Paper is present in almost every aspect of our lives. From packaging for food and medicine, through office supplies to various uses in industry and construction - this is one of the most multifunctional and susceptible to modification materials. Although it is increasingly said that paper books will be supplanted by ebooks, and archives move their collections to the Internet, one cannot overestimate how much we need paper in other industries.
Therefore, the great news is that scientists from the Faculty of Chemistry of the Jagiellonian University are currently working on improving a new multifunctional cellulose paper with a filler enriched with silver ions. The idea of adding a filler with sorptive properties to the pulp is nothing new - cellulose fibers help bind and hold the filler particles. The new invention, however, is distinguished by adding silver ions to the filler, thanks to which the material gained additional features.
What are the properties of the new material? First of all, its basis is still pulp, which makes it, like ordinary paper, easy and cheap to obtain in large quantities. The pulp can also be formed into two- and three-dimensional shapes, as well as dried (the possibility of blowing into insulated spaces) or suspended in a liquid (then it can be applied in the form of a spray). The filler - in this case the Y type zeolite - is responsible for the sorption properties of the material. It absorbs gaseous pollutants - sulfur and nitrogen oxides, as well as volatile organic compounds and unpleasant odors - arising, for example, as a result of the decomposition of organic matter.
The addition of silver ions to the filler means that the gases can be removed not only by sorption, but also by catalytic decomposition. Due to the presence of silver, this paper also has biostatic and biocidal properties. Microbiological studies have shown that it is effective in inhibiting the growth of a number of bacteria (such as E. coli or B. subtilis) and fungi (including A. niger, C. cladosporioides). Importantly, researchers also developed a method to eliminate silver in unbound form, which prevents the problem of ion migration. As a result, the risk of pollution of the environment or of packaged silver products is almost completely reduced. It is also important that the synthesis of material components uses the latest methods and principles of so-called green chemistry, so the process consists of only a few steps, is based on water and a small number of reagents, and as a result no waste that is burdensome to utilize.
Where can we use this new material? Of course, in the paper industry itself, where it could be used to create packaging, folders, envelopes and packaging for archival materials, but not only. This type of paper could be used to protect monuments and works of art (also organic). As we are already securing, packaging or spray from this material could help preserve freshness of cut flowers and seeds for longer. In this type of packaging you could pack herbal, pharmaceutical and medicine preparations, as well as food products, affecting their best before dates. Thanks to the sorption and biocidal properties of the material, it will be useful wherever odors arise - for example in the veterinary industry, to create materials lining cages and foundations to remove odors, as well as bags for dog droppings. The material could also be used to create shoe pads or toilet materials, and on a slightly larger scale insulating spray coatings and blown insulations used in construction.
The invention is covered by a patent. The CITTRU Technology Transfer Center of the Jagiellonian University is looking for entities interested in obtaining a license for the material described and its application. Partners interested in further research and development projects covering this subject are also sought.
Author: Katarzyna Nowacka