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Packaging materials can arise from a wide range of sources and are commonly used for food, medicine, household appliances, and items to enclose or protect products during distribution, storage, sale, delivery, and use. The choice of material (paper, plastic, glass, wood, metal, multi-layer or other packaging) to be used depends on the type and properties of product, the purpose of packaging, and the price. The aim of the investigation is to analyse the morphological composition of packaging waste collected separately in Kaunas (Lithuanian) private households and to evaluate its recycling possibilities. The mixture of paper, plastic, and metal packaging waste was analyzed in the winter and spring (one time per month) in the waste management company JSC "Kauno švara".

Background. The development of technologies for obtaining materials from plant raw materials, the use of which improves the consumer properties of cardboard and paper products and does not pollute the environment with harmful substances from synthetic polymers, is an urgent problem of our time. Objective. The purpose of the paper is to obtain pulp and nanocellulose from reed stalks by environmentally friendly methods and apply nanocellulose to improve the quality parameters of paper for packaging food products on automatic machines. Methods. To obtain pulp from reed stalks with a minimum residual content of lignin and minerals, two processing stages were used: alkaline extraction and organosolv cooking at a temperature of 97 ± 2 °C. Nanocellulose was obtained by the oxidation of organosolv reed pulp with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) in the TEMPO / NaBr / NaClO system, which is more environmentally friendly than acid hydrolysis. The resulting nanocellulose was applied to paper samples from waste paper and sulphate unbleached pulp at a consumption from 1 to 3 g/m2. Results. Organosolv pulp was obtained from reed stalks with a residual lignin content of 0.53 % and an ash content of 0.045 %, which was used to obtain nanocellulose. The resulting nanocellulose particles have a transverse size in the range of 5–20 nm, a length of up to several micrometers, and the tensile strength of nanocellulose films is up to 60 MPa. It is shown that the application of nanocellulose to the surface of the samples increases the breaking strength and breaking length, and reduces the surface absorbency of paper. It was determined that with a nanocellulose consumption of up to 3 g/m2, paper samples have indicators that meet the requirements of the standard for paper for packaging food products on automatic machines. Conclusions. The use of nanocellulose from reed stalks as a hardening substance for paper production will allow replacing environmentally harmful polymer additives and up to 50 % of more expensive softwood pulp with waste paper, while maintaining paper quality indicators at the level of standard requirements.

The objective a study of the aging processes of library documents on various types of paper that have been in an emergency compared to documents that have not experienced a negative technological load. The research methodology consists in the application of instrumental, mathematical and applied methods, which allows to most fully reveal the tasks and prospects of further storage of documents on traditional media that have undergone negative environmental influences. The scientific novelty of the work is to expand ideas about the features of long-term storage of documents on traditional media that have been in extreme conditions. For the experiments, the types of paper that were used as the material basis of the documents subjected to the greatest extreme technogenic load - excessive wetting, freezing, and drying -- were selected as model samples. This is rag paper of the 17th - 18th centuries, newsprint of the middle of the 20th century, printing paper No. 1 of the middle of the 20th century. with certain physicochemical and capillary hygroscopic properties. The operational properties of these model paper samples were determined by mechanical strength indicators: fracture strength at repeated kinks, destructive force and tensile strength, because it is these indicators that most accurately characterize the processes of natural aging of the material. Conclusion. Providing targeted recommendations for categories of documents on traditional media that have undergone anthropogenic load depending on the type of paper, the degree and nature of the impact of negative factors in an emergency. Also relevant are ways of protecting binding materials in an emergency, because the frame is often the first to experience the consequences of its negative impact. For a positive solution to the problem of ensuring the safety of documents on traditional media that have undergone anthropogenic load, it remains relevant to implement all possible varieties of preventive conservation as a guarantee of the effective safety of library collections. [ABSTRACT FROM AUTHOR]

Background. Development of technology for obtaining peracetic pulp from oat straw and its use in the production of one of the paper mass types. Objective. Determination of peracetic cooking technological parameters’ optimal values for oat straw peracetic cellulose quality indicators. Methods. The oat straw cooking was carried out with peracetic acid at 95 ± 1 °C from 90 to 180 min for hydromodulus 8:1 and 7:1, using a sodium tungstate catalyst. To determine the oat straw peracetic cellulose mechanical indexes, laboratory samples of paper weighing 70 g/m2 were made. Results. Technological parameters’ optimum values (temperature, cooking duration, hydromodulus, hydrogen peroxide and acetic acid concentration) for the oat straw delignification process were established. It is shown that the sodium tungstate catalyst addition to the cooking solution at a rate of up to 1 % of the plant raw material weight helps to reduce the lignin content in cellulose to 15 %. A diagram of the cellulose yield dependence on its residual lignin content for various methods of non-wood plant material species delignification is constructed. The high efficiency of the peracetic method for obtaining cellulose from non-wood plant raw materials, in particular from oat straw, has been confirmed. It is determined that the obtained peracetic cellulose from oat straw has high mechanical indexes. Conclusions. Oat straw peracetic cellulose can be used for the production of paper and cardboard mass types, in particular wrapping paper.

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