Advances on concrete strength properties after adding polypropylene fibers from health personal protective equipment (PPE) of COVID-19: Implication on waste management and sustainable environment.

Using Health personal protective equipment (PPE) such as face masks, safety foot shoes and protective suits has expanded dramatically due to COVID-19 pandemic leading to a widespread distribution of the PPE, particularly the face masks, in the environments including streets, dump sites, seashores and other risky locations. The environmental degradation of polypropylene, the essential plastic component in single-use face masks (SUM), takes between 20 and 30 years and thus it is essential to develop experimental approaches to recycle the polypropylene or to reuse it in different ways. This paper explores the integration of SUM into concrete structures to improve its mechanical properties. We first to cut the inner nose wire and ear loops, then distribute the PPE material among five different mixed styles. The PPE were applied by volume at 0%, 1%, 1.5%, 2.0%, and 2.5%, with tests focusing on UCS, STS, FS, and PV to determine the concrete's overall consistency and assess the improvement in its mechanical properties. The results showed that adding PPE improves the strength properties and general performance of the concrete specimens. The pattern of rising intensity started to fade after 2%. The findings demonstrated that adding PPE fibers enhanced the UCS by 9.4% at the optimum 2% PPE. The PPE fibers, on the other side, are crucial in calculating the STS and FS of the reinforcement concrete.

Performance of concrete containing recycled masks used for personal protection during coronavirus pandemic.

After the coronavirus outbreak, a tremendous amount of personal protective equipment has been produced and used by the health service and every human. Proper medical waste management becomes an important problem, which must be solved with a minimal environmental impact. The presented manuscript introduces the recycling process, during which personal protection masks are transformed into polypropylene fibers being an addition to a concrete mixture. The designed recycling procedure provides the entire disinfection of probably contaminated medical wastes, is straightforward, and potentially enables one to modify the properties of the final product. The applied dosage referred to 1 mask per 1 L of concrete. The final product of face masks processing was studied using Fourier-transform infrared spectroscopy, thermogravimetric analysis, surface free energy, contact angle measurements, and melt flow index. The analysis indicated that polypropylene is its main component. Two concrete mixtures were composed, i.e., with the addition of processed masks and the reference one. The following properties were determined to compare the modified concrete with the reference one: compressive and tensile strength, frost resistance, water transport properties, resistance to high temperature. The obtained results indicated that the addition of processed masks slightly increased the compressive strength (by about 5%) and decreased the tensile strength (by about 3%). Simultaneously, it was reported that the addition did not affect material properties related to concrete durability as frost resistance, water permeability, and fire performance. The results evinced, that the addition of processed facemasks into concrete did not deteriorate its properties. Therefore, it is a possible way of the protective masks processing and reusing with the high recycling capacity. Further study should be conducted to optimize the dosing and to modify the properties of PP strings to improve hardened concrete properties.

The recycling of surgical face masks as sound porous absorbers: Preliminary evaluation.

This paper presents the results of an experimental study on the acoustic efficiency of plastic surgical face masks. Since the very high number of disposable masks being used globally on a daily basis to face the Covid19 pandemic is posing new environmental risks, mainly connected to improper disposal, any possible improvements in the management of this waste stream is very important. In this work their potential use as sound porous absorber is discussed. Surgical face masks are mainly made of polypropylene fibers which show good acoustical properties. Their porous structure was studied through the measurement of some non-acoustic properties: bulk density, fiber diameter, porosity, flow resistivity and tortuosity. Moreover, the sound absorption performance of samples, made of scrapped face masks, with different thicknesses was evaluated using an impedance tube according to ISO 10534-2. The results obtained from the sound absorption spectra and two single indexes, Noise Reduction Coefficient and Sound Absorption Average showed a high sound absorption value over a frequency range of interest. Finally, the sound absorption spectra obtained for surgical face masks were compared with those obtained for fibrous materials currently used in building sector, suggesting that this fibrous waste could act as a possible substitute to traditional ones.