PVC : the long term building material

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PVC the long term building material

• Joël Fumire
• Research Technology SBU Vinyls

São Paulo, 2005
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PVC in building

• PVC is one of the most used plastics in building
• Why ?

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PVC in building

• Building means
• Strength , see the rigidity modulus !
• weather resistance in all climates
• well adapted to specific use (e.g. pipes)
• Durability from 30 to gt 100 years
• competitive cost !
• recyclable

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Comparison E Modulus
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Rigidity in Sewage

• Key property annular stiffness.
• Directly related to the E-modulus of the material
  Stiffness SN K. E. I / D3

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Good Weathering resistance

• UV-resistance
• PVC can be formulated easily to be used on a long
  term basis in very sunny climates

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PVC adapted for use drinking water pipes

• Key properties
• Pressure resistance
• No modification of the water quality
• Long term durability

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PVC adapted for drinking water pipes
Key property long term pressure resistance
PVC-U
PE100
50 y.
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PVC adapted for drinking water pipes

• No modification of water quality
• No significant leaching of substances to the
  water
• No taste or smell transferred to water
• PVC pipes comply with the requests of drinking
  water contact in the most severe regulations
  (CEE, NSF, BGVV, etc)
• Excellent resistance to bacteria growth
• PVC is approved for drinking water transportation
  in the majority of countries

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Other key properties for PVC pipes

• Chemical inertia towards many chemicals
• Cleaning liquids, acids,
• No sensitivity towards oxidising substances
• Good Fire resistance
• Among plastics, PVC is one of the most difficult
  to ignite.
• It is self-extinguishing

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Durability

• PVC pressure pipes are in use since more than 60
  years
• PVC pressure pipes are designed theoretically for
  50 years but can last more than 100 years
• PVC Window profiles are used since more than 40
  years and are still performing well

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Pressure pipes 60 years old Dr Nowack study

• Study realised in Germany published in KRV
  (1995) by Dr. Nowack
• PVC pipes were produced and installed in
  Bitterfeld in 1935-1940 with the technology
  available at that moment (physical, chemical)
• Pipes from 1938 extracted from Bitterfeld

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Pressure pipes 60 years old Dr Nowack study

• Tests on these pipes show that
• Burst-pressure curve is still linear with no
  "knee"
• Burst-pressure at 60C is found still gt 5 N/mm²
  after 600 h
• Some of the pipes are still operating today at
  20C under 5.0 bar with satisfactory performance

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TNO study on residual lifetime of PVC pipes

• Are 50 years old pipes to be replaced ?
• Study was realised between 2002 and 2005 by the
  Dutch institute TNO Science and Industry (A.
  Boersma J. Breen)
• Water pipes from the 1950's until today were
  excavated and extensively tested

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TNO study on residual lifetime of PVC pipes

• Physico-chemical analysis
• The K values were close to 66 (1 exception at
  72)
• The level of gelation was between 38 and 80
  (the pipes from the 1970's showed the lowest
  gelation)
• Analysis of the transformation of the stabiliser
  system indicates negligible consumption (at room
  temperature)

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TNO study on residual lifetime of PVC pipes

• Mechanical testing
• Craze initiation is affected by the physical
  ageing and by fatigue phenomenon
• Burst pressures are still at a good level (and
  still compliant to ISO standard)

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TNO study on residual lifetime of PVC pipes

• Main conclusions of this study are
• No chemical degradation appears
• Gelation seems to be correlated with craze
  initiation
• Fatigue could lead to an increased mechanical
  ageing
• Production and laying conditions induce
  additional stresses in the material
• The lifetime can be expected to be 100 years or
  more for high quality produced and installed
  pipes.

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Window frames since the 1970's

• Window frames are installed since the 1960's
• This window was installed in Germany in1972
• and is still in operation after more than 30
  years of good operation!
• Usually PVC frames are not replaced because of
  damage

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Competitive price costs of piping systems
(installation and assembling)
Steel
Cast Iron
Cast Iron
PE
Steel
Cast Iron
PVC-U
Steel
PE
PVC-U
PE
PVC-U
Source DVGW 1998
DN 100
DN 200
DN 150
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Recycling

• Today in Europe gt 7 000 t/y of PVC is recycled in
  pipes
• For homogeneous rigid PVC, recycling is mainly a
  collecting process
• For composite material (or heavily contaminated
  PVC) a special separation process has been
  developped

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Recycling

• PVC material can be extruded several times
• The problem is the availability of recycled
  material since the articles installed in the
  1970's are not available for recycling !

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Thank you for your attention !