PMID- 38005001
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20231127
IS  - 1996-1944 (Print)
IS  - 1996-1944 (Electronic)
IS  - 1996-1944 (Linking)
VI  - 16
IP  - 22
DP  - 2023 Nov 7
TI  - Influence of Long-Term Storage and UV Light Exposure on Characteristics of 
      Polyurethane Foams for Cryogenic Insulation.
LID - 10.3390/ma16227071 [doi]
LID - 7071
AB  - Rigid polyurethane (PUR) foams have been the most effective insulation material 
      used in space launchers since the beginning of cryogenic fuel use, due to their 
      outstanding thermal and mechanical properties. In this study, spray-applied PUR 
      foams using different ratios of amine-based catalysts were produced. Due to 
      climate change, several restrictions have been made regarding the usage of 
      blowing agents used for PUR foam production. Lately, hydrofluoroolefins (HFOs) 
      have been suggested as an alternative for PUR foam production due to their low 
      global warming potential (GWP) and ozone depletion potential (ODP), replacing the 
      hydrofluorocarbons (HFCs) so far used. This change in blowing agents naturally 
      altered the usage of catalysts. Reactive amine-based catalysts are less hazardous 
      because of their low volatility and ability to react successfully with isocyanate 
      or polyols. Spray-applied PUR foams with a potential application for cryogenic 
      insulation were produced and tested for long-term storage, analyzing parameters 
      such as the pH value of polyol composition, foaming kinetics (t(rise), t(cream)), 
      etc. Athermal analysis (TG, DSC) was also applied to developed materials, as well 
      as artificial ageing by exposing samples to UV light. It was discovered that PUR 
      foams obtained using reactive amine-based catalysts, such as Polycat 203 and 218, 
      have a higher integral heat capacity, but polyol mixtures containing these 
      catalysts cannot exceed a storage time of more than 4 months. It was also 
      observed from artificial ageing tests of PUR cryogenic insulation by exposure to 
      UV light that the thickness of the degraded layer reached 0.8 mm (after 1000 h), 
      but no significant destruction of cellular structure deeper in the material was 
      observed.
FAU - Sture, Beatrise
AU  - Sture B
AD  - Polymer Laboratory, Latvian State Institute of Wood Chemistry, Dzerbenes Street 
      27, LV-1006 Riga, Latvia.
FAU - Yakushin, Vladimir
AU  - Yakushin V
AD  - Polymer Laboratory, Latvian State Institute of Wood Chemistry, Dzerbenes Street 
      27, LV-1006 Riga, Latvia.
FAU - Vevere, Laima
AU  - Vevere L
AUID- ORCID: 0000-0002-4640-5121
AD  - Polymer Laboratory, Latvian State Institute of Wood Chemistry, Dzerbenes Street 
      27, LV-1006 Riga, Latvia.
FAU - Cabulis, Ugis
AU  - Cabulis U
AUID- ORCID: 0000-0001-9465-466X
AD  - Polymer Laboratory, Latvian State Institute of Wood Chemistry, Dzerbenes Street 
      27, LV-1006 Riga, Latvia.
LA  - eng
GR  - VPP-EM-FOTONIKA-2022/1-0001/Latvian Council of Science/
PT  - Journal Article
DEP - 20231107
PL  - Switzerland
TA  - Materials (Basel)
JT  - Materials (Basel, Switzerland)
JID - 101555929
PMC - PMC10672591
OTO - NOTNLM
OT  - artificial ageing
OT  - cryogenic insulation
OT  - photodegradation
OT  - rigid polyurethane foams
COIS- The authors declare no conflict of interest. The funders had no role in the 
      design of the study; in the collection, analyses, or interpretation of data; in 
      the writing of the manuscript; or in the decision to publish the results.
EDAT- 2023/11/25 12:45
MHDA- 2023/11/25 12:46
PMCR- 2023/11/07
CRDT- 2023/11/25 01:25
PHST- 2023/09/20 00:00 [received]
PHST- 2023/10/27 00:00 [revised]
PHST- 2023/11/04 00:00 [accepted]
PHST- 2023/11/25 12:46 [medline]
PHST- 2023/11/25 12:45 [pubmed]
PHST- 2023/11/25 01:25 [entrez]
PHST- 2023/11/07 00:00 [pmc-release]
AID - ma16227071 [pii]
AID - materials-16-07071 [pii]
AID - 10.3390/ma16227071 [doi]
PST - epublish
SO  - Materials (Basel). 2023 Nov 7;16(22):7071. doi: 10.3390/ma16227071.