, so natural
breakdown is almost nilbreakdown is almost nil
Only 3% in EU by mechanical breakdown; Only 3% in EU by mechanical breakdown; estimated max of 9% by 2010 or 2020.estimated max of 9% by 2010 or 2020.
Pvc mixed in with other plastics makes the Pvc mixed in with other plastics makes the others more difficult to recycle.others more difficult to recycle.
The bane The bane : 3. Dioxin : 3. Dioxin
- Incineration produces carcinogenic dioxin, and - Incineration produces carcinogenic dioxin, and doesn’t decrease the volume to be disposed of.doesn’t decrease the volume to be disposed of.
The blessing and the bane:The blessing and the bane:
Chlorine in = dioxin outChlorine in = dioxin out
The blessing and the bane:The blessing and the bane:
Wonder why dioxins are formed in Wonder why dioxins are formed in incinerators? Trace the chlorine!incinerators? Trace the chlorine!
PVC-free alternatives exist!PVC-free alternatives exist!Many used in Sidney Olympics Many used in Sidney Olympics
20002000
Material Material production now production now esclating with esclating with Cargill/Dow facility Cargill/Dow facility capacity of 300 capacity of 300 million pounds per million pounds per year PLA year PLA (polylactic acid) (polylactic acid) for NatureWorks for NatureWorks fabrics and plastic.fabrics and plastic.
Biobased PlasticsBiobased Plastics
Blue Man GroupBlue Man GroupWho?Who?
What does this have to do with PVC?What does this have to do with PVC?InstrumentsInstruments
Starting materialStarting material Ethyne + HCL=PVCEthyne + HCL=PVC Polymers formed from ethylene or substituted Polymers formed from ethylene or substituted
ethylenes are called vinyl polymersethylenes are called vinyl polymers No catalyst foundNo catalyst found
Mechanism of polymerizationMechanism of polymerization– Segment of PVC containing 3 units of vinyl chloride, initiated by Segment of PVC containing 3 units of vinyl chloride, initiated by
hydrogen peroxide (Radical Initiator here)hydrogen peroxide (Radical Initiator here)– Radical polymerization (also undergoes Anionic)Radical polymerization (also undergoes Anionic)– Initiator breaks homolytically into radicalsInitiator breaks homolytically into radicals– 3 steps3 steps
initiationinitiation propagationpropagation terminationtermination
Polymer looks like this…. Polymer looks like this…. Branching vs. Unbranching Branching vs. Unbranching
Added for flexibilityAdded for flexibility Products such as raincoats, shower curtains, and Products such as raincoats, shower curtains, and
garden hosesgarden hoses ““New car smell”New car smell” Health and SafetyHealth and Safety