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[{"key": "dc.contributor.advisor", "value": "Louhelainen, Jarmo", "language": null, "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Tirkkonen, Elisa", "language": null, "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2025-06-09T13:02:57Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2025-06-09T13:02:57Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2025", "language": null, "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/103271", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "T\u00e4ss\u00e4 Pro gradu -tutkielmassa tarkasteltiin, kuinka vaahdon ominaisuudet muuttuvat eri fysikaalisten ja kemiallisten muuttujien vaikutuksesta. Fysikaalisia muuttujina oli vaahdotustapa, joista toinen oli sekoittaminen ja toinen ilman sy\u00f6tt\u00e4minen. Sekoittamista k\u00e4ytett\u00e4ess\u00e4 testattiin eri sekoitusnopeuksia ja sy\u00f6tett\u00e4ess\u00e4 ilmaa kasvatettiin sy\u00f6tett\u00e4v\u00e4n ilman m\u00e4\u00e4r\u00e4\u00e4. Kemiallisina muuttujina olivat kokoajan kaksi eri pinta-aktiivista ainetta, eli tensidi\u00e4. Toinen tensidi oli anioninen ja toinen ei-ioninen. Tensidim\u00e4\u00e4r\u00e4n, retentioaineen ja liiman suhteen vaikutusta vaahdon ominaisuuksiin tarkasteltiin. N\u00e4m\u00e4 kaikki testit tehtiin kolmelle eri kuitutyypille, joista kaksi oli valkaistua kemiallisesti valmistettua sellua ja yksi oli valkaistu kemikuumahierre. Lis\u00e4ksi testattiin mikrofibrilloidun selluloosan (MFC) prosentuaalisen m\u00e4\u00e4r\u00e4n vaikutusta vaahdon ominaisuuksiin. Eri muuttujien vaikutusta pintaj\u00e4nnitykseen seurattiin tensiometrill\u00e4. Kirjallisuusosiossa esiteltiin vaahtojen ja tensidien ominaisuuksia, tarkasteltiin, kuinka erilaiset kuidut ja paperinvalmistuskemia vaikuttavat vaahdon ominaisuuksiin. Lopuksi tarkasteltiin my\u00f6s vaahtorainaamisprosessia ja vaahdon laadunhallintaa niiss\u00e4.\nIlman sy\u00f6tt\u00f6\u00e4 ei voitu k\u00e4ytt\u00e4\u00e4 eri kuitujen vaahdon ominaisuuksien vertailuun, sill\u00e4 kuidut eiv\u00e4t tarttuneet kupliin, vaan j\u00e4iv\u00e4t omaksi kerrokseksi vesifaasiin. Sekoittamisnopeudella havaittiin olevan suuri merkitys ilmapitoisuuteen ja erityisesti kuplakokoon. Kemiallisilla muuttujilla ei ollut suurta vaikutusta kuplakokoon, johtuen luultavasti siit\u00e4, ett\u00e4 kaikki testit tehtiin sekoittamalla. Kemiallisista muuttujista suurin merkitys oli tensidin m\u00e4\u00e4r\u00e4ll\u00e4. MFC:n m\u00e4\u00e4r\u00e4ll\u00e4 havaittiin vaikutus vaahdon ilmapitoisuuteen. Massan valmistustapa vaikutti ominaisuuksiin, kemikuumahierre tuotti korkeamman ilmapitoisuuden kuin valkaistu kemiallinen massa.\nPintaj\u00e4nnityst\u00e4 ei voitu mitata kuitupitoisesta n\u00e4ytteest\u00e4, joten kuidut suodatettiin. Pintaj\u00e4nnitys muuttui tensidim\u00e4\u00e4r\u00e4n muuttuessa. Paperinvalmistuskemia ei osoittanut pinta-aktiivisuutta. Mik\u00e4\u00e4n kuitu ei ollut pinta-aktiivinen sakeudessa 1.2 %, alkuper\u00e4isess\u00e4 sakeudessa kemikuumahierre osoitti pinta-aktiivisuutta.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "The target of this Master\u2019s thesis was to investigate foam properties with different physical and chemical variables. The physical variables were how foam was produced, air injection compared to mixing. Within those variables, the air flow rate and mixing speed were varied. The chemical variables were two different surface active chemicals (surfactants) with different ionic natures, one anionic and one non-ionic. Other chemicals added were retention aid and sizing agent. The amount of surfactant was varied as well. All of these were tested with three different types of pulp, two of which were bleached chemical pulps and one was bleached chemi-thermomechanical pulp. The addition of microfibrillated cellulose (MFC) was tested. Surface tension values were monitored with different variables. The literature review covered the basic principles of foams and surfactants and how fibers and papermaking chemistry affect the properties of foam. The foam forming process was reviewed as well as how to control foam properties in foam forming processes.\nAir injection tests could not be conducted with the pulps because the pulp separated into its phase rather than blending into the foam. Mixing speed, surfactant concentration, and the dose of MFC had the most effect on the air content of the foam. The addition of a retention aid and sizing agent did not affect noticeably the air content. The mixing speed affected the bubble size. As mixing was used to produce the foam for most tests, bubble size did not change drastically as chemical variables were varied. The procedure of how the pulp is manufactured, however, had a noticeable effect on air content, with the chemi-thermomechanical pulp producing the highest air content.\nSurface tensions could not be measured from the pulp slurry as the fibers interfered with the measurement. The fibers were filtrated, only the liquid part was measured. None of the pulps showed surface activity at a diluted concentration of 1.2 %. Chemi-thermomechanical pulp showed surface activity at the original consistency of 2.2 %, but chemical pulps did not. The retention aid and sizing agent did not show surface activity.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Jutta Aalto (aalto@jyu.fi) on 2025-06-09T13:02:57Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2025-06-09T13:02:57Z (GMT). No. of bitstreams: 0\n Previous issue date: 2025", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "104", "language": null, "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": null, "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "", "language": null, "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Foam quality control for foam forming fiber-based products", "language": null, "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-202506095072", "language": null, "element": "identifier", "qualifier": "urn", "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": null, "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": null, "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": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.copyright", "value": "\u00a9 The Author(s)", "language": "fi", "element": "rights", "qualifier": "copyright", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "openAccess", "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.yso", "value": "vaahdot", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "pinta-aktiiviset aineet", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "pintaj\u00e4nnitys", "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"}]
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