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dc.contributor.advisorSteyn, H. J. H.
dc.contributor.authorSeiphetlheng, Kgalalelo
dc.date.accessioned2015-07-28T09:42:00Z
dc.date.available2015-07-28T09:42:00Z
dc.date.issued2015-01
dc.identifier.urihttp://hdl.handle.net/11660/714
dc.description.abstractEnglish: Bleaches are used in the textile industry for brightening, whitening and cleaning fabrics. The two commonly used bleaches are hypochlorite and peroxide bleaches. Peroxide bleaches are used more often than chlorine bleaches in fabric finishing. Chlorine is a harsh chemical harmful to human health and may even destroy the cotton fibre if not monitored. It destroys the cellulose and that affects the quality of the bleached fabric. Large amounts of these bleaches are released into the environment through washing and they harm the environment and ozone layer. Hence, new and better ways of bleaching needs to be investigated. Electrochemically activated water (Anolyte) has been recently introduced to the food industries as a disinfecting agent. Disinfection with Anolyte has been successful and convenient because Anolyte is generated onsite by simple electrolysis of a dilute salt solution. The production of Anolyte requires lower production cost and hazards associated with handling, transportation and storage. Anolyte is stable and after 48 hours the solution become inactive water and can be discarded without causing harm to the environment. Although Anolyte has been successful in the food industry, extensive research has not been done to determine whether it can be used in the textile industry. The aim of this study was to investigate the effectiveness of Anolyte as a bleaching agent compared to the commonly used sodium hypochlorite. Distilled water was used as control. The efficacy of Anolyte was determined at 24°C 30°C, 40°C, 60°C and 80°C. The effect of Anolyte and sodium hypochlorite on bleached cotton, unbleached cotton, dyed cotton and stained cotton respectively were evaluated in terms of tensile strength, stiffness and whiteness. Further investigations were done on the effect of bleaching temperatures mentioned above and duration of exposure ranged from 9 minutes, 18 minutes, 30 minutes, 45 minutes, 60 minutes, 90 minutes and 120 minutes. The study was an experimental research where bleaching of samples was done according to AATCC Test Method 61- 2009 carried out in the Launder-Ometer. Reactive red dyed cotton, vat blue dyed cotton, bleached cotton and unbleached cotton were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength, stiffness and colour change. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The stiffness test ASTM D1388 – 08 the Cantilever principle was used. While AATCC test method 135-1985 for instructional colour measurement of textiles was used in determining colour change. 169 The results gathered from the study indicated that Anolyte was less effective than sodium hypochlorite as a stain remover for blood, tea, soot/mineral oil and blackcurrant juice. Anolyte caused more colour loss on coloured materials than sodium hypochlorite especially at high temperatures. Anolyte was less effective in bleaching unbleached cotton than sodium hypochlorite but without harming the tensile strength of the cotton. Although Anolyte caused dyed cotton to lose colour, the stiffness of the dyed cotton was less than that bleached with sodium hypochlorite, making the cotton fabric to be much softer and desirable. It was also gathered that sodium hypochlorite reduced the tensile strength of vat blue dyed cotton and bleached cotton more than Anolyte. However, Anolyte on the other hand reduced the tensile strength of reactive red dyed cotton more than sodium hypochlorite.en_ZA
dc.description.abstractAfrikaans: Bleikmiddels word in die industrie vir die verheldering, witmaking en die skoonmaking van tekstielstowwe gebruik. Die twee bleikmiddels wat mees algemeen gebruik word, is hipocloriet- en peroksiedbleikmiddels. Peroksiedbleikmiddels word meer dikwels as chloorbleikmiddels in tekstielafwerking gebruik. Chloor is ‘n skerp chemikalie wat skadelik is vir menslike gesondheid en kan selfs katoenvesels vernietig as dit nie goed gemonitor word nie. Dit vernietig die sellulose wat ‘n effek op die kwaliteit van die gebleikte stof het. Groot hoeveelhede van hierdie bleikmiddels word in die omgewing deur middel van waswater vrygelaat en dit besoedel die omgewing en die osoonlaag. Dus behoort nuwe en beter maniere van bleiking ondersoek te word. Elektrochemies geaktiveerde water (Anolyte) is onlangs aan die voedselindustrie as ‘n ontsmettingsmiddel bekendgestel. Ontsmetting met Anolyte is suksesvol en gerieflik omdat Anolyte in die werksplek geproduseer kan word deur ‘n eenvoudige elektroliese van ‘n verdunde soutoplossing. Die vervaardiging van Anolyte verg laer produksiekoste en die risiko’s wat met die hantering, vervoer en berging gepaard gaan. Anolyte is stabiel en na 48 uur raak dit weer onaktief en verander in normale water en word dit weggevoer sonder om die omgewing te beskadig. Alhoewel Anolyte suksesvol in die voedselindustrie gebruik word, is daar nog nie uitgebreide navorsing gedoen oor hoe dit in die tekstielindustrie gebruik kan word nie. Hierdie navorsing poog om die leemte te help vul. Die doel van hierdie studie was om die effektiwiteit van Anolyte as ‘n bleikingsmiddel te vergelyk met die algemeen gebruikte natriumhipochloriet. Gedistilleerde water is as kontrole gebruik. Anolyte se doeltreffendheid is getoets by 24°C, 30°C, 40°C, 60°C en 80°C. Die effek wat Anolyte en natriumhipochloriet op gebleikte -, ongebleikte -, gekleurde en aangevuilde katoen het, is geëvalueer in terme van treksterkte, styfheid en witheid. Verdere navorsing is gedoen om die effek van bleikingstemperatuur (soos bo genoem) en die duur van blootstelling wat gewissel het van 9, 18, 30, 45, 60, 90 en 120 minute te bepaal. Die studie was ‘n eksperimentele navorsingsondersoek waar monsters gebleik is volgens die AATCC 61-2009 toetsmetode en is in ‘n Launder-Ometer gedoen. Reaktiewe rooi gekleurde -, blou kuip gekleurde -, gebleikte – en ongebleikte katoen is vir 5, 10 of 20 siklusse respektiewelik gewas om die invloed op die treksterkte, styfheid en kleurverandering te evalueer. Die treksterkte toets is op ‘n Instron-toetser en ISO/SANS 13934-1:1999 uitgevoer. Die styfheidstoets ASTM D 1388-08, die vrybalkbeginsel is gebruik. Terwyl 171 die AATCC 135-1985 toetsmetode vir die instrumentele tekstielkleurmeting gebruik is om die kleurverandering te bepaal. Die resultate wat verkry is van hierdie studie dui aan dat Anolyte minder doeltreffend is as natriumhipochloriet om bloed, tee, roet/minerale olie en bloubessiesap vlekke te verwyder. Anolyte veroorsaak ook meer kleurverlies as natriumhipocloriet veral by hoër temperature. Dit laat ook gekleurde katoen, veral by hoë temperature en vele siklusse, kleur verloor. Anolyte was ook minder doeltreffend in bleiking van ongebleikte katoen, maar dit kan gebruik word op ongebleikte katoen sonder om die taaiheid van die stof te benadeel. Alhoewel Anolyte gekleurde katoen kleur laat verloor het, was die styfheid van gekleurde katoen minder as dié wat met natriumhipochloriet gebleik was. Dit maak die katoen veel sagter en meer aanvaarbaarder. Natriumhipochloriet het die treksterkte van die blou kuip gekleurde katoen en gebleikte katoen meer verminder as die Anolyte. Die Anolyte het egter die treksterkte van die rooi reaktiewe kleurstof gekleurde katoen meer verminder.
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.subjectRigidityen_ZA
dc.subjectStiffnessen_ZA
dc.subjectpHen_ZA
dc.subjectColour changeen_ZA
dc.subjectSodium hypochloriteen_ZA
dc.subjectBleachen_ZA
dc.subjectCottonen_ZA
dc.subjectAnolytesen_ZA
dc.subjectBleachingen_ZA
dc.subjectTextile industryen_ZA
dc.subjectPeroxidesen_ZA
dc.subjectDyes and dying -- Cottonen_ZA
dc.subjectThesis (Ph.D. (Consumer Science))--University of the Free State, 2015en_ZA
dc.titleAnolyte as an alternative bleach for cotton fabricsen_ZA
dc.typeThesisen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA


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