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[{"key": "dc.contributor.advisor", "value": "Lappalainen, Timo", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.advisor", "value": "Louhelainen, Jarmo", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "J\u00e4rvinen, Marjo", "language": "", "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2024-11-22T11:56:18Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2024-11-22T11:56:18Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2024", "language": "", "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/98593", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "T\u00e4ss\u00e4 Pro gradu tutkielmassa tutkittiin vaahtorainaamalla valmistettujen selluloosakuituvahvisteisten termoplastisten komposiittien hydrofobisia, rakenteellisia ja lujuusominaisuuksia. Komposiiteissa k\u00e4ytettiin hydrofobointikemikaaleina maleiinihappoanhydridilla oksastettuja polymeerej\u00e4, alkyyliketeenidimeerej\u00e4 (AKD) ja hartsiestereit\u00e4. Vaahtorainaus on uusi menetelm\u00e4, joka s\u00e4ilytt\u00e4\u00e4 selluloosakuitujen pituuden ja parantaa n\u00e4in komposiitin lujuutta. Selluloosakuituvahvisteisten komposiittien hydrofobisuuden tutkiminen on t\u00e4rke\u00e4\u00e4, koska luonnonkuidut ovat alttiita hajoamiselle.\n\nKirjallisuusosassa esitell\u00e4\u00e4n kuituvahvisteisten termoplastisten komposiittien l\u00e4ht\u00f6materiaaleja ja valmistusmenetelmi\u00e4, keskittyen erityisesti vaahtorainausteknologiaan. Lis\u00e4ksi esitell\u00e4\u00e4n kemiallisia k\u00e4sittelyj\u00e4, jotka parantavat kuitujen hydrofobisuutta ja adheesiota. Erityisesti keskityt\u00e4\u00e4n niihin menetelmiin, joita k\u00e4ytettiin kokeellisessa osassa. Lis\u00e4ksi tarkastellaan veden tunkeutumisen ja imeytymisen mekanismeja sek\u00e4 menetelmi\u00e4 hydrofobisuuden mittaamiseen. Kokeellisessa osassa valmistettiin vaahtorainattuja komposiitteja, jotka koostuivat 30 paino-% termoplastisesta polymeerimatriisista ja 70 paino-% selluloosakuiduista ja jotka k\u00e4siteltiin hydrofobisilla kemikaaleilla. Valmistus tehtiin kaksivaiheisella prosessilla, johon kuuluivat vaahtorainaus sek\u00e4 l\u00e4mp\u00f6muovaus. Kemiallisten k\u00e4sittelyjen vaikutuksia hydrofobisiin ominaisuuksiin karakterisoitiin veden kontaktikulmamittauksilla, Cobb-testeill\u00e4 ja kosteuspitoisuuden mittauksilla upottamalla n\u00e4yte 20 \u00b0C veteen. Muita mitattuja ominaisuuksia olivat neli\u00f6paino, paksuus, tiheys, r\u00f6ntgenmikrotomografia, v\u00e4ri, FTIR-ATR ja lujuus.\n\nTulokset osoittivat, ett\u00e4 kaikki kemialliset k\u00e4sittelyt tarjosivat tehokkaan suojan vesiroiskeilta perustuen kontaktikulmamittaukseen vedell\u00e4. Maleiinihappoanhydridilla oksastetut polymeerit sek\u00e4 AKD tarjosivat my\u00f6s erinomaisen suojan vesikerrosta vastaan mitattuna Cobb600 mittauksella, kun taas hartsiesterit osoittivat vaihtelevaa suorituskyky\u00e4. Veden tunkeutumisen kest\u00e4vyys kahden p\u00e4iv\u00e4n upotustestiss\u00e4 oli heikko kaikilla vaahtorainatuilla komposiiteilla n\u00e4ytteiden huokoisuudesta johtuen. Maleiinihappoanhydridilla oksastetut polymeerit ja AKD hidastivat tunkeutumista tehokkaimmin, todenn\u00e4k\u00f6isesti vahvojen kuitusidosten vuoksi, kun taas hartsiesterit olivat v\u00e4hemm\u00e4n tehokkaita heikomman sidoskyvyn vuoksi. Vaahtorainatuilla komposiiteilla oli erinomaiset lujuusominaisuudet. Kemialliset lis\u00e4aineet eiv\u00e4t parantaneet lujuusominaisuuksia referenssitasoon verrattuna. Johtop\u00e4\u00e4t\u00f6ksen\u00e4 on, ett\u00e4 vaahtorainaamalla valmistetut komposiitit sopivat hyvin sovelluksiin, joissa tarvitaan suojaa vesiroiskeilta ja lyhytaikaiselta altistukselta ohuilta vesikerroksilta, mutta soveltuvat \u00e4\u00e4riolosuhteisiin vain erillisen pinnoitekerroksen kanssa.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "This thesis investigated the hydrophobic properties, alongside structural and strength properties, of foam-formed cellulose fiber-reinforced thermoplastic composites treated with maleic anhydride grafted polymers, alkyl ketene dimers (AKD), and rosin esters. Foam-forming is a novel technique that maintains cellulose fibers' length, enhancing composite strength. The hydrophobicity of cellulose fiber-reinforced composites is an important topic, as materials containing natural fibers are prone to degradation.\n\nThe literature part introduces raw materials and manufacturing methods for thermoplastic composites, focusing on foam-forming technology. It also covers chemical treatments enhancing hydrophobicity and fiber adhesion, particularly those applied in the experimental part. Additionally, water penetration and absorption mechanisms and methods for evaluating material hydrophobicity are discussed. In the experimental part, foam-formed composites, comprising 30 wt% thermoplastic polymer matrix and 70 wt% cellulose fibers, were produced in a two-phase process including foam-forming and thermoforming phases, and treated with hydrophobic chemicals during the foam-forming phase. The effects of these chemical treatments on hydrophobic properties were evaluated using water contact angle, Cobb test, and moisture content during immersion at 20\u00b0C. Additional measurements included grammage, thickness, density, X-ray tomography, color analysis, FTIR-ATR, and strength properties.\n\nThe results indicated that all chemical treatments provided effective water splash protection as demonstrated by water contact angle measurements. Maleic anhydride grafted polymers and AKD also provided excellent repellency against water puddles, as indicated by Cobb600 results, while some rosin ester products exhibited good but variable performance. Resistance to water penetration during 2-day immersion was generally poor due to the porosity of the composite; however, maleic anhydride grafted polymers and AKD resisted water penetration most effectively, likely due to strong bonding with cellulose fibers. Rosin esters were less effective, possibly due to weaker fiber contact. The composites displayed excellent strength properties overall. The chemical additions did not enhance strength properties beyond the untreated levels. In conclusion, foam-formed composites studied in this thesis are suitable for applications requiring resistance to water splashes and puddles but are recommended for extreme conditions only with a separate coating layer.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Paivi Vuorio (paelvuor@jyu.fi) on 2024-11-22T11:56:16Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2024-11-22T11:56:18Z (GMT). No. of bitstreams: 0\n Previous issue date: 2024", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "169", "language": "", "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.language.iso", "value": "eng", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "hydrophobicity", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "foam-forming", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "fiber-reinforced", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Hydrophobicity of foam-formed cellulose fiber-reinforced thermoplastic composites", "language": "", "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-202411227424", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Matemaattis-luonnontieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Kemian laitos", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Department of Chemistry", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Kemia", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Chemistry", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "yvv.contractresearch.collaborator", "value": "business", "language": "", "element": "contractresearch", "qualifier": "collaborator", "schema": "yvv"}, {"key": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"key": "yvv.contractresearch.initiative", "value": "student", "language": "", "element": "contractresearch", "qualifier": "initiative", "schema": "yvv"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "restrictedAccess", "language": null, "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "4038", "language": "", "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "komposiitit", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "polymeerit", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "selluloosa", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "kestomuovi", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "composites", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "polymers", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "cellulose", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "thermoplastic", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}, {"key": "dc.rights.accessrights", "value": "Tekij\u00e4 ei ole antanut lupaa avoimeen julkaisuun, joten aineisto on luettavissa vain Jyv\u00e4skyl\u00e4n yliopiston kirjaston <a href=\"https://kirjasto.jyu.fi/kokoelmat/arkistotyoasema\">arkistoty\u00f6asemalta</a>.", "language": "fi", "element": "rights", "qualifier": "accessrights", "schema": "dc"}, {"key": "dc.rights.accessrights", "value": "<br><br>The author has not given permission to make the work publicly available electronically. Therefore the material can be read only at the archival <a href=\"https://kirjasto.jyu.fi/collections/archival-workstation\">workstation</a> at Jyv\u00e4skyl\u00e4 University Library reserved for the use of archival materials.", "language": "en", "element": "rights", "qualifier": "accessrights", "schema": "dc"}]
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