SummaryDue to the rising global environment protection awareness, recycling strategies that comply with the circular economy principles are needed. Polyesters are among the most used materials in the textile industry; therefore, achieving a complete poly(ethylene terephthalate) (PET) hydrolysis in an environmentally friendly way is a current challenge. In this work, a chemo‐enzymatic treatment was developed to recover the PET building blocks, namely terephthalic acid (TA) and ethylene glycol. To monitor the monomer and oligomer content in solid samples, a Fourier‐transformed Raman method was successfully developed. A shift of the free carboxylic groups (1632 cm−1) of TA into the deprotonated state (1604 and 1398 cm−1) was observed and bands at 1728 and 1398 cm−1 were used to assess purity of TA after the chemo‐enzymatic PET hydrolysis. The chemical treatment, performed under neutral conditions (T = 250 °C, P = 40 bar), led to conversion of PET into 85% TA and small oligomers. The latter were hydrolysed in a second step using the Humicola insolens cutinase (HiC) yielding 97% pure TA, therefore comparable with the commercial synthesis‐grade TA (98%).

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World is facing numerous environmental challenges, one of them being the increasing pollution both in the atmosphere and landfi lls. After the goods have been used, they are either buried or burnt. Both ways of disposal are detrimental and hazardous to the environment. The term biodegradation is becoming more and more important, as it converts materials into water, carbon dioxide and biomass, which present no harm to the environment. Nowadays, a lot of research is performed on the development of biodegradable polymers, which can "vanish" from the Earth surface after being used. In this respect, this research work was conducted in order to study the biodegradation phenomenon of cellulosic and non-cellulosic textile materials when buried in soil, for them to be used in our daily lives with maximum effi ciency and after their use, to be disposed of easily with no harmful eff ects to the environment. This research indicates the time span of the use life of various cellulosic and non-cellulosic materials such as cotton, jute, linen, fl ax, wool when used for the reinforcement of soil. The visual observations and applied microscopic methods revealed that the biodegradation of cellulose textile materials proceeded in a similar way as for non-cellulosic materials, the only difference being the time of biodegradation. The non-cellulosic textile material (wool) was relatively more resistant to microorganisms due to its molecular structure and surface.

The need for an improved sensor performance is always encouraging us towards exploring new materials. Following the invention of dendrimers, the possibility was recognised of using them for improving optical sensor performance. Their more important aspects are their two main structural properties: three-dimensional structure and multiple terminal functional groups. In this review, firstly a brief introduction to dendrimers is provided with the focus on PAMAM dendrimers and optical sensors. Recent advances have been reported in those PAMAM dendrimer-based optical sensors, which are used for the detection of pH, cations, and other analyte.

A new circular economy concept is presented for the textile sector to convert unwearable polyester textile waste into valuable chemical feedstock. The idea behind it is to develop a new circular economy concept for the most used material in the textile industry, that is, polyester. Hydrothermal hydrolysis, an environmentally friendly process, has been studied for recovering polyester monomeric units. Under high-temperature and high-pressure conditions complete chemical depolymerization of pure poly(ethylene terephthalate) (PET) to terephthalic acid (TPA) was achieved at high yield. The produced TPA was characterized by potentiometric titrations, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and elemental analysis. A series of experiments were performed on the PET material with different intrinsic viscosities to define the appropriate depolymerization conditions related to the temperature ( T), time ( t) and PET:H2O ratio, which enables total conversion of the polymer. Maximal conversion (92%) to TPA was defined at 250℃, pressure of 39–40 bar, PET:water ratio of 1:10 and hydrolysis time of 30 min after reaching steady-state conditions in the reactor. The applied depolymerization route resulted in moderate purity of the originated TPA, which was applied successfully in a laboratory-scale two-step re-polymerization to produce PET resins.

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The aim of this research was to develop the formulation of chitosan in combination with honey in different mass proportions of each of the components within the separate mixture. Such a formulation could serve as a functional coating suitable for wound healing. From the perspective of different formulations used within research presented, it is assumed that the different mass fraction of components will affect antimicrobial and antioxidant activity of the functionalised substrate differently. To apply the separate formulation onto a non-woven viscose substrate, the conventional pad-drying process was selected. Moreover a study of the effectiveness of the individual treatment was performed systematically, which is also reflected in the systematics of the experimental techniques selected. Considering antioxidant and antimicrobial action, honey-functionalised non-woven viscose shows higher effectiveness if compared to non-woven viscose functionalized with the chitosan:honey combination.