Technical Meeting

1
Technical Meeting STFI -State WP2 Nonwoven
textiles for top layer and top coating
2
1. Backside of top layer

• Existing Problem
• The hotmelt (EVA copolymer) used until now is not
  suitable for lamination onto the basic layer
  since the adhesion between the layers is
  insufficient, the high temperatures of bitumen
  destroy the hotmelt layer and resistance to oil
  is not given (yellow staining).
• Improvement could bring a change of the hotmelt
  agent used for back coating and/or a mechanical
  treatment (for instance roughening) to produce a
  structured surface.
• Further improvement might be possible if another
  nonwoven as barrier layer is used.
• ? Technical Meeting on 4 August 2011 between STFI
  and Borner at STFI

3
Activities/Trials

• B1 Using a second layer of nonwoven as barrier
  layer
• At the backside of the top layer a second layer
  of nonwovens should be applied by lamination
  (composite structure).
• Disadvantage increased costs due to the second
  layer and a further processing step to build up
  the composite (lamination)
• A sample selection of spunbonded nonwovens was
  handed over to Gerhard during the technical
  meeting.
• Tests on adhesion properties with Bitumen were
  done by Borner.
• Results of tests concerning adhesion of the
  nonwovens done by Borner Sample 1 (PET/PA
  7822 55 gr/m²)
• peel resistance 36 N/5 cm mean, 92 N/5 cm peak
  beginning adhesive failure fleece/bitumen at peak
  value, followed by cohesive failure within the
  fleece
• Sample 2 (PET/PA 7030 60 gr/m²)
• peel resistance 115 N/5 cm mean, 125 N/5 cm peak
  mixed cohesive failure bitumen / adhesive failure
  fleece/bitumen followed by rupture of the fleece.
  The favorite!!
• Sample 3 (PET)
• peel resistance 46 N/5 cm mean, 83 N/5 cm peak
  mixed failure rupture of the fleece and adhesive
  failure fleece/bitumen were observed

4
Activities/Trials

• B2 Using another hotmelt adhesive - PUR
• The top layer nonwoven (NRVII - PA 35 g/m²) was
  coated with PUR hotmelt and mechanically roughed
  to change the surface structure and improve the
  adhesion.
• The material was sent to Borner by mid of August
  for testing the adhesion, the processability with
  bitumen and the resistance against staining.
• Results of tests concerning adhesion and stain
  resistance done by Borner
• Unaged material adhesive failure film/bitumen
  (83 N/5cm mean /
• 108 N/5 cm peak) ? Values more than 4 times
  better compared to EVA
• After thermal ageing still under progress some
  yellowing occured up to now, but no oil
  penetration observed. No shrinkage
• Cold flexibility still to be tested

5
Activities/Trials

• B3 Using another hotmelt adhesive - PVB
• Borner proposed to use another hotmelt agent for
  back coating named PVB (Polyvinylbutyral). PVB
  was sent to STFI where some trials were done. PVB
  is not suitable for processing at hotmelt unit
  since the Melt Flow Index (MFI) is too low, but
  it can be processed with STFIs flat bed
  lamination plant.
• The trials were done at different working speeds.
  The material was sent to Borner at beginning of
  September for testing.
• Coating tests with NANOPHOS paint has to follow.
• Results of tests concerning adhesion and stain
  resistance done by Borner
• Unaged material, lamination speed 5 m/min
• Peel resistance 122 N/5 cm mean, 155 N/5 cm peak,
  cohesive failure bitumen, followed by rupture of
  the film/fleece compound. Values more than 6
  times better compared to EVA ? Best values seen
  up to now!!
• After thermal ageing still under progress no
  yellowing, no shrinkage observed up to now
• Cold flexibility still to be tested
• Water permeability testing is still under
  progress (STFI)

6
Activities/Trials

• B4 Improve the properties of EVA hotmelt by
  Arginotec
• Discussion with NOTT and Borner by end of August
  proposal is to include Arginotec (10) into the
  EVA hotmelt (first hotmelt variant) to achieve
  good hydrophobicity and a good oil resistance.
• NOTT knows a manufacturer who is able to produce
  a masterbatch of hotmelt EVA and Arginotec.
• The masterbatch will be sent to STFI for further
  hotmelt trials by mid of September.
• Borner will do tests on oil resistance after
  hotmelt trials.
• Disadvantage When EVA hotmelt is used than a
  second nonwoven layer for better adhesion is
  required (see B1) ? increased costs due to
  composite structure

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2. Top layer coating

• NANOPHOS sent the following paint samples to
  STFI
• SurfaPaint with higher viscosity
• SurfaPaint with 5 Arginotec
• PU acrylic modified resin with 10 Arginotec
  (primer)
• STFI did different paint trials and produced some
  hand samples in different variants (see next
  slides).
• The variants differ concerning the
• surface (with or without Encryl)
• the top coating (with or without primer, number
  of paint layers)
• the backside (EVA or PUR)

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2. Top layer coating

• Top layer material used for all coating trials
  NRVII
• 100 Polyamid (PA), spunbond nonwoven
  (thermobonded)
• Mass per unit area 35 g/m²
• ? Samples were sent to TNO for reflectance tests
  and to TNO for
• testing the thermal behaviour ? any
  results??
• Variant 1 (V1.6 -1.10)

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2. Top layer coating
Variant 2 (V2.1 -2.5)
Variant 3 (V3.1 -3.6)
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2. Top layer coating
Variant 4 (4.1 4.5)
Variant 5 (5.1 5.7)
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Next decisions
to be found to continue with material
production for weathering and application tests

• Backside
• selection of best variant of backside coating
• EVA with barrier layer
• PUR
• PVB
• 2. Top coating
• Following the reflectance and thermal behaviour
  tests ? selection of the
• most suitable coating variant
• with or without primer??
• two layers of surfapaint with Arginotec??
• one layer of surfapaint with Arginotec??