This paper describes and evaluates accelerated aging of a titanium dioxide (TiO2) filled polyamide (PA) based backsheet film for photovoltaic (PV) modules. Damp heat exposure (85%RH, 85 °C) was carried out up to 2000 hrs. The backsheet was characterized using microscopic, spectroscopic, thermoanalytic, chromatographic, and mechanical methods. While Raman microscopy, infrared spectroscopy in attenuated total reflection mode (IR-ATR), scanning calorimetry (DSC), and thermal gravimetric analysis did not reveal aging-induced changes, significant yellowing was detected by ultraviolet visible near infrared (UV/VIS/NIR) spectroscopy. Depending on the stabilizer type (UV-absorbers, hindered amine light stabilizers (HALSs), and antioxidants), rather different consumption rates were ascertained by high-performance liquid chromatography (HPLC) and gas chromatography (GC). Although the ultimate mechanical properties decreased significantly, no full embrittlement was obtained after damp heat exposure of up to 2000 hrs. The observed physical and chemical aging mechanisms were classified as within the induction period without premature failure.

References

References
1.
Oreski
,
G.
, and
Wallner
,
G. M.
,
2005
, “
Aging Mechanisms of Polymeric Films for PV Encapsulation
,”
Sol. Energy
,
79
(
6
), pp.
612
617
.
2.
Roekens
,
H.
, and
Beyer
,
A.
,
2007
, “
Big Opportunity for the Plastics Industry
,”
Kunststoffe International
, pp.
54
57
.
3.
Richard
,
D.
,
2010
,
EVA and Tedlar Still Dominate: Market Survey on Encapsulation Materials
,
Photon International
, Aachen, Germany, pp.
236
259
.
4.
Richard
,
D.
,
2011
,
The Right Chemistry: Market Survey on Encapsulation Materials Sees a New Trend, With Companies Moving Toward Alternatives to Tedlar, While EVA Still Holds Its Ground
,
Photon International
, Aachen, Germany, pp.
280
302
.
5.
Poliskie
,
M.
, ed.,
2011
,
Solar Module Packaging
,
CRC Press
, Boca Raton, FL.
6.
Mikats
,
G.
,
2011
, “
Solar Module and Coextrudate Element
,” Patent No. CA2782097 A1.
7.
Geretschläger
,
K. J.
,
Wallner
,
G. M.
, and
Fischer
,
J.
, “
Structure and Basic Properties of Photovoltaic Module Backsheet Films
,”
Sol. Energy Mater. Sol. Cells
144
, pp.
451
456
..
8.
Verleye
,
G. A. L.
,
Roeges
,
N. P. G.
, and
De Moor
,
M. O.
,
2001
,
Easy Identification of Plastics and Rubbers
,
Rapra Technology
,
Shrewsbury, UK
.
9.
Dong
,
W.
, and
Gijsman
,
P.
,
2010
, “
Influence of Temperature on the Thermo-Oxidative Degradation of Polyamide 6 Films
,”
Polym. Degrad. Stab.
,
95
(
6
), pp.
1054
1062
.
10.
Hintersteiner
,
I.
,
Sternbauer
,
L.
,
Beissmann
,
S.
,
Buchberger
,
W. W.
, and
Wallner
,
G. M.
,
2014
, “
Determination of Stabilisers in Polymeric Materials Used as Encapsulants in Photovoltaic Modules
,”
Polym. Test.
,
33
, pp.
172
178
.
11.
Bird
,
R. E.
,
Hulstrom
,
R. L.
, and
Lewis
,
L. J.
,
1983
, “
Terrestrial Solar Spectral Data Sets
,”
Sol. Energy
,
30
(
6
), pp.
563
573
.
12.
Wallner
,
G. M.
,
Platzer
,
W.
, and
Lang
,
R. W.
,
2005
, “
Structure–Property Correlations of Polymeric Films for Transparent Insulation Wall Applications—Part 1: Solar Optical Properties
,”
Sol. Energy
,
79
(
6
), pp.
583
592
.
13.
ASTM
,
1988
, “
Standard Test Method for Yellowness Index of Plastics
,” D-20 Committee, ASTM International, West Conshohocken, PA, Standard No. ASTM D 1925-70.
14.
ASTM
, 1998, “
Standard Practice for Calculating Yellowness and Whiteness Indices From Instrumentally Measured Color Coordinates
,” E-12 Committee, ASTM International, West Conshohocken, PA, Standard No. ASTM E 313-98.
15.
Kang
,
B.
,
Moon
,
O.
,
Hong
,
C.
,
Lee
,
H.
,
Cho
,
B.
, and
Kim
,
Y.
,
2002
, “
Design of Advanced Color-Temperature Control System for HDTV Applications
,”
J. Korean Phys. Soc.
,
41
, pp.
865
871
.
16.
Shevell
,
S. K.
,
2003
,
The Science of Color
,
2nd ed.
,
Elsevier/Optical Society of America
,
Amsterdam, The Netherlands/Boston, MA
.
17.
DIN Deutsches Institut für Normung e.V.
,
2004
,
Mechanische und thermische Eigenschaften
,
Prüfnormen
,
Beuth, Berlin
.
18.
Celina
,
M.
,
Ottesen
,
D. K.
,
Gillen
,
K. T.
, and
Clough
,
R. L.
,
1997
, “
FTIR Emission Spectroscopy Applied to Polymer Degradation
,”
Polym. Degrad. Stab.
,
58
, pp.
15
31
.
19.
El-Mazry
,
C.
,
Ben Hassine
,
M.
,
Correc
,
O.
, and
Colin
,
X.
,
2013
, “
Thermal Oxidation Kinetics of Additive Free Polyamide 6-6
,”
Polym. Degrad. Stab.
,
98
(
1
), pp.
22
36
.
20.
Gonçalves
,
E. S.
,
Poulsen
,
L.
, and
Ogilby
,
P. R.
,
2007
, “
Mechanism of the Temperature-Dependent Degradation of Polyamide 66 Films Exposed to Water
,”
Polym. Degrad. Stab.
,
92
(
11
), pp.
1977
1985
.
21.
Frick
,
A.
, and
Stern
,
C.
,
2004
, “
Qualitätssicherung von Kunststoffformteilen mittels DSC Teil 2: Fertigungskontrolle
,”
UserCom
,
2
, pp.
9
12
.
22.
Hässler
,
R.
, and
Kunze
,
W.
,
2007
,
Thermische Eigenschaften polymerer Werkstoffe: DMA-DSC-TGA-TMA-μTA; Stoffsammlung thermoanalytischer Messungen
,
1st ed.
,
TA-Instruments
,
Eschborn, Germany
.
23.
Ehrenstein
,
G. W.
,
Riedel
,
G.
, and
Trawiel
,
P.
,
1998
,
Praxis der thermischen Analyse von Kunststoffen
,
Hanser
,
München, Germany
.
24.
ADEKA Corporation
, “
ADK STAB Plastics Additives: Products List. ADK STAB Catalogue
.”
25.
BASF
, “
Additives for Specialty Polymers: Plastic Additives. Additives for Specialty Polymers
.”
26.
BASF
, “
Technical Information Plastic Additives: Tinuvin 770 Low Molecular Weight Hindered Amine Light Stabilizer (HALS)
.”
27.
BASF
, “
Technical Information Plastic Additives: Tinuvin 234 Low Volatile Benzotriazole UV Absorber
.”
28.
BASF
, “
Technical Information Plastic Additives: Irganox 1010 Phenolic Primary Antioxidant for Processing and Long-Term Thermal Stabilization
.”
29.
Beer
,
S.
,
Teasdale
,
I.
, and
Brueggemann
,
O.
,
2013
, “
Immobilization of Antioxidants Via ADMET Polymerization for Enhanced Long-Term Stabilization of Polyolefins
,”
Eur. Polym. J.
,
49
(
12
), pp.
4257
4264
.
30.
Beißmann
,
S.
,
Stiftinger
,
M.
,
Grabmayer
,
K.
,
Wallner
,
G.
,
Nitsche
,
D.
, and
Buchberger
,
W.
,
2013
, “
Monitoring the Degradation of Stabilization Systems in Polypropylene During Accelerated Aging Tests by Liquid Chromatography Combined With Atmospheric Pressure Chemical Ionization Mass Spectrometry
,”
Polym. Degrad. Stab.
,
98
(
9
), pp.
1655
1661
.
31.
BASF
, “
Technical Information Plastic Additives: Irganox 1098 Phenolic Primary Antioxidant for Processing and Long-Term Thermal Stabilization
.”
You do not currently have access to this content.