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The COVID-19 epidemic surprised economic operators around the world. The very existence of many businesses, and thus jobs, was at stake. However, one year after the WHO declared the outbreak a pandemic, contrary to the pessimistic forecasts of business analysts, some industries did not experience the predicted negative effects of the crisis. This article presents the results of a pilot study on micro and small enterprises in the rubber products industry in Poland during the COVID-19 pandemic, with the aim of analyzing the phenomenon of sustainable resource management that led not only to the survival of these enterprises but also to a significant increase in their turnover. Therefore, the purpose of the study was to analyze the key success factors of the indicated economic entities, with particular emphasis on the perspective of sustainable resource management and relationship management. On the basis of best research practices, a triangulation of research methods was applied (integrative literature review, computer-assisted telephone interviewing, and individual in-depth interview). A relationship was observed between the sustainable management of resources and the structure of the relationship network and the strength of its connections. In micro and small enterprises in the rubber products sector in Poland, sustainable resource management is related to the structure of the network of relations and the strength of connections in the network (relations/networking), as enterprises form a group of entities with a high level of loyalty, especially between the suppliers and buyers of raw materials. The formulated conclusions will become the basis for further in-depth research that can be conducted (a) in the same group of respondents, but using a representative research group, (b) in the same industry among a group of large enterprises, and (c) in a group of small and medium-sized enterprises (SMEs) from other industries.

Summary Natural rubber (NR) is a nonfungible and valuable biopolymer, used to manufacture ~50 000 rubber products, including tires and medical gloves. Current production of NR is derived entirely from the para rubber tree (Hevea brasiliensis). The increasing demand for NR, coupled with limitations and vulnerability of H. brasiliensis production systems, has induced increasing interest among scientists and companies in potential alternative NR crops. Genetic/metabolic pathway engineering approaches, to generate NR‐enriched genotypes of alternative NR plants, are of great importance. However, although our knowledge of rubber biochemistry has significantly advanced, our current understanding of NR biosynthesis, the biosynthetic machinery and the molecular mechanisms involved remains incomplete. Two spatially separated metabolic pathways provide precursors for NR biosynthesis in plants and their genes and enzymes/complexes are quite well understood. In contrast, understanding of the proteins and genes involved in the final step(s)—the synthesis of the high molecular weight rubber polymer itself—is only now beginning to emerge. In this review, we provide a critical evaluation of recent research developments in NR biosynthesis, in vitro reconstitution, and the genetic and metabolic pathway engineering advances intended to improve NR content in plants, including H. brasiliensis, two other prospective alternative rubber crops, namely the rubber dandelion and guayule, and model species, such as lettuce. We describe a new model of the rubber transferase complex, which integrates these developments. In addition, we highlight the current challenges in NR biosynthesis research and future perspectives on metabolic pathway engineering of NR to speed alternative rubber crop commercial development.

Rubber is an essential part of our daily lives with thousands of rubber-based products being made and used. Natural rubber undergoes chemical processes and structural modifications, while synthetic rubber, mainly synthetized from petroleum by-products are difficult to degrade safely and sustainably. The most prominent group of biological rubber degraders are Actinobacteria. Rubber degrading Actinobacteria contain rubber degrading genes or rubber oxygenase known as latex clearing protein (lcp). Rubber is a polymer consisting of isoprene, each containing one double bond. The degradation of rubber first takes place when lcp enzyme cleaves the isoprene double bond, breaking them down into the sole carbon and energy source to be utilized by the bacteria. Actinobacteria grow in diverse environments, and lcp gene containing strains have been detected from various sources including soil, water, human, animal, and plant samples. This review entails the occurrence, physiology, biochemistry, and molecular characteristics of Actinobacteria with respect to its rubber degrading ability, and discusses possible technological applications based on the activity of Actinobacteria for treating rubber waste in a more environmentally responsible manner.

Antioxidants are prevalently used during rubber production to improve rubber performance, delay aging, and extend service life. However, recent studies have revealed that their transformation products (TPs) could adversely affect environmental organisms and even lead to environmental events, which led to great public concern about environmental occurrence and potential impacts of rubber antioxidants and their TPs. In this review, we first summarize the category and application of rubber antioxidants in the world, and then demonstrate the formation mechanism of their TPs in the environment, emphasizing their influence on the ozone oxidative degradation. The potential toxic effects of antioxidants and their TPs are further reviewed to improve understanding of their biological health impact and environmental risks. Finally, the environmental occurrences of antioxidants and their TPs are summarized and their environmental impacts are demonstrated based on the recent studies. Due to the currently limited understanding on the toxic and biological effects of these compounds, further studies are required in order to better assess various TPs of these antioxidants and their environmental impact. To our knowledge, this is the first review on antioxidants and their TPs in the environment, which may elevate the environmental risk awareness of rubber products and their TPs in the near future.

Waste tires are known as “black pollution”, which is difficult to degrade. The safe handling and recycling of waste tires have always been the focus of and difficulty for the global rubber industry. Pyrolysis can not only solve the problem of environmental pollution but also completely treat the waste tires and recover valuable pyrolysis products. This paper summarizes research progress on the pyrolysis of waste tires, including the pyrolysis mechanism; the important factors affecting the pyrolysis of waste tires (pyrolysis temperature and catalysts); and the composition, properties, and applications of the three kinds of pyrolysis products. The composition and yield of pyrolysis products can be regulated by pyrolysis temperature and catalysts, and pyrolysis products can be well used in many industrial occasions after different forms of post-treatment.

Production of rubber products with biobased constituents from biomass resources is desirable for conserving our planet’s limited resources and preventing global warming. Herein, a natural rubber model compound was produced to determine the biobased contents as per various indices for calculating the amount of biomass resources used in rubber products. The biobased mass and biobased carbon contents of the natural rubber model compound were 38.7% and 39.2%, respectively, which were calculated from the feed amounts of the constituents as per the International Organization for Standardization (ISO)/the draft of International Standard (DIS) 16620-2 and 16620-4. The model compound was separated into its constituents such as polymer, additive, carbon black, and zinc oxide using ISO 1407, 4650, 7720-2, and 9924-3. The biobased carbon content of this model compound was 37.6%, calculated from the percent of modern carbon (pMC), which was measured directly using accelerator mass spectrometry (AMS). The calculated values for this model compound agreed with those calculated from the feed amounts of the constituents. Thus, it was confirmed that these calculation and determination methods of the biobased mass and the biobased carbon contents for rubber products should be published as new ISO international standards after a discussion at technical committee 45, “rubber and rubber products” to evaluate rubber products with larger biobased contents of natural rubber and other biobased ingredients.

Tire rubber recycling for civil engineering applications and products is developing faster, achieving increasingly higher levels of maturation. The improvements in the material circle, where crumb rubber, generated as a by-product of the tire rubber making process, becomes the resource used for the construction of road asphalt pavement, is absolutely necessary for increasing the sustainability of the entire supply chain. The paper reports the results of an accurate data analysis derived from an extensive literature review of existing processes, technologies, and materials within construction of infrastructure. The current position, the direction, and rate of progress of the scientific efforts towards the reuse and recycling of tire rubber worldwide have been shown. Furthermore, an in-depth analysis of a set of important properties of Crumb Rubber Modified Asphalt has been carried out—fabrication parameters, standard properties, high and low-temperature performance, and rheological properties. Statistics over a sample of selected publications have been presented to understand the main processes adopted, rubber particle size, temperatures, and possible further modifications of crumb rubber modified binder.

The hand endows us with unparalleled precision and versatility in our interactions with objects, from mundane activities such as grasping to extraordinary ones such as virtuoso pianism. The complex anatomy of the human hand combined with expansive and specialized neuronal control circuits allows a wide range of precise manual behaviours. To support these behaviours, an exquisite sensory apparatus, spanning the modalities of touch and proprioception, conveys detailed and timely information about our interactions with objects and about the objects themselves. The study of manual dexterity provides a unique lens into the sensorimotor mechanisms that endow the nervous system with the ability to flexibly generate complex behaviour.Hands enable us to interact with objects in precise and versatile ways. In this Review, Sobinov and Bensmaia discuss aspects of mundane and expert manual behaviours, the anatomical complexity of the human hand and neural mechanisms that underlie manual dexterity.

Recently, minimizing petroleum resources as well as safely disposing of agro-wastes are essential for the production process to comply with environmental legislation. Bio-filler as an alternative to non-safety carbon black (CB) from petroleum resources in the production of rubber composites is investigated by many researchers, but unfortunately it leads to deterioration of the properties of rubber composites. To avoid this drawback, different agro-wastes (rice straw, date palm fiber, and reed ( Arundo donax L.) with different chemical constituents as precursors of biofillers (biochars) are assessed toward the performance of ethylene-propylene-diene terpolymer rubber (EPDM). The role of replacing parts of CB with biochar on the rheological characteristics, physico-mechanical properties, hardness, swelling, and crosslinking density of EPDM composites is studied. The results proved the efficient low replacing ratio of biochar towards increasing the minimum and maximum torque; this indicates a homogeneous filler structure and crosslinking interactions between the components matrix as emphasized from the morphological analysis of EPDM rubber. The reverse trend is noticed on increasing the replacement ratio over 25%, where it deteriorates the tensile strength in comparison to pristine CB. The data demonstrated the most efficient biochar, which is derived from RS. The formulation containing 75% CB and 25% RS-biochar provided EPDM with tensile strength (14.4 MPa), higher than the pure CB (12.45 MPa). Moreover, this optimum formulation provided high crosslinking density, high hardness shore A, and swelling resistance of motor oil and toluene when compared to EPDM with pure carbon black. This promising finding trend is not noticed in the literature on using biochars, which usually caused the deterioration in properties of rubber products.

The use of a circular economy (CE) in a supply chain is conducive to remanufacturing. It can not only make the supply chain innovative but can also further ease resource consumption and lower pollution, thereby reducing carbon emissions. However, most current research remains focused on the concept of integrating circular economy supply chains (CESCs); few studies have carried out practical research in industry, and research addressing issues regarding the rubber recycling industry is even rarer. Therefore, this study refined the existing framework by screening out key factors that a CESC applies to remanufacturing products. This study conducted an expert questionnaire survey using the FDM to select key factors. Since the 30 respondents selected for this study are all experts in related fields, the reliability and stability of the method and results can be ensured. Meanwhile, this study adopted the fuzzy DEMATEL method to rank the importance of the five selected aspects and nineteen criteria and clarified cause-and-effect relationships between the criteria. The results show that important aspects, including “the circular business model” and “enhancing the resource value in the supply chain”, are both classified as cause groups; there are four main criteria that need to be highlighted, namely, “optimizing the production process”, “effectively tracking and recycling products”, “redesigning remanufactured rubber products”, and “improving resource efficiency”. Therefore, when related industries build CESCs to manufacture remanufactured products, these criteria need to be considered first. This study combined a CESC with remanufactured products, constructed a new framework to expand the related literature, and further analyzed the rubber industry and the underlying rubber recycling industry. Accordingly, related industries can refer to the new framework and key factors to develop production strategies for remanufactured products when implementing a CESC.