Textilkemi med miljökemi, skriftlig tentamen 6,0 hp

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1 Textilkemi med miljökemi 7,5 högskolepoäng Provmoment: Textilkemi med miljökemi, skriftlig tentamen 6,0 hp Ladokkod: TTM011 Tentamen ges för: TI13, TI12 och Exchange Ten 15 TentamensKod: Tentamensdatum: Tid: 09:00-13:00 Hjälpmedel: Språklexikon, Language dictionary Totalt antal poäng på tentamen: 110 För att få respektive betyg krävs: Underkänd Godkänd Väl godkänd 0-43,5 poäng 44-87,5 poäng poäng (ECTS grades: F: 0-22p, Fx: 23-43,5p, E: 44-56,5p, D: 57-69,5p, C: 70-82,5p, B: 83-95,5p, A: p) Rätningstid: Ca tre veckor Anscarig lärare: Kenneth Tingsvik

2 Exam/Re-exam in Textile chemistry and Environmental chemistry for TI13, TI12 and Exchange TEN15, 6 hp, (TTM011) Teacher: Kenneth Tingsvik Question 1 (10p) 1a) Discuss briefly the purpose of the following four process steps in the process for regular viscose fibre production: (6p) steeping (i.e. treatment with strong NaOH (aq.)) ageing xanthation ripening 1b) Another so-called regenerated cellulose fibre is the lyocell fibre. The Lyocell fibre has many excellent properties. However its tendency of fibrillation often is a disadvantage. Discuss briefly: (4p) the morphological reason for the fibrillation what special measures could be taken in the finishing of lyocell fibres to reduce the effects of fibrillation Question 2 (10p) In appendix 1 the chemical structures of different monomers are shown. Select appropriate monomers and show the chemical structures of the following polymers: (Structures containing at least four monomers are requested.) the polymer in a polyester fibre the polymer in a polyamide fibre the polymer Keratin in wool fibres the main polymer in an acrylic fibre the polymers in cotton fibres Question 3 (5p) 3a) Which fibres are built up by a polymer formed by the monomers below. (2p) H 2 N NH 2 HOOC COOH 3b) Fibres, which consist of the polymer in the question above, have very special properties and use to be called high performance fibres. Describe briefly the morphological structure of the fibres, which gives these special properties.

3 Question 4 (10p) 4a) Explain the phenomena surface tension of a liquid and show with a schematic drawing how an anion tenside reduces the surface tension. (4p) (For the tenside the symbol below could be used.) 4b) Cation tensides, containing a quaternary ammonium group, could be used to improve the wash-fastness of a cotton fabric dyed with direct dyes. Below a structure of such a tenside is shown. Explain and show with a schematic formula how the improvement of the wash-fastness is achieved. (For the direct dye you could use the symbol D - ) C 17 H 35 CH 3 N Cl C 17 H 35 4c) Describe briefly what is stated about detergents in the EU Regulation about detergents (Regulation No 648/2004) from 2004 including what the terms ultimate biodegradation and primary biodegradation stand for? CH 3 Question 5 (25p) 5a) Discuss briefly the requirements for a chemical structure to be coloured. (4p) Below the structure of a textile dye is shown. H 2 N N N NH 3 X 5b) To which dye class does this dye belong? (1p) 5c) What kind of chromophore contains the dye? (1p) 5d) This kind of dye is mainly used for dyeing of acrylic fibres. Show a schematic chemical reaction for the fixation of this dye to the fibre. (Appropriate symbols could be used for the fibre and the dye. For example the fibre could be symbolized by:

4 5e) For the dyeing in the question above a dye auxiliary of the type shown below could be used. Describe briefly how this auxiliary gives a more uniform dyeing result. Benzyl trimethylammonium chloride 5f) The structure below is a schematic model of a so-called leucoester vat dye. Describe the (continuous) dyeing process for dyeing of a cotton fabric with such dyes (i.e. the different steps in the dyeing process) and show the main chemical reactions of the dye model in the dyeing process. (8p) SO 3 Na O R Model for a leucoester vat dye O SO 3 Na R 1 5g) Certain dyes could react according to the reaction formula below. Discuss briefly the possible health impact of such dyes and the legislation in EU concerning such dyes. (5p) reduktion

5 Question 6 (10p) 6a) Below the structures of some chemicals (resins) used for easy-care finishing of cotton are shown. Explain how each of these resins works for giving the crease resistant effect. (No chemical formulas are requested.) DMDHEU 6b) The nowadays dominating resins for easy-care finishing are based on DMDHEU, dimethyloldihydroxyethyleneurea (see the structure above). In order to reduce the formaldehyde release of easy-care finishes different measures could be taken. Discuss at least five different measures to reduce the formaldehyde content/formaldehyde release of an easy-care finished cotton fabric. (7p) Question 7 (10p) 7a) Mention the necessary conditions (prerequisites) for a textile surface to show superhydrophobic properties (i.e. equilibrium contact angle >150 ). 7b) Discuss briefly the environmental and health impact of traditional fluorocarbons and what measures that have been taken in recent years in order to reduce such impact. Mention also about the legislation concerning such fluorocarbons. (5p) 7c) Describe briefly a so-called LAD-fluorocarbon repellent. (2p) Question 8 (10p) 8a) Below the structure of a phosphorous based flame retardant agent is shown. Describe briefly the process for finishing with this agent and mention how the reason to the very durable flame retardant finish obtained by this process. (No reaction formulas are requested.) (4p) 8b) Discuss briefly environmental aspects and environmental impact the finishing with the flame retardant mentioned above. 8c) Discuss (very) briefly a theory about the mechanism for the flame retardant function of phosphorous-based flame retardants.

6 Flame retardant agent (question 8) Question 9 (10p) 9a) Describe briefly how the polymer walls of the microcapsules are formed by the two chemical microencapsulation methods, interfacial polymerisation and (complex) coacervation. For the wall formation the following chemicals are used: hexamethylenedisocyanate, HMDI (soluble in cyclohexane), Diethylenetriamine, DETA (water soluble), gelatine, gum Arabic. (7p) (Please note that the full encapsulation procedures are not requested and that no chemical formulas are requested.) 9b) Mention four applications of microcapsules in textiles. Question 10 (10p) 10a) Discuss briefly different aspects of cultivation of GMO cotton (dominating types of GMO cotton, advantages, possible disadvantages/risks). (5p) 10b) What is the Candidate list in the EU legislation concerning chemical substances, REACH and which groups of harmful chemicals are included in the list? 10c) A retailer of textile fabrics delivers fabrics to furniture producers as well as directly to private customers. The fabrics contain a substance (at concentrations of 0,15% of the fabric weight), which is on the REACH Candidate list. Mention what the retailer must do in order to follow the regulations in REACH. (2p)

7 Appendix 1