Search Results (4)

Straw has been used as a building material since time immemorial and has been considered as a waste product from the agricultural sector, usually used for feed, bedding, or fertilization. Nowadays, the construction industry strives to reduce greenhouse gas emissions and is focusing on renewable materials; hence, straw seems to be an attractive, low-energy option. Straw bales or blown insulation are common uses, with limited detailed knowledge regarding the properties of different straw types. Straw is made up of the dry stems of crops. Straw’s chemical composition will differ with different crops and can have a great impact on its effectiveness. As a renewable material, straw also has the potential to be used in buildings, enhancing thermal insulation and reducing environmental impacts. This study considers four kinds of straw: barley, oats, oilseed rape, and triticale, regarding their possible usage in insulation materials. The thermal conductivity, bulk density, and dust generation of each type were tested in the laboratory. Among them, the best performance was shown by the barley straw treated with mechanical pulping using a knife mill at 4000 rpm for 60 s, which showed the lowest bulk density and thermal conductivity and generated the least dust. It is thus proven to be an environmental insulation material with significant implications for sustainable construction and energy-efficient building design, further helping in maintaining environmental sustainability in building construction. Full article

In recent years, due to environmental awareness regarding the harmfulness of polymeric materials, there has been a growing interest in using papers, especially those from alternative raw materials. The importance of using all available raw materials is imperative today. Raw materials that were once viewed as waste are now of great importance because they have the ability to replace raw materials that are used irrationally or are lacking. Cereal straw is a lignocellulosic material that could be used in the paper industry and in the production of increasingly prevalent paper packaging. The aim of this research was to analyze the relationships between the qualitative parameters of straw-based printed papers containing 30% agricultural residues (wheat, barley, or triticale). The influence of two qualitative parameters (ink penetration depth and optical ink density) on the print-through was observed using multiple regression analysis on straw-based papers produced at the laboratory level. Throughout the research, 100% recycled wood paper was used as a reference sample. The results of the regression analysis showed that none of the variables individually make a statistically significant contribution to the prediction of the dependent variable in a linear context, that is, they indicate a non-linear interaction between the variables and the specific conditions under which the dependent variable reaches local extremes and changes in the gradient. Considering the results of the regression analysis and the visualization of the relationship, the model was additionally tested with other independent variables (paper type). From the results obtained, it can be concluded that the alternative straw-based paper with 30% barley pulp has the best interaction between ink and paper, which is the most similar to the reference sample in terms of printability, while the alternative straw-based paper with 30% wheat generally differs significantly from the reference paper when all three prints are considered. Full article

The suitability of industrial hemp (IH) as a source of fibres for European industrial-scale papermaking, including, in particular, European kraft pulp mills (EKMPs) (i.e., plants producing the predominant amount of virgin pulps in Europe), was discussed, considering the causal, cultivation, technological, and application aspects of this issue. The work showed that there are generally premises for using straw from nonwood crops in European papermaking. As for the IH, it was found that IH stalks are the best IH fibrous raw material for EKMPs. There are a few cultivation factors favouring the use of IH stalks in them and a few, though important (e.g., small cultivation areas), factors not conducive to this use. Most technological factors favour the use of IH stalks in EKPMs, apart from the large differences in the length of the IH bast and woody-core fibres. The analysis of application factors indicates lower usefulness of IH stalks than wheat, rye or triticale straws, stalks of Miscanthus × giganteus, Virginia mallow, and kenaf. This is due to the much greater availability of these cereal straws than IH and less variation in the fibre length of cereal straws, Miscanthus × giganteus, Virginia mallow, and kenaf than in IH stalks. The main conclusion from the conducted query is the statement that the presence of IH varieties with fibre lengths more similar to wood would reduce the number of technological and application factors unfavourable to their use in EKPMs and increase the competitiveness of hemp straw vs. wood as a raw material for European large-scale papermaking. Full article

Due to the rising problem of deforestation, slow renewability, and higher cost of wood sources, it is of great importance for the paper and packaging industry to find suitable, environmentally friendly alternative sources of cellulose fibers. Much of the research has focused on studying the use of non-wood sources from various annual or perennial plants from which cellulose fibers can be obtained with equal quality to those from wood sources, since they are a fast-growing, renewable, and cheap source of fibers. This research focuses on the laboratory production and stability valorization of a paper substrate for packaging containing virgin fibers from triticale straw mixed with recycled wood pulp in various amounts up to 30%, printed with black ink through a simulation of the offset printing technique under controlled conditions. For stability analysis, printed paper substrates were subjected to three treatments essential for packaging: aging, rubbing, and chemical treatment. The stability of the prints was evaluated after treatments though spectrophotometric measurements (ΔE*_ab, ΔR, ΔL*, Δa*, Δb*) and Fourier transform infrared analysis. The aging, rubbing, and chemical stability of the prints with the addition of triticale virgin fibers was improved for all product packaging except for products containing soybean oil. Full article