aalto1 untyped-item.component.html
Dope-dyeing of cellulosic fibres for sustainable textiles
Loading...
URL
Journal Title
Journal ISSN
Volume Title
School of Chemical Engineering |
Doctoral thesis (article-based)
| Defence date: 2025-09-26
Electronic archive copy is available via Aalto Thesis Database.
Unless otherwise stated, all rights belong to the author. You may download, display and print this publication for Your own personal use. Commercial use is prohibited.
Authors
Date
Major/Subject
Mcode
Degree programme
Language
en
Pages
89 + app. 60
Series
Aalto University publication series Doctoral Theses, 178/2025
Abstract
The textile industry is today one of the largest polluters in the world. It is estimated that 20 % of global clean water pollution can be attributed to textile production. Dyeing and finishing processes use an extensive amount of water and chemicals, and most of the effluents and wastewater is released into the environment. In this doctoral thesis, we explore dope-dyeing of man-made cellulosic fibres (MMCFs) with vat dyes and pigments using the IoncellĀ® process, circumventing the ubiquitous use of fresh water and potentially reducing effluents streams to a great extent. Dopedyeing is an established process for synthetic polymers but is not yet common for MMCFs. Regenerated cellulose fibres were produced through dissolution of dissolving pulp in the ionic liquid 1,5-diazabicyclo[4.3.0]non-5-ene acetate. The produced fibres were processed into yarn and a jersey fabric was knitted. Mechanical and colour fastness properties were tested. The fibres properties were also assessed through SEM, birefringence, and crystallinity measurements. Fibres with excellent mechanical properties (tenacity higher than 50 cN/tex and an elongation between 10 and 13%). The dope-dyed fibres showed excellent colour fastness against abrasion, light, and washing, with most samples receiving the highest or second highest performance grade. The dopedyed fabric samples performed only slightly worse in abrasion resistance than the undyed fabric.
The IoncellĀ® technology enables a near closed-loop system in the future, where the dopedyed fibres also hold great potential to be recycled themselves without colour change or loss in colour intensity. The goal in the future is to reach a system similar to paper recycling where most of the raw material is recycled. Textiles with colours produced in large quantities such as black or navy blue could be the first market entry point. Dope-dyeing can also be used to add or recycle pigments, such as TiO2, to fibres meant for nonwoven production. The pigments are commonly used in the nonwoven industry as whitening agents and for their antimicrobial properties. Currently the market is dominated by synthetic fibres and not only because of the recent directive on single-use plastics from the European Union, the need for alternative materials is growing. A rise in awareness among consumers about the drawbacks of fast fashion and its impact on the environment has led to a change in consumer behaviour. The need for biobased and biodegradable fibres is growing fast. Currently, for example viscose and Tencel can be found on the market, but many Finnish innovations are looking for their place on the market.
Tekstiiliteollisuus on nykypƤivƤnƤ yksi suurimmista ympƤristƶnsaastuttajista. Arviolta noin 20 % maailmanlaajuisesta puhtaan veden saastumisesta johtuu tekstiilituotannosta. VƤrjƤys- ja jƤlkikƤsittelyprosessit kuluttavat paljon puhdasta vettƤ ja kemikaaleja, ja suuri osa jƤtevedestƤ pƤƤtyy vesistƶihin. TƤssƤ vƤitƶskirjassa on tutkittu regeneroitujen selluloosakuitujen kehruuvƤrjƤystƤ kyyppivƤreillƤ ja pigmenteillƤ kƤyttƤen IoncellĀ®-prosessia. MenetelmƤmme korvaa erillisen vƤrjƤysvaiheen, joka kuluttaa paljon puhdasta vettƤ, energiaa ja kemikaaleja, sekƤ potentiaalisesti vƤhentƤƤ pƤƤstƶjƤ merkittƤvƤsti. KehruuvƤrjƤys on vakiintunut prosessi synteettisille polymeereille, mutta ei ole vielƤ yleinen regeneroitujen selluloosakuitujen valmistuksessa. Ioncellprosessissa kuidut valmistettiin liuottamalla selluloosaa ioniseen nesteeseen 1,5-diatsabisyklo[4.3.0]non-5-eeniasetaattiin. Kehruuliuos kehrƤttiin sitten kuivasuihkumƤrkƤkehrƤyksellƤ. Valmistetut kuidut kehrƤttiin langaksi ja valmistettiin edelleen jersey-kankaaksi. Kuitujen mekaanisia ominaisuuksia kuten vetolujuutta ja elastisuutta mitattiin ja nƤytteiden vƤrinkestƤvyyttƤ testattiin erilaisin menetelmin. Kuitujen ominaisuuksia arvioitiin myƶs mikroskopialla (SEM), kahtaistaitteisuusmittauksilla sekƤ mƤƤrittƤmƤllƤ nƤytteiden kiteisyyttƤ. KehruuvƤrjƤtyt Ioncell-kuidut saavuttivat samankaltaisia arvoja kuin vƤrjƤƤmƤttƶmƤt Ioncell-kuidut. Vetolujuus oli jopa yli 50 cN/tex asti, mikƤ ylittƤƤ useimmat kaupalliset selluloosapohjaiset kuidut. NƤytteiden venyvyys vaihteli 10 ja 13 % vƤliltƤ. Kuidut osoittivat myƶs erinomaista vƤrinkestƤvyyttƤ valoa, pesua ja hankausta vastaan. VƤrjƤttyjen kankaiden kulutuskestƤvyys oli lƤhes samaa luokkaa vƤrjƤƤmƤttƶmien kankaiden kanssa.
IoncellĀ®-teknologia mahdollistaa myƶs sen, ettƤ prosessissa kƤytettƤvƤƤ ionista nestettƤ ja vettƤ pystytƤƤn kierrƤttƤmƤƤn. LisƤksi tutkimuksemme on osoittanut, ettƤ tekstiilit ja niiden vƤriaineet voidaan kierrƤttƤƤ uudelleen, ilman ettƤ ominaisuudet tai vƤrisƤvy heikkenevƤt merkittƤvƤsti. Tulevaisuuden tavoitteena on saavuttaa tekstiileille samankaltainen kierrƤtysjƤrjestelmƤ kuin paperilla nykyisin, jossa suurin osa raaka-aineesta on kierrƤtettyƤ ja vain pieni osa tarvittavasta raaka-aineesta on uutta materiaalia. Tekniikkaa voitaisiin soveltaa ensiksi vƤreille, joita tuotetaan isoissa mƤƤrissƤ, kuten musta ja tummansininen. Samaa tekniikkaa voidaan kƤyttƤƤ muille tekstiileille kuin vaatteille. Kuitukangasteollisuudessa lisƤtƤƤn usein TiO2 pigmenttiƤ optisten ja antibakteeristen ominaisuuksien parantamiseksi ja tƤssƤ tyƶssƤ todettiin tƤmƤn menetelmƤn soveltuvan myƶs regeneroidulle selluloosakuiduille. Kuluttajien tietoisuus pikamuodin haitoista ja sen ympƤristƶvaikutuksista on lisƤƤntynyt ja tƤmƤ on alkanut vaikuttaa asiakaskƤyttƤytymiseen. Biopohjaisten ja biohajoavien kuitujen tarve on nopeasti kasvanut; markkinoilla on tƤllƤ hetkellƤ esimerkiksi viskoosia ja TenceliƤ. Uusia innovaatioita tarvitaan tuottamaan kuituja entistƤ ympƤristƶystƤvƤllisemmin.
Description
Supervising professor
Hummel, Michael, Assoc. Prof., Aalto University, Department of Bioproducts and Biosystems, FinlandThesis advisor
Schlapp-Hackl, Inge, Dr., Aalto University, Department of Bioproducts and Biosystems, FinlandRissanen, Marja, Dr., TAMK, Finland
Other note
Parts
- [Publication 1]: Nygren, Nicole; Schlapp-Hackl, Inge; Heimala, Senni; Sederholm, Helena; Rissanen, Marja; Hummel, Michael. 2024. Spin-dyeing of cellulose fibres with vat dyes using the Ioncell process. Carbohydrate Polymers. 2024, Volume 346, 122578. ISSN 0144-8617.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-202409046172DOI: 10.1016/j.carbpol.2024.122578 View at publisher
- [Publication 2]: Nygren, Nicole; Langhans, Marike; Schlapp-Hackl, Inge; Heimala, Senni; Westerback, Helena; Rissanen, Marja; Hummel, Michael. Production and recycling of dope-dyed lyocell fibres with pigment dyes. ACS Sustainable Resource Management. 2025, Volume 2, Issue 6, 1139-1146.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-202508045744DOI: 10.1021/acssusresmgt.5c00165 View at publisher
- [Publication 3]: Nygren-Sundell, Nicole; Hart, Emily; Schlapp-Hackl, Inge; Reiska, Eva; Badara, Olamide; Raipale, Noora; Kesari, Kavindra; Vuorinen, Tapani; Hummel, Michael. Straw and recycled nonwovens as alternative cellulose sources for nonwoven materials. Accepted for publication in the journal Cellulose in the year 2025