The objective of this project was to develop blends based upon post consumer RPET and N6, and to evaluate the suitability of these blends to form fibres for the end use in carpet fibre. In the work carried out it was found it is possible to spin RPET/N6 biconstituent fibres over a wide range of blend ratios. All the blends studied have diminished physical properties when compared to those of pure RPET and N6. The processability of these blends also deteriorated due to the large increases in normal forces which manifests in extrusion equipment as die swell that often results in melt fracture. It has been shown that the morphology of the fibre controls the degree of decay in properties and die swell at the spinnerette. The blends that are rich in one phase, with the secondary phase distributed as elongated fibrils have shown better physical performance and improved processing compared to the blends 70/30 � 30/70, which have poorer properties and increased die swell due to there co-continuous morphology. In quiescent studies, the physical properties of the blends have had little deviation from those predicted using a rule of mixtures line. In and around the 50% RPET blend, die swell was observed to be extreme and this makes fibre spinning difficult. It was found that this was caused by a loss in viscosity in the blends and a general increase in normal forces in response to applied shear. The die swell phenomenon is a rheological characteristic of the blends, which was inevitably caused by internal capillary flow of one component in the other. IR spectroscopy has shown that there is little to no in-situ compatibilisation occurring during simple melt processing. However, it was found that significant interfacial compatibilisation could be achieved through solid stating N6/RPET blends. The FTIR spectra for solid state blends in figure 4.51 has shown absorbency in the 3300 cm-1 region after all free N6 was removed. This indicates that in-situ compatibilisation has occurred between the phases in the solid stating process and it is a time dependent reaction. The Burgers and Koltunov models can be used to predict the creep behaviour of the fibre blends studied. The Burgers model provides greater accuracy for longer-term exposure to stress. From the thermal results, the solid stating process significantly affects the melting and crystallisation out of the melt and the ultimate level of crystallinity. The contribution of the copolymer in these changes appears to be small. The physical strength of the fibres made on the laboratory line was only marginally lower than those made on a factory line. The morphology of the mid-range blends is co-continuous and that of the N6 and RPET rich blends is dispersed droplet morphology. Based on the finding, a N6 rich blends and in particular the 10% RPET blend is the most suitable for further commercial development as its processing, physical performance and post spinning processing closely resemble the pure N6 currently in use. It has provided performance and consistency throughout the processing and testing we have conducted.

Textilindustrin är den mest förorenande industrin efter oljeindustrin och ett mål är därför att arbeta med mer återvunna fibrer. Dock väljs ofta dessa alternativ bort av konsumenter även fast en viss efterfrågan har identifierats. Trots en ökad efterfrågan kopplat till hållbara val så besitter inte konsumenter kunskap kring miljöfrågor kopplade till de hållbara alternativen. Avsaknad av kunskap kan alltså vara en orsak till varför deras åsikter inte återspeglas i konsumtionsvalet, därmed uppstår frågan om det finns ett samband mellan kunskap och köpintentioner, eller vilka variabler som påverkar köpintentioner. Polyester är ett material som är mycket påfrestande för miljön och fortsätter vara populärt att använda. Detta har lett till föroreningar, ett avsevärt ökat utsläpp samt stora mängder PET-avfall till miljön. Produktionen av återvunnen polyester, rPET, är mer miljövänlig än produktion av nyproducerad polyester. Exempelvis, för varje kilo mekanisk återvunnen polyester minskar utsläpp av växthusgaser med 70% jämfört med växthusgasutsläpp orsakade av nyproducerad polyester. Då tidigare studier som använt sig av en omarbetad version av teorin Theory of Planned Behavior har visat att attityder, subjektiva normer, upplevd beteendekontroll samt kunskap påverkar intentioner testar denna studie om så även är fallet när de kommer till köpintentioner till rPET. Genom en kvantitativ enkätundersökning och med hjälp av en omarbetad version av teorin Theory of Planned Behavior undersöks om det finns ett samband mellan modellens variabler och köpintentioner till rPET. Resultatet visar att attityder och upplevd beteendekontroll har ett starkt samband med köpintentioner till rPET samt att det finns ett samband, dock negativt och svagare, mellan objektiv kunskap och köpintentioner till rPET. De andra variablerna, subjektiva normer och subjektiv kunskap, besitter inte ett signifikant samband med köpintentioner till rPET. Fortsättningsvis skiljde sig sambanden för variablerna mellan män och kvinnor. / The textile industry is the most polluting industry after the oil industry. Therefore, a goal is to work with more recycled fibers within the textile industry. However, these alternatives are often opted out by consumers despite the fact that a demand has been identified on the market. Previous studies have shown that even though the increased demand is associated with sustainable choices, consumers do not possess knowledge about the environmental issues related to sustainable alternatives. Lack of knowledge can be a reason for why consumers' opinions do not reflect on their consumption choices, hence the question arises whether there is a connection between knowledge and purchase intentions, or which variables do affect the purchase intention. Polyester has a negative impact on the environment but remains popular to use. This has led to pollution, significant increase of emissions, and large amounts of PET waste. The production of recycled polyester, rPET, is however more environmentally friendly than the one of newly produced polyester. For instance, for every kilogram of mechanically recycled polyester, the greenhouse gas emissions are reduced by 70% compared to the greenhouse gas emissions caused by newly produced polyester. By using the revised model Theory of Planned Behavior, previous studies have shown that attitudes, subjective norms, perceived behavioral control and knowledge affects intentions. Thus, this study aims to test whether this is the case or not when it comes to purchasing intention for rPET. By using a quantitative survey and a revised version of the model Theory of Planned Behavior, the revised model explores whether there is a relation between these variables and purchasing intentions towards rPET. The results show that attitudes and perceived behavioral control have a strong relation with purchasing intentions to rPET. Moreover, there is a relation, although negative and weaker, between objective knowledge and purchasing intentions to rPET. However the other variables, subjective norms and subjective knowledge, do not have a significant relation with purchasing intentions to rPET. Furthermore, the relation between the variables differ between the genders.

Packaging Materials account for 31% of the world’s municipal solid waste. Agencies like the Environmental Protection Agency (EPA) and the Agency for Toxic Substances and Disease Registry (ATSDR) are pushing for the increased use of recycled thermoplastic materials. Polyethylene terephthalate (PET) is a commonly recycled thermoplastic which is used to package ready-to-eat fruits and vegetables. Most recycled polyethylene terephthalate (RPET) packaging materials contain heavy metal catalysts, the most common being antimony. The recent increased use of recycled plastic materials has been suspected as the source of increased human heavy metal exposure. In this study, cadmium, chromium, nickel, lead and antimony were quantified in post-consumer RPET rigid containers and films using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Two hundred samples were tested of which 29 were found to be contaminated with heavy metals in the parts-per-million (ppm) range. Chromium was found in all the contaminated sample replicates at an average level of 8.18 ppm. Cadmium was found in all the contaminated samples as well. Lead was found in 90.4% of the contaminated samples and concentrations ranged from a low of 0.02 ppm to a high of 0.36 ppm. Nickel was found in 96.4% of the contaminated samples while antimony was found in 97.6% of the samples. Due to limited sample material, 22 of the 29 contaminated RPET rigid containers and films were tested for heavy metal migration into a 5% citric acid:water solution (w/v) or deionized water. Samples were subjected to prolonged storage at 7.2 or 22.2°C for 1, 7 or 14 days, or were exposed for 5 minutes to microwaves from a 1700-watt microwave oven set to 70% power before analysis. Leachate values were at ppb levels but were often below the ICP-AES Limits of Detection which were at also the ppb level, whether calculated for deionized water or 5% citric acid in water. No measureable levels of heavy metal were detected for any sample exposed to water, regardless of treatment. For samples exposed to 5% citrate and stored or microwaved, only chromium and nickel leached at measurable levels, and the number of RPET’s releasing measurable chromium and nickel increased with microwaving compared to the same plastics stored at 22.2 or 7.2°C. Since leaching was calculated as µg/L of heavy metal lost from the entire inner surface (1021 cm2) of a retail salad bag, actual exposure to heavy metal would be much less than measured in this study as retail fruit and vegetable packages and microwaveable pouches usually contain very little liquid in order to increase food safety. The results therefore suggest the potential for little migration of heavy metal from recycled PET to whole or fresh-cut fruits and vegetables when held at ambient or refrigerated temperatures, or when microwaved.