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Research is described in the article concerning the melt processing of biodegradable aliphatic-aromatic copolyesters into fibrous products. Copolyesters containing 57 -60% of a tri-component aliphatic portion (copolymers of butylene glycol and adypic-, succinic-, glutaric acid and terephtalic acid) prepared on a large laboratory scale were used in fibres and nonwoven from molten polymers. Fibres were made in a two-step process comprising spinning and drawing. Nonwovens were formed by the spunbond method. Main properties are given of the polymers and fibres, and the nonwoven made thereof. It was found that the aliphatic-aromatic copolyesters prepared reveal good spinability. Thermal properties: T g < 0 °C and low T m ~115 °C of fibres made of aliphatic-aromatic copolyesters limit their possible uses mainly to the production of disposables. A cheap method of making spunbond nonwoven which leads to ready textiles is recommended for the processing of the copolyesters.

Abstract:The problem of incorporating plastics into the environment will be aggravating, both regarding its scale and kind of these materials. Investigations were carried out using aliphatic-aromatic copolyester poly (succinate-co-glutarate-co-adipate-co-terephthalate 1,4-butylene) with addition of fatty acid dimers. The work aimed to determine the effect of composting the copolyester with plant biomass on changes of fractional composition of humus substances and their stability. Copolyester was supplemented to the biomass in the form of a nonwoven fabric in two doses. It constituted 8 and 16% of the dry mass of the composted substrates. The composting process was run within two ranges of ambient temperature 25-30°C and 40-45°C. After the completion of this process, the degree of material maturing was assessed using manometric methods and the carbon content was analysed in the individual organic matter fractions. On the basis of cumulated respiratory activity AT4 a lack of composted material activity was revealed in the higher temperatures of the process. However, in the objects where copolyester was transformed in the lower temperatures this activity was considerably diversified. Adding copolyester to the composted biomass led to a diversification of the Cha : Cfa ratio. The values of Cha : Cfa ratio most approximating 1.5, ie the value regarded as optimal, were registered in the object, where copolyester supplement constituted 16% and the plant biomass was maintained within the 40-45°C temperature range.

Textile materials, because of their specific character, can affect the content of volatile pollutants in the indoor air, including the constituents of tobacco smoke (ETS-environmental tobacco smoke). Polypropylene fibers have a particularly high susceptibility for the sorption of nicotine. Textiles made of polypropylene are often used in different rooms or offices. The aim of the research was to give polypropylene fibers the photocatalytic properties by modifying their surface, using titanium dioxide doped with nanoparticles of silver (TiO 2 /Ag). Modification of polypropylene fibers with TiO 2 /Ag increases their susceptibility to sorption of nicotine and accelerates its decomposition. A comparison of the decomposition rate constants for the modified and unmodified fibers shows that the decomposition process runs from 1.6 to 2.9 times faster for the modified fibers depending on the nature of modification, the source of the nicotine and the ambient conditions. It was also found that the strength of modified fibers does not change under irradiation.