How laminates with EVAL EVOH film improve the performance of VIPs Cynthia Teniers EVAL Europe nv (Belgium) 17th & 18th September 2009 The Royal Institution of Great Britain, London
Established in 1926 70 companies 7000 employees Leader in high gas barrier technology and development World s leading producer of EVOH (ethylene vinyl-alcohol copolymer resins)
Our products EVAL EVOH resins EVAL EVOH films Monolayer EVOH films Vacuum metallized EVOH films
VIP value chain Insulating material Adhesives VIP EVAL EVOH films Polymer films Polymer-based metallized films Metal foil (aluminium) VIP barrier film (VIP laminate)
How laminates with EVAL EVOH film improve the performance of VIPs Cynthia Teniers EVAL Europe nv (Belgium) 17th & 18th September 2009 The Royal Institution of Great Britain, London
Recent VIP successes in Japan Courtesy of Panasonic - www.panasonic.co.jp Eco Cute from Panasonic CO 2 heat pump for hot water heater VIP around metal hot water tank (volume: 460 l or 370 l) Technical requirements Temperature (60 C/100 C) Moist conditons
Recent VIP successes in Japan Courtesy of Panasonic - www.panasonic.co.jp Floor heating VIP underneath floor heating elements Technical requirements Temperature (40 C) Long service life (20 years)
Recent VIP successes in Japan Courtesy of Panasonic - www.panasonic.co.jp Wall heating VIP underneath wall heating elements in a bathroom/toilet Technical requirements Temperature (40 C) Moist conditons Long service life (20 years)
Recent VIP successes in Japan Courtesy of Achilles Co., Ltd - www.achilles.jp Insulation boards for walls VIP integrated in a PUR-board to avoid damage during installation Technical requirements Moist conditions Long service life (50 years)
VIP market needs / trends High temperature Moist conditions Longer service life Market volumes
Technical challenges VIP laminates Minimal thermal conductivity Minimal gas permeation through the skin O 2 Resistance to manipulation Minimal gas permeation through the seals O 2
How to achieve minimal thermal conductivity? λ total = λ solid + λ gas + λ radiation + λ convection Reduced atmospheric pressure inside the VIP Almost zero Negligible below 100 C Use envelopes/films with a high gas barrier Use aluminium foil (very lowλ gas but high λ solid ) Use gas barrier film - EVAL EVOH film (lowλ gas and lowλ solid ) Reduce the thickness of the aluminium layer Use metallized films - EVAL VM-XL (lowλ solid and very lowλ gas )
Minimal thermal conductivity Average thermal conductivity (W/mK) 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 Al/Al Al/EVAL VM-XL EVAL VM-XL/EVAL VM-XL Core material VIP ½ thermal conductivity 0 1 2 3 4 5 VIP surface Use an Al/EVAL VM-XL envelope instead of an Al/Al envelope and you will increase the insulation performance of the VIP
Technical challenges VIP laminates Minimal thermal conductivity Minimal gas permeation through the skin O 2 Resistance to manipulation Minimal gas permeation through the seals O 2
Resistance to manipulation Gelbo flex test
Resistance to manipulation Oxygen transmission rate (20 C,65% RH) after Gelbo flex test OTR (cc/m².day.atm) 12 10 8 6 4 2 0 0 20 40 60 80 100 Number of flex times EVAL EF-XL 12 µm EVAL VM-XL 12 µm VM-PET 12 µm Al 2 O 3 -PET 12 µm SiO x -PET 12 µm PVDC coated PET 22 µm Use EVAL EVOH films to ensure that the barrier of the VIP is not damaged during production, transport and installation
Technical challenges VIP laminates Minimal thermal conductivity Minimal gas permeation through the skin O 2 Resistance to manipulation Minimal gas permeation through the seals O 2
Minimal gas permeation through the skin OTR (cc/m².day.atm) WVTR (g/m².day) 0.01 0.05 0.05 40 C, 65% RH 40 C, 65% RH 0.5 0.1 40 C, 90% RH EVAL TM-XL New generation of vacuum metallized EVOH film For applications with higher operating temperatures, moist conditions and a longer service life A robust film with excellent oxygen barrier and improved water vapour barrier EVAL TM-XL EVAL VM-XL
Technical challenges VIP laminates Minimal thermal conductivity Minimal gas permeation through the skin O 2 Resistance to manipulation Minimal gas permeation through the seals O 2
Minimal gas permeation through seals Films Oxygen transmission rates of selected polymers (cc.20 µm/m².d.atm) 20 C, 65% RH 20 C, 85% RH EVAL EF-XL 0.38 0.75 EVAL EF-F 0.40 1.6 EVAL EF-E 1.6 3.4 x 2030 x 950 cpp 3250 3250 LDPE 10000 x 6250 10000 x 2940 Use EVAL EVOH films to reduce the total permeation of oxygen via the seals and extend the life time of the VIPs
Minimal gas permeation through seals 3 Seal Strength (kg/15 mm) 2.5 2 1.5 1 0.5 0 150 155 160 165 170 Sealing temperature ( C) EVAL EF-E 30 micron EVAL EF-E 25 micron Seal conditions: force = 1kg/cm 2, dwell time = 0.5 seconds Laminate structure: OPA//EVAL EF-E Typical sealing temperatures for EVAL EVOH films
Conclusion EVAL EVOH films can be introduced as an intermediate layer and/or sealing layer EVAL EVOH film EVAL EVOH film Intermediate layer Sealing layer
Conclusion Use EVAL EVOH films to increase the insulation performance, service life and operating temperature of VIPs Minimal thermal conductivity Minimal gas permeation through the skin O 2 Resistance to manipulation Minimal gas permeation through the seals O 2