Carlos Mario Gutiérrez-Aguilar

The substantial waste generated during the processing of hides and skins as well as at other stages of manufacturing is a recurring issue in the leather industry that this article attempts to address. To investigate the mechanical and thermal characteristics of the resultant composites, this study suggests using leather waste from the bovine leather industry, analyzes the tanning process, and assesses the viability of mixing this waste with natural rubber (TSR-20). Without the inclusion of leather waste, the resulting composites had exceptional tensile strength, surpassing 100% of rubber’s strength. The effective interaction of the recycled leather particles with the natural rubber matrix was evidenced using the Lorentz–Park equation. This better performance points to a competitive relationship between rubber and leather waste. The samples’ density was 10% greater than that of polybutadiene elastomers and 10% greater than that of natural leather, while the hardness was comparable to that of PVC, which is frequently utilized in the design of general-purpose soles. This suggests that waste from the leather industry can be efficiently utilized in sustainable applications, particularly in the production of leather goods and shoes, helping to valorize waste that is typically discarded. Furthermore, by encouraging the use of recycled resources in the creation of new compounds, this plan provides the rubber sector with a sustainable option. To optimize this proposal, perhaps will be necessary to identify different vulcanization systems to improve the physical mechanical properties and other uses derived from the optimizations realized. This composite can be applied in the fashion industry in order to develop new trends around the application of waste and residues for a natural design line. Through the research process, it was possible to integrate the residues into the natural rubber matrix, as evidenced in the characterization process.

Nowadays, biocomposites represent a new generation of materials that are environmentally friendly, cost-effective, low-density, and not derived from petroleum. They have been widely used to protect the environment and generate new alternatives in the polymer industry. In this study, we incorporated untreated jute fibers (UJFs) and alkaline-treated jute fibers (TJFs) at 1–5 and 10 phr into TSR 10 natural rubber as reinforcement fillers. These composites were produced to be used in countersole shoes manufacturing. Untreated fibers were compared to those treated with 10% sodium hydroxide. The alkali treatment allowed the incorporation of fibers without compromising their mechanical properties. The TJF samples exhibited 8% less hardness, 70% more tensile strength, and the same flexibility compared to their pure rubber counterparts. Thanks to their properties and ergonomic appearance, the composites obtained here can be useful in many applications: construction materials (sound insulating boards, and flooring materials), the automotive industry (interior moldings), the footwear industry (shoe soles), and anti-static moldings. These new compounds can be employed in innovative processes to reduce their carbon footprint and negative impact on our planet. Using the Lorenz–Park equation, the loaded composites examined in this study exhibited values above 0.7, which means a competitive load–rubber interaction. Scanning electron microscopy (SEM) was used to investigate the morphology of the composites in detail.

In the last decade, natural fibers have had a significant impact on the research and development of innovative composites made with natural rubber, improving their properties over those of their counterparts that incorporate polluting synthetic fibers. In recent years, this fact has stimulated the research into several modified natural rubber composites reinforced with vegetable fibers. This paper reviews the scientific literature published in the last decade about the properties and characteristics of natural vegetable fibers and natural rubber used in composites. Nowadays the use of alternative materials has become necessary, considering that synthetic materials have caused irreversible damage to the environment, being associated with global warming, for this reason research and development with materials that print a lower carbon footprint during the manufacturing process and subsequent product manufacturing. This review is an invitation to the use of vegetable fibers, as well as vegetable-type matrices, in this case natural rubber as a binder system, it is fantastic to know the different works carried out by other scientists and engineers, in this way to project new compounds linked to innovation in processes that reduce the carbon footprint and its negative impact on our planet.

This article studies natural food packaging as enabling artifacts of the traditional material culture of Antioquia in Colombia. For this purpose, we consider artifacts as objective nodes that combine design and use intentions, functions, materials, histories, artifactual lineages, and cooperative relationships that stabilize ritualized practices of a human group. We take the example of natural packaging as artifacts that enablers and stabilizers of traditional cooking and food preparation practices. Natural packaging materials are here assumed to be leaves having some favorable property to contain a food product. After providing a theoretical reflection, we analyze the data collected from fieldwork we conducted in two towns in Antioquia, Colombia (Santa Fe de Antioquia and Amagá), as well as from an interview with an expert in the field. Finally, we show that it is possible to postulate an analysis under a relational ontological description of a traditional practice with conceptual categories of the philosophy of technology.

Culture has traditionally been considered as a set of knowledge, beliefs, arts, laws, norms, and morals, acquired by a human being as a member of a group. Some anthropologists interpret this as a set of abstract representations, such as information or knowledge, while others interpret it as behavioral control mechanisms. These views assume that the contents of a particular culture must be processed by the minds of individuals, either in a direct way or by resorting to learned mental structures in processes of symbolic socialization. Some critics suggest a problem with these perspectives since they do not provide a convincing explanation of the enculturation process beyond metaphorical images of transfer or internalization of symbolic cultural contents through linguistic transmission. The new embodied theories of cognition, especially enactivism, could give new ideas about what enculturation processes are like, through the concept of participatory sense-making in material culture environments. In this essay, we discuss how an enactive vision of culture could be, and what advantages it would have, as well as the challenges and weaknesses in explaining the culture and its learning processes.

The circular economy is a process through which elements that have already been used are reincorporated and given a second use so that they can reduce the consumption of virgin raw materials. This article shows how, from the reuse of an agro-industrial waste such as corn husks, a biomaterial can be developed that manages to standardize the properties of materials such as paper and cardboard, thus allowing the development of single-use products that replace the excessive expense of materials such as polymers. In this article, it will be possible to show how from the process of transforming an agro-industrial waste into a raw material base, it is possible not only to reduce the number of raw materials discarded but also to redesign a product that not only contributes to the environmental component but also facilitates the processes of economic sustainability when generating products. As a practical case, a comparison is made between traditional fast-food packaging and how from these, a new packaging proposal can be generated, which starts from the principles of circular economy and complements sustainable design processes to make more efficient manufacturing of the mentioned product.

Cleaner production has been used for several years in Latin America to minimize waste generation while reducing material and energy consumption. Despite those environmental benefits, its implementation may sometimes lead to changes in products or processes whose environmental performance can yield either positive or negative outputs when examined within a broader context, meaning it is necessary to complement cleaner production with other environmental tools that can provide environmental assessments. This paper presents a combination of cleaner production with life cycle assessment (LCA) applied within the wood industry in a case study in Salvador, a state of Bahia (Brazil), regarding the production of two models of wooden chairs. The study selected life cycle assessment as a scientific tool to quantify the environmental impacts of the models having ILCD 2011 midpoint and cumulative energy demand methods. The results confirmed the presence of environmental tradeoffs among the models that were not considered during the cleaner production program implemented. This paper also includes a proposal of a flowchart to guide the implementation of cleaner production when deciding to implement changes in material, energy source, processes, final destination, or lifespan of the product evaluated, identifying the stages where environmental assessment like life cycle assessment may be required to address tradeoffs.

This article analyzes the behavior of surface finish and pressing time in glued pieces of eucalyptus wood. The importance of the study lies in verifying the influence of two variables (surface finish and pressing time) on the gluing of wood pieces for the furniture industry over time. For this purpose, the quality of adhesion of Eucalyptus urograndis wood pieces with polyvinyl acetate adhesive and the behavior of the wood to shear in the glue line are evaluated. It was necessary to produce test specimens according to the ABNT-NBR 7190 standard; three different surface finishes were evaluated on the faces to be adhered and three different cold pressing times, a variable that has not been analyzed in previous studies. It was possible to determine the shear resistance in the glue line and also to observe the percentage of wood failure when performing the destructive test on the test specimen 1 year after being glued. The highest shear strength was obtained for test specimens without surface finish and with a pressing time of 24 hours. With the results obtained in this study, the optimal surface finish and pressing time to be used in the furniture industry is evidenced.

Disponibilidad de las técnicas constructivas de habitación en madera, en Brasil