Investigating over-hygroscopic moisture sorption in paper fiber networks using Differential Scanninng Calorimetry (DSC)
(2024) In LUTVDG/TVBM VBMM01 20241Division of Building Materials
- Abstract
- The climate changes that are happening at the moment have never been clearer, and as the world moves toward a greener economy, more consumers are seeking recyclable and climate-friendly packages with minimal environmental impact. This growing demand presents an opportunity to develop packages that support a low-carbon, circular economy without compromising food safety. Several companies are focusing on this, including Tetra Pak, which is working to innovate in the field of sustainable packaging solutions using “paper-carton”.
To be able to design new packages consisting of “paper-carton”, the characterization of the maximum cell wall moisture content in plant fiber materials, to be used in packaging materials, is of great importance to... (More) - The climate changes that are happening at the moment have never been clearer, and as the world moves toward a greener economy, more consumers are seeking recyclable and climate-friendly packages with minimal environmental impact. This growing demand presents an opportunity to develop packages that support a low-carbon, circular economy without compromising food safety. Several companies are focusing on this, including Tetra Pak, which is working to innovate in the field of sustainable packaging solutions using “paper-carton”.
To be able to design new packages consisting of “paper-carton”, the characterization of the maximum cell wall moisture content in plant fiber materials, to be used in packaging materials, is of great importance to explore and understand. Since paper-based materials are composite material structures primarily consisting of pulp fibers extracted from wood, the mechanical performance of the fibers and fiber network are strongly impacted by absorption of moisture. Therefore, fundamental understanding and material characterization of sorption properties are important when designing sustainable paper-based products.
This master thesis focuses on developing a methodology to be able to quantify the amount of cell wall moisture content and capillary water in paper and pulp fiber networks, as well as how to determine the cell wall moisture content and capillary water in paper and pulp fiber networks evolve over time. This was done by developing a methodology using Differential Scanning Calorimetry (DSC) to characterize the maximum cell wall moisture content, that is practical for industrial material characterization. Experimental work was conducted at the division of Building Materials, Faculty of Engineering, Lund University. The investigated materials were provided by Tetra Pak in Lund.
One softwood, Norway spruce, and one hardwood, birch, was included in the experiments as reference materials. Experiments performed showed that cell wall moisture content for spruce was in the range 40-42% while for birch it was 40-45%. Different paper materials were studied, with focus on a paper material used in production of paper drinking straws. The cell wall moisture content of this paper material was 41-48%. Some other paper materials were also tested, and they showed some variation in cell wall moisture content, where the average cell wall moisture content was 40-45%, except for one material that was slightly lower. Experiments performed to determine the evolution of the free and bound water over time showed that this is very material dependent. For one paper material it took just a few hours to reach the maximum cell wall moisture content, while for another material it took more than a day.
The conclusion of this thesis is that the developed methodology provides results on how to quantify the free and bound water in paper-based materials using DSC. The method can also determine the free and bound water evolution over time. Results showed that the cell wall moisture content for the woods and paper materials studied in this work are very similar using DSC as method. The results also showed that the evolution of free and bound water in paper and pulp fiber networks is very material dependent. (Less) - Popular Abstract (Swedish)
- Trött på att papperssugrör inte fungerar?
Övergången från plast till papper vad gäller flertalet förpackningar har nog inte undgått någon. Många har säkert delat frustrationen över att formen på ett papperssugrör ger upp redan efter ett fåtal minuter jämfört med plastsugrör. I vår studie ligger därför fokus på att utveckla en metod för att kvantifiera mängden vatten i träfibrernas cellvägg för att utveckla existerande simuleringsmodeller för tillverkning av papperssugrör.
Då världen försöker övergå till en grönare ekonomi, söker en majoritet av världens konsumenter efter förpackningar som är återvinningsbara, bättre för klimatet och med en låg miljöpåverkan. En övergång från plast till papper har därför blivit mer eller mindre... (More) - Trött på att papperssugrör inte fungerar?
Övergången från plast till papper vad gäller flertalet förpackningar har nog inte undgått någon. Många har säkert delat frustrationen över att formen på ett papperssugrör ger upp redan efter ett fåtal minuter jämfört med plastsugrör. I vår studie ligger därför fokus på att utveckla en metod för att kvantifiera mängden vatten i träfibrernas cellvägg för att utveckla existerande simuleringsmodeller för tillverkning av papperssugrör.
Då världen försöker övergå till en grönare ekonomi, söker en majoritet av världens konsumenter efter förpackningar som är återvinningsbara, bättre för klimatet och med en låg miljöpåverkan. En övergång från plast till papper har därför blivit mer eller mindre naturlig, dock inte helt utan att föra med sig en del problem. Pappersmaterial är utvunnet från trä vars mekaniska prestanda är starkt relaterad till fukt, och därmed absorptionen av vatten. För att utveckla pappersförpackningar är därför mängden vatten i träfibrernas cellväggar, d.v.s. cellväggens fuktkvot, av stort intresse. Detta då cellväggsfuktkvoten visar på vilken maximal mängd vatten cellväggen kan erhålla vid vattenmättning. Faktorer som påverkar cellväggsfuktkvoten i papper är bland annat vilka träslag pappret består av, dess ytbehandling samt vilka tillsatser som använts i pappersmassan.
Studien syftade därför till att utveckla en metod, för att kvantifiera mängden vatten i cellväggen, i pappers- och fiberbaserade material som vidare kan användas till att utveckla existerande simuleringsmodeller av pappersförpackningar. Studien syftade även till att utveckla en metod för att kvantifiera förändringen av mängden vatten i cellväggen över tid. Detta gjordes med hjälp av mätinstrumentet Differential Scanning Calorimetry även kallad DSC. Förenklat förklarat placeras ett prov i DSC-instrumentet vartefter provet frystes. I teorin skall cellväggsvattnet inte vara frysbart utan bara övrigt vatten ska frysas. DSC:n mätte då värmen från det övriga vattnet som smälte vilket möjliggjorde beräkningar av cellväggsfuktkvoten.
Resultatet från studien blev lyckat, då en metod för att kvantifiera cellväggsfuktkvoten utvecklades i pappers- och fiberbaserade material, vilken var reproducerbar. Studien visade även på att cellväggsfuktkvoten generellt var snarlik vad gäller papper och trä för de material som testades i studien, samt att det fanns en koppling mellan cellväggsfuktkvoten och tiden som provet utsattes för vatten. Beroende på materialstrukturen i de individuella pappersmaterialen varierade däremot cellväggsfuktkvoten något mellan materialen. Förändringen över tid vad gäller cellväggsfuktkvoten, för de olika pappersmaterialen i studien, visade sig även vara materialberoende. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9177392
- author
- Sturesson, Karl LU
- supervisor
- organization
- course
- VBMM01 20241
- year
- 2024
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- DSC, solute exclusion, WRV, paper, wood, moisture, maximum cell wall moisture content, sorption, FSP
- publication/series
- LUTVDG/TVBM
- report number
- 5139
- other publication id
- LUTVDG/TVBM-24/5139-SE
- language
- English
- id
- 9177392
- date added to LUP
- 2024-11-05 15:24:02
- date last changed
- 2024-11-05 15:24:02
@misc{9177392,
abstract = {{The climate changes that are happening at the moment have never been clearer, and as the world moves toward a greener economy, more consumers are seeking recyclable and climate-friendly packages with minimal environmental impact. This growing demand presents an opportunity to develop packages that support a low-carbon, circular economy without compromising food safety. Several companies are focusing on this, including Tetra Pak, which is working to innovate in the field of sustainable packaging solutions using “paper-carton”.
To be able to design new packages consisting of “paper-carton”, the characterization of the maximum cell wall moisture content in plant fiber materials, to be used in packaging materials, is of great importance to explore and understand. Since paper-based materials are composite material structures primarily consisting of pulp fibers extracted from wood, the mechanical performance of the fibers and fiber network are strongly impacted by absorption of moisture. Therefore, fundamental understanding and material characterization of sorption properties are important when designing sustainable paper-based products.
This master thesis focuses on developing a methodology to be able to quantify the amount of cell wall moisture content and capillary water in paper and pulp fiber networks, as well as how to determine the cell wall moisture content and capillary water in paper and pulp fiber networks evolve over time. This was done by developing a methodology using Differential Scanning Calorimetry (DSC) to characterize the maximum cell wall moisture content, that is practical for industrial material characterization. Experimental work was conducted at the division of Building Materials, Faculty of Engineering, Lund University. The investigated materials were provided by Tetra Pak in Lund.
One softwood, Norway spruce, and one hardwood, birch, was included in the experiments as reference materials. Experiments performed showed that cell wall moisture content for spruce was in the range 40-42% while for birch it was 40-45%. Different paper materials were studied, with focus on a paper material used in production of paper drinking straws. The cell wall moisture content of this paper material was 41-48%. Some other paper materials were also tested, and they showed some variation in cell wall moisture content, where the average cell wall moisture content was 40-45%, except for one material that was slightly lower. Experiments performed to determine the evolution of the free and bound water over time showed that this is very material dependent. For one paper material it took just a few hours to reach the maximum cell wall moisture content, while for another material it took more than a day.
The conclusion of this thesis is that the developed methodology provides results on how to quantify the free and bound water in paper-based materials using DSC. The method can also determine the free and bound water evolution over time. Results showed that the cell wall moisture content for the woods and paper materials studied in this work are very similar using DSC as method. The results also showed that the evolution of free and bound water in paper and pulp fiber networks is very material dependent.}},
author = {{Sturesson, Karl}},
language = {{eng}},
note = {{Student Paper}},
series = {{LUTVDG/TVBM}},
title = {{Investigating over-hygroscopic moisture sorption in paper fiber networks using Differential Scanninng Calorimetry (DSC)}},
year = {{2024}},
}