Over time, these additives leach out of vinyl products. Phthalates are typically present in indoor air at much higher concentrations than outdoor air due to their high concentrations in consumer products and building materials.
PolyVinyl Chloride (PVC) LAM Kwok Tung Kenny(52610985) Ngai Sau Man Carmen (52621860) Lee Wing Man (52569943) Chow Lai Yin Kevin (52621822)
Plastic Molecular unit (Carbon, Hydrogen) repeated and formed chains Man-made “first plastic” :celluloid In1860s’ To replace Ivory
Types of plastic Resin identification code Lots of types of plastic Different molecular unit Different chemical and physical feature♵ PVC
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
PolyVinyl Chloride (PVC) Cheap Easy to produce Wildly used Add Plasticizer to change its hardness Plastic Wrap, tube…
PVC Production In HongKong Sunny Hose Company Limited In Tai Po Produce Tubes For water supply or sprinkle
Processes Cracking and Polymerizatio Molding Chlorination n VCM(Vinyl PVC(PolyvPetroleum chloride inyl Products monomer) chloride)
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
Polymerization of PVC Condition : UV light or heat and pressure Organic peroxide compounds(initiator) Monomer(VCM) Addition polymerization Free radical addition
Environment & human Wholeproduct life cycle: production use disposalProduction: Releases of EDC and VCM carcinogensduring process; Release of heavy distillate material
Use: Release of toxicants in PVC productsDisposal: landfill cause leachates incinerated generate dioxin
Productionvinyl chloride monomer (VCM) & ethylene dichloride (EDC) are by-products of PVCOn human: highly volatile VCM jeopardise workers’ health ( risk of liver / brain cancer) colourless EDC , inhalation/ direct contact may have toxic effect
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
Use the use of PVC products threaten human healthOn 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
Disposal discarded PVC materials are hazardousOn 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
On environment: burning of chloride (major component of PVC) during combustion of incinerationRelease of toxic dioxin regarded as persistent organic pollutants (POPs), dioxin accumulate in atmosphere recycling of PVC is extremely difficult
A particular slide catching your eye?
Clipping is a handy way to collect important slides you want to go back to later.