PMID- 30925735
OWN - NLM
STAT- MEDLINE
DCOM- 20190808
LR  - 20190808
IS  - 1420-3049 (Electronic)
IS  - 1420-3049 (Linking)
VI  - 24
IP  - 7
DP  - 2019 Mar 28
TI  - Recycled Polyethylene/Paraffin Wax/Expanded Graphite Based Heat Absorbers for 
      Thermal Energy Storage: An Artificial Aging Study.
LID - 10.3390/molecules24071217 [doi]
LID - 1217
AB  - An artificial aging study of novel heat absorbers based on phase change materials 
      (PCMs) prepared from recycled high-density polyethylene (HDPE), paraffin wax 
      (PW), and expanded graphite (EG) was investigated. The optimal composition of 
      PCMs contained 40 wt% HDPE, whereas the paraffin wax content ranged from 40 to 60 
      wt% and the expanded graphite content ranged from 5 to 15 wt%. PCMs were 
      artificially aged through exposure to UV irradiation, enhanced temperature, and 
      humidity. It was clearly demonstrated that the addition of EG to PCMs led to the 
      suppression of PW leakage and improved the photooxidation stability of the PCMs 
      during the aging process. The best performance was achieved by adding 15 wt% of 
      EG to the PCMs. The sample shows a leakage of paraffin wax below 10%, retaining a 
      melting enthalpy of PW within PCMs of 54.8 J/g, a thermal conductivity of 1.64 
      W/mK and the lowest photooxidation, characterized by an increase in the 
      concentration of carbonyl groups from all investigated materials after artificial 
      aging. Furthermore, PCMs mixed with EG exhibited good mechanical properties, even 
      after 100 days of exposure to artificial aging. Finally, this work demonstrates a 
      justification for the use of recycled plastics in the formation of PCMs.
FAU - Abdelrazeq, Haneen
AU  - Abdelrazeq H
AD  - Department of Chemical Engineering, Qatar University, P.O. Box 2713, Doha, Qatar. 
      ha082881@student.qu.edu.qa.
FAU - Sobolciak, Patrik
AU  - Sobolciak P
AD  - Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar. 
      patrik@qu.edu.qa.
FAU - Al-Ali Al-Maadeed, Mariam
AU  - Al-Ali Al-Maadeed M
AD  - Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar. 
      m.alali@qu.edu.qa.
FAU - Ouederni, Mabrouk
AU  - Ouederni M
AD  - Qatar Petrochemical Company (QAPCO), Doha 756, Qatar. m.ouederni@qapco.com.qa.
FAU - Krupa, Igor
AU  - Krupa I
AD  - QAPCO Polymer Chair, Center for Advanced Materials, Qatar University, P.O. Box 
      2713, Doha, Qatar. igor.krupa@qu.edu.qa.
LA  - eng
GR  - NPRP grant No: 4 - 465 - 2 - 173/Qatar National Research Fund/
PT  - Journal Article
DEP - 20190328
PL  - Switzerland
TA  - Molecules
JT  - Molecules (Basel, Switzerland)
JID - 100964009
RN  - 0 (Waxes)
RN  - 7782-42-5 (Graphite)
RN  - 8002-74-2 (Paraffin)
RN  - 9002-88-4 (Polyethylene)
MH  - Calorimetry, Differential Scanning
MH  - Graphite/*chemistry
MH  - *Hot Temperature
MH  - Paraffin/*chemistry
MH  - Polyethylene/*chemistry
MH  - Spectroscopy, Fourier Transform Infrared
MH  - Tensile Strength
MH  - Thermal Conductivity
MH  - Transition Temperature
MH  - Waxes/*chemistry
PMC - PMC6479558
OTO - NOTNLM
OT  - artificial aging
OT  - expanded graphite
OT  - leakage
OT  - paraffin wax
OT  - phase change materials
OT  - thermal conductivity
COIS- The authors declare no conflicts 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- 2019/03/31 06:00
MHDA- 2019/08/09 06:00
PMCR- 2019/03/28
CRDT- 2019/03/31 06:00
PHST- 2019/02/11 00:00 [received]
PHST- 2019/03/18 00:00 [revised]
PHST- 2019/03/21 00:00 [accepted]
PHST- 2019/03/31 06:00 [entrez]
PHST- 2019/03/31 06:00 [pubmed]
PHST- 2019/08/09 06:00 [medline]
PHST- 2019/03/28 00:00 [pmc-release]
AID - molecules24071217 [pii]
AID - molecules-24-01217 [pii]
AID - 10.3390/molecules24071217 [doi]
PST - epublish
SO  - Molecules. 2019 Mar 28;24(7):1217. doi: 10.3390/molecules24071217.