Development Of Sustainable Materials Research Articles

Mechanoredox Catalysis Enables a Sustainable and Versatile Reversible Addition-Fragmentation Chain Transfer Polymerization Process.

The sustainable synthesis of macromolecules with control over sequence and molar mass remains a challenge in polymer chemistry. By coupling mechanochemistry and electron-transfer processes (i.e., mechanoredox catalysis), an energy-conscious controlled radical polymerization methodology is realized. This work explores an efficient mechanoredox reversible addition-fragmentation chain transfer (RAFT) polymerization process using mechanical stimuli by implementing piezoelectric barium titanate and a diaryliodonium initiator with minimal solvent usage. This mechanoredox RAFT process demonstrates exquisite control over poly(meth)acrylate dispersity and chain length while also showcasing an alternative to the solution-state synthesis of semifluorinated polymers that typically utilize exotic solvents and/or reagents. This chemistry will find utility in the sustainable development of materials across the energy, biomedical, and engineering communities.

Mechanoredox Catalysis Enables a Sustainable and Versatile Reversible Addition‐Fragmentation Chain Transfer Polymerization Process

AbstractThe sustainable synthesis of macromolecules with control over sequence and molar mass remains a challenge in polymer chemistry. By coupling mechanochemistry and electron‐transfer processes (i.e., mechanoredox catalysis), an energy‐conscious controlled radical polymerization methodology is realized. This work explores an efficient mechanoredox reversible addition‐fragmentation chain transfer (RAFT) polymerization process using mechanical stimuli by implementing piezoelectric barium titanate and a diaryliodonium initiator with minimal solvent usage. This mechanoredox RAFT process demonstrates exquisite control over poly(meth)acrylate dispersity and chain length while also showcasing an alternative to the solution‐state synthesis of semifluorinated polymers that typically utilize exotic solvents and/or reagents. This chemistry will find utility in the sustainable development of materials across the energy, biomedical, and engineering communities.

Combined Reprocessability and Self-Healing in Fluorinated Acrylic-Based Covalent Adaptable Networks (CANs)

Combining reprocessing and self-healing in one material provides an opportunity for the development of sustainable materials with enhanced mechanical properties. We developed fluorinated acrylic-based covalent adaptable networks (CANs) capable of self-healing and reprocessing by copolymerizing (2-acetoacetoxy)ethyl methacrylate (AAEMA), 2,2,2-trifluoroethyl methacrylate (TFEMA), and n-butyl acrylate (nBA), followed by cross-linking with tris(2-aminoethyl) amine (TREN). These materials exhibit the maximum stress at break of about 16 MPa and the storage modulus of ∼2.6 GPa in the −60 to 25 °C range. Capable of complete recovery of mechanical properties, these materials are reprocessable by compression molding at 120 °C. The recovery of physical and chemical properties involves the exchange reactions between vinylogous urethane linkages and primary amines. Upon multicycle reprocessing, junction densities and stored entropic energy are also recovered and preserved. These CANs self-heal under ambient conditions. Upon damage, initially C═O groups of vinylogous urethanes respond to perturbation by conformational changes, followed by the (E) → (Z) isomerization of C═C bonds accompanied by the conformational rearrangements of the CF3 and CH2 moieties. This reversible process leads to the recovery of dipolar interactions that facilitates self-healing under ambient conditions. The concept of equipping materials with dynamic cross-linking and self-healing attributes can be extended to other systems.

Plain metallic biomaterials: opportunities and challenges.

The 'plainification of materials' has been conceptualized to promote the sustainable development of materials. This perspective, for the first time in the field of biomaterials, proposes and defines 'plain metallic biomaterials (PMBs)' with demonstrated research and application case studies of pure titanium with high strength and toughness, and biodegradable, fine-grained and high-purity magnesium. Then, after discussing the features, benefits and opportunities of PMBs, the challenges are analyzed from both technical and regulatory aspects. Regulatory perspectives on PMB-based medical devices are also provided for the benefit of future research, development and commercialization.

Printed Humidity Sensors from Renewable and Biodegradable Materials

AbstractIncreasing environmental concerns raised by the accumulation of electronic waste draws attention to the development of sustainable materials for short‐lived electronics. In this framework, printed capacitive humidity sensors and temperature resistive detectors composed exclusively of biodegradable materials: shellac, carbon‐derived particles, and egg‐albumin are reported. The sensor platform comprises interdigitated electrodes serving as a capacitive transducer for humidity sensing, and a serpentine used as a resistive temperature detector. Both the interdigitated and serpentine electrodes are manufactured by screen‐printing carbon ink on a shellac substrate. The humidity sensors are constructed by drop‐coating egg albumin on the interdigitated carbon electrodes and the temperature detector is prepared by encapsulating the serpentine design with shellac. Shellac is shown to be a biodegradable alternative to hydrophilic cellulose‐derived substrates, with the capacitive humidity sensors demonstrating a sensitivity of 0.011% RH−1. The response and recovery times on shellac are 12 and 20 times faster than on cellulose‐based substrate, and the serpentine resistive temperature detectors have a temperature coefficient of 5300 ppm K−1. At the end of their service‐life, the sensors produced are home compostable and can be environmentally friendly disposed, potentially enabling their future use for sustainable and environmentally friendly smart‐packaging, agricultural sensing, or point‐of‐care testing.

Critical Barriers to Successful Implementation of Mn-Rich Cathodes: A Study of Low SOC Impedance

The development of sustainable materials for lithium-ion batteries is of paramount significance with the ever-growing demand of energy storage for the transportation sector. Lithium- and manganese-rich oxides are of great interests because of inherently high capacities/energies and the potential economic benefits associated with earth-abundant manganese-based compositions. With several challenges hindering the commercialization of these cathodes, there have been many studies on understanding the mechanisms of voltage fade, hysteresis, and oxygen activity. However, relatively little attention has been given to understanding the impedance of these materials. In particular, the drastic rise in area specific impedance at lower states of charge, and the overall impedance rise on extended cycling due to surface issues, are critical barriers that need to be understood and addressed to accelerate deeper market penetration.This poster will present a detailed study of the impedance behavior in cobalt-free, lithium- and manganese-rich cathodes. A combined surface-treatment/electrolyte-additive has been used to probe the behavior over long-term cycling in the absence of (i.) surface issues, (ii.) the impedance rise due to electrolyte interactions, and (iii.) capacity loss. The results presented in the poster support the hypothesis that the anomalous rise in impedance at lower states of charge is directly associated with the bulk processes of voltage fade and voltage hysteresis. Furthermore, a preliminary conceptual model is presented for understanding the impedance behavior of these activated materials, which can be described as layered-type, ordered-domain network with facile Li diffusion, where interspersed, disordered, low-voltage sites within this network hinder the Li insertion.

Mechanical and thermal properties of flax/carbon/kevlar based epoxy hybrid composites

AbstractIn recent years, awareness on environmental issues has led to development of biobased materials for a variety of engineering structural applications. Nowadays, researchers and scientists are focusing their efforts on the development of sustainable materials that make use of readily available, renewable, and biodegradable natural resources. While significant progress has been made in the study of hybrid fiber reinforced composites, the fundamental problem of incorporating and selecting the optimal combination of reinforced fibers for various applications has not been adequately addressed. Hence present study addresses the use of combination of two natural fibers with different synthetic fibers to assess the performance of the hybrid fibers composites to develop for engineering applications. In present work the effect of stacking sequence on the mechanical and thermal property of the flax, kevlar, carbon and carbon‐kevlar hybrid fiber reinforced epoxy composites are studied. The four layered composite laminates with different stacking sequence were fabricated using hand layup technique to study the mechanical properties such as tensile, flexural, interlaminar shear, and impact tests, thermal behavior, water absorption, contact angle measurement and scanning electron microscopy. The hybrid carbon/flax composite (CFFC) had better strength as compared to KFFC, HFFC, and FFFF composite laminates with better tensile strength (178.48 MPa), tensile modulus (2132 MPa), flexural strength (378.86 MPa), flexural modulus (15.76 GPa) and interlaminar shear strength (13.91 MPa) and impact strength (13.86 MPa) and water absorption behavior. The stacking sequence revealed that the hybridization of the flax with the synthetic fiber enhanced the properties as compared to the pure flax composites. The influence of the synthetic fibers at outer skin layer had the effect on enhancing the properties of composites. From the obtained results we can effectively utilize the hybrid flax fibers in some various lightweight engineering applications.

Catalyst Engineering Empowers the Creation of Biomass-Derived Polyesters and Polycarbonates.

The introduction of circular principles in chemical manufacturing will drastically change the way everyday plastics are produced, thereby affecting several aspects of the respective value chains in terms of raw feedstock, recyclability, and cost. The ultimate aim is to ensure a paradigm shift toward plastic-based (consumer) materials that overall can offer a more attractive and sustainable carbon footprint, which is an important requisite from a societal, political, and eventually economical point of view. To realize this important milestone, it is vitally important to control the polymerization processes associated with the creation of novel sustainable materials. In this respect, we realized that expanding the portfolio of biomass-derived monomers may indeed create an impetus for atom circularity; however, the often sterically congested nature of biomass-derived monomers minimizes the ability of previously developed catalysts to activate and transform these precursors. Our motivation was thus spurred by an apparent lack of catalysts suitable for addressing the conversion of such biomonomers, as we realized the potential that new catalytic processes could have to advance and contribute to the development of sustainable materials produced from polycarbonates and polyesters. These two classes of polymers represent crucial ingredients of important and large-scale consumer products and are therefore ideal fits for implementing new catalytic protocols that enable a gradual transition to plastic materials with an improved carbon footprint.When we started our research expedition, the field was dominated by metal catalysts that incorporated preferred, and in some cases even privileged, ligand backbones (such as salens) able to mediate both ring-opening and ring-opening copolymerization manifolds. One major drawback of these aforementioned catalysts is their rather rigid nature, a feature that reduces their ability to act as adaptive systems, especially in cases where bulky monomers are involved. While our initial focus was on the utilization of sustainable metal salen complexes (M = Zn, Fe) for the activation of small cyclic ethers, which are privileged monomers for polyester and polycarbonate production, we were rapidly confronted with severe limitations related to their inability to activate a wider range of complex epoxides and oxetanes, which was imparted by the planar coordination geometry of the salen ligand in most of its applied metal complexes. In our quest to find a catalytically more effective metal complex with the ability to electronically and sterically tune its substrate-binding and substrate-activation potential, we identified aminotriphenolates as structurally versatile, easily accessible, and scalable ligands for various earth-abundant metal cations. Moreover, the ligand backbone allows for switchable coordination environments around the metal centers, thus offering the necessary adaptation in substrate activation events.This Account describes how Al(III)- and Fe(III)-centered aminotriphenolates have conquered a prominent position as catalyst components in the synthesis of new biobased polyester and polycarbonate architectures, thereby changing the landscape of previously difficult to convert biomonomers, and expanding the chemical space of biobased functional polymers. With the ever-increasing influence of legislation and the restrictions placed on the use of fossil-fuel-based feedstock, the polymer industry needs viable alternatives to design materials that are greener, cost-effective, and allow for the exploration and optimization of their recycling and properties.

A sustainable single-component "Silk nacre".

Synthetic composite materials constructed by hybridizing multiple components are typically unsustainable due to inadequate recyclability and incomplete degradation. In contrast, biological materials like silk and bamboo assemble pure polymeric components into sophisticated multiscale architectures, achieving both excellent performance and full degradability. Learning from these natural examples of bio-based “single-component” composites will stimulate the development of sustainable materials. Here, we report a single-component “Silk nacre,” where nacre’s typical “brick-and-mortar” structure has been replicated with silk fibroin only and by a facile procedure combining bidirectional freezing, water vapor annealing, and densification. The biomimetic design endows the Silk nacre with mechanical properties superior to those of homogeneous silk material, as well as to many frequently used polymers. In addition, the Silk nacre shows controllable plasticity and complete biodegradability, representing an alternative substitute to conventional composite materials.

Healable, Recyclable, and Multifunctional Soft Electronics Based on Biopolymer Hydrogel and Patterned Liquid Metal.

Recent years have witnessed the rapid development of sustainable materials. Along this line, developing biodegradable or recyclable soft electronics is challenging yet important due to their versatile applications in biomedical devices, soft robots, and wearables. Although some degradable bulk hydrogels are directly used as the soft electronics, the sensing performances are usually limited due to the absence of distributed conducting circuits. Here, sustainable hydrogel-based soft electronics (HSE) are reported that integrate sensing elements and patterned liquid metal (LM) in the gelatin-alginate hybrid hydrogel. The biopolymer hydrogel is transparent, robust, resilient, and recyclable. The HSE is multifunctional; it can sense strain, temperature, heart rate (electrocardiogram), and pH. The strain sensing is sufficiently sensitive to detect a human pulse. In addition, the device serves as a model system for iontophoretic drug delivery by using patterned LM as the soft conductor and electrode. Noncontact detection of nearby objects is also achieved based on electrostatic-field-induced voltage. The LM and biopolymer hydrogel are healable, recyclable, and degradable, favoring sustainable applications and reconstruction of the device with new functions. Such HSE with multiple functions and favorable attributes should open opportunities in next-generation electronic skins and hydrogel machines.

Oxygen-rich ultramicroporous activated carbon for boosting H2 production via toluene steam reforming: Effect of H2O2-modification and Ni/Co loading

The development of sustainable materials to produce a highly stable and efficient tar removal catalyst is important for biomass gasification technology. In this study, the effect of support modification using hydrogen peroxide (H2O2) and Ni and/or Co loadings on catalytic performance over palm kernel shell-based activated carbon (AC) supported catalysts for hydrogen (H2) production via steam reforming of toluene as biomass tar model compound have been investigated. The H2O2-modified AC (ACP) registers enhanced surface oxygenated functional groups and ultramicroporosity leading to highly dispersed active metals sites with uniform distribution and high acidity after NiCo impregnation. The highest activity is conferred by 10%Ni-10%Co/ACP at 93.8% and 90.2% of H2 yield and toluene conversion, respectively, with 325 h of stability. This is attributed to high turnover frequency, small crystallite size, weak metal-support interaction (WMSI) and simultaneous NiCo reducibility. The WMSI leads to carbon nanotube formation with tip-growth mechanism and suppresses catalyst deactivation. The reaction is endothermic and non-spontaneous with an ordered system at transition state. The results imply that the oxygenated functionalized ultramicroporous palm kernel shell-based ACP has a great potential as a high-performance catalyst in steam reforming of tar for H2 production.

Supramolecular modulation of the mechanical properties of amino acid-functionalized cellulose nanocrystal films

Cellulose nanocrystal (CNC) is a promising building block for the bottom-up assembly of novel lightweight renewable materials. The ability to engineer the interfacial properties of CNC is of paramount importance to develop assembled materials for various applications; yet it remains a challenge to manipulate the supramolecular interactions within the cellulosic nanomaterials in a controlled manner. In this context, we demonstrate in this article how the assembly and mechanical properties of cellulose thin films can be controlled by manipulating the interfacial interactions of TEMPO-oxidized cellulose nanocrystals (TOCNCs) grafted with two different amino acids, arginine and tryptophan. The amino acid grafting onto the cellulose scaffold was confirmed in aqueous solutions by 1H NMR spectroscopy and in solid form by FTIR and XPS techniques. The surface functionalization of TOCNCs with simple cationic and aromatic groups provides a strategy for tuning the assembly of the nanostructures based on different supramolecular cross-linking interactions, including hydrogen bonds, π–π stacking, and cation–π interactions. In particular, we show that nanocellulose chains cross-linked by the non-covalent cation–π interactions lead to the formation of a laminated superstructure with high deformation and load standing capabilities. Our work provides a versatile strategy for tuning the surface properties of nanocellulose and represents an important step toward the development of sustainable materials with tailored mechanical properties, which will enable a wider application range of this building block all the way from tissue-engineering scaffolds to flexible devices.

Geopolymer Concrete: A Material for Sustainable Development in Indian Construction Industries

Geopolymer concrete (GPC) is a new material in the construction industry, with different chemical compositions and reactions involved in a binding material. The pozzolanic materials (industrial waste like fly ash, ground granulated blast furnace slag (GGBFS), and rice husk ash), which contain high silica and alumina, work as binding materials in the mix. Geopolymer concrete is economical, low energy consumption, thermally stable, easily workable, eco-friendly, cementless, and durable. GPC reduces carbon footprints by using industrial solid waste like slag, fly ash, and rice husk ash. Around one tonne of carbon dioxide emissions produced one tonne of cement that directly polluted the environment and increased the world’s temperature by increasing greenhouse gas production. For sustainable construction, GPC reduces the use of cement and finds the alternative of cement for the material’s binding property. So, the geopolymer concrete is an alternative to Portland cement concrete and it is a potential material having large commercial value and for sustainable development in Indian construction industries. The comprehensive survey of the literature shows that geopolymer concrete is a perfect alternative to Portland cement concrete because it has better physical, mechanical, and durable properties. Geopolymer concrete is highly resistant to acid, sulphate, and salt attack. Geopolymer concrete plays a vital role in the construction industry through its use in bridge construction, high-rise buildings, highways, tunnels, dams, and hydraulic structures, because of its high performance. It can be concluded from the review that sustainable development is achieved by employing geopolymers in Indian construction industries, because it results in lower CO2 emissions, optimum utilization of natural resources, utilization of waste materials, is more cost-effective in long life infrastructure construction, and, socially, in financial benefits and employment generation.

Geopolymers and Functionalization Strategies for the Development of Sustainable Materials in Construction Industry and Cultural Heritage Applications: A Review

In the last decades, new synthetic hybrid materials, with an inorganic and organic nature, have been developed to promote their application as protective coatings and/or structural consolidants for several substrates in the construction industry and cultural heritage field. In this context, the scientific community paid attention to geopolymers and their new hybrid functional derivatives to design and develop innovative and sustainable composites with better chemical resistance, durability and mechanical characteristics. This review offers an overview of the latest progress in geopolymer-based hybrid nanofunctional materials and their use to treat and restore cultural heritage, as well as their employment in the building and architectural engineering field. In addition, it discusses the influence of some parameters, such as the chemical and physical characteristics of the substrates, the dosage of the alkaline activator, and the curing treatment, which affect their synthesis and performance.

Mechanical, fracture toughness, and fatigue behavior of spinifex littoreus fiber on echinoidea‐spike toughened epoxy composite

AbstractNovel spinifex littores fiber‐reinforced echinoidea spike particle dispersed epoxy resin hybrid composite has been prepared and characterized. The main objective of this research work was to prepare a new system of epoxy hybrid composite comprises of surface‐treated novel spinifex littores fiber (SLF) and echinoidea spike powder (ESP) for sustainable material development. The fiber was treated with alkali and silane for effective adhesion with matrix. The composites were prepared using hand layup method and post cured at 120°C. The mechanical properties were improved with increasing particle content. The wear result shows a lowest coefficient of friction and sp. wear rate of 0.43 and 0.004 mm3/Nm for SP5 composite designation. Fracture toughness of 32.1 ± 0.69 MPa √m and energy release rate of 1.257 ± 0.071 mJ/m2 was observed for composite designation SP4. A highest fatigue life count of 26,832 was observed for composite contains 1 vol% of silane‐treated ESP and 8 h alkali cum silane‐treated SPF. The fractographs reveals toughness improved matrix phase via shear cup formation. These marine based eco‐friendly reinforcement based epoxy composites could be used in various applications in the cadre of automobile, mini‐aircrafts, structural, sports, and domestic.

A super-flexible and transparent wood film/silver nanowire electrode for optical and capacitive dual-mode sensing wood-based electronic skin

A Super-flexible and transparent wood film/silver nanowire electrode for optical and capacitive dual-mode sensing wood-based electronic skin. This work opens new directions for directly incorporating natural wood into e-skin sensors and may offer potential applications in wearable electronics, artificial intelligence, soft robots and so on. • A wood-based e-skin with instrument- and naked eye-readable characteristics. • A pyramidal microstructure polydimethlysiloxane film was used as a sensing layer. • A super-flexible transparent wood film was used as the electrodes. • The e-skin can map the spatial distribution of static and dynamic pressures. • The e-skin in luminescence exhibited a maximum sensitivity value at 1.28 kPa −1 . Flexible electronic skin (e-skin) with multimode broad-range pressure sensing and high sensitivity is highly desirable for robotics, artificial intelligence and human–machine interaction applications. Most research on e-skin has focused on improving the sensitivity of sensing layers interfaced with an electronic output device, with only a limited number of studies focused on user interfaces based on a human-readable output. Moreover, naturally degradable materials are receiving increasing attention for e-skin. Herein, inspired by a bioluminescent noctiluca, a wood-based e-skin with instrument- and naked eye-readable characteristics was sandwich assembled using silver nanowires and a super-flexible transparent wood (STW) film as an electrode and a pyramidal microstructure polydimethlysiloxane film as a stimuli-responsive layer. The electrode was prepared by depositing silver nanowires on the surface of the STW film through a Meyer rod coating method. The film demonstrated outstanding performance with high transmittance (91.4%), a small curvature radius (2 mm) and excellent sheet resistance stability even after greater than 1500 bending cycles. The e-skin showed notable changes in electroluminescence from 0 to 150 kPa (where humans feel pain) and the sensitivity remains larger than 0.15 kPa −1 over the broad pressure range. The sensitivity in capacitance exhibited high sensitivity at 1.01 kPa −1 in the low-pressure regime, meanwhile, the luminescence exhibited a maximum value at 1.28 kPa −1 at medium pressure. Furthermore, the e-skin accurately mapped the spatial distribution of static and dynamic pressures through optical sensing. This work not only improves the sustainable development of materials in electrodes but also illustrates the potential of utilizing natural wood in high value-added e-skin.

Intrinsically self-healing, reprocessable and recyclable epoxy thermosets based on dynamic reversible urea bonds

Developing self-healable, recyclable and reprocessable polymer materials is one of the effective ways to relieve plastic pollution and save resources. Using dynamic reversible hindered urea bonds (HUBs) to construct self-healing materials have become a hot topic to investigate renewable materials. HUBs have a large substituent on its nitrogen atom, which can be dynamically dissociated into related amines and isocyanates without the need for catalysts. Here, integrating HUBs into the epoxy cross-linking network would obtain dynamic covalent self-healing epoxy resin based on large hindered urea bonds (HUBs-EP), which could endow the crosslinked networks with fast reconfigurability under relatively low temperature. In this work, HUBs-EP has optional recyclability (In N, N-dimethylformamide and tetrahydrofuran), good reprocessability (under simple hot-pressing procedure) and rapid self-healing property under 110 °C within 10 min all due to reversible dissociation and recombination of dynamic covalent urea bonds. The extremely simple manufacturing method of dynamically reversible polymers obtained by integrating dynamic covalent bonds into thermoset will give a major hint for the development of sustainable materials.

Synthesis and Characterization of a Novel Bamboo Shaving Geopolymer Composite

Geopolymers are inorganic aluminosilicate materials, which have been a great research interest as a material for sustainable development. However, they possess relatively low toughness properties similar to brittle solids. The limitation may be altered by fiber reinforcement to improve their strength and toughness. This research describes the synthesis of bamboo shaving (BS) reinforced geopolymer composites and the characterization of their mechanical properties. The effect of BS content (0–2 wt. %) on the physical and mechanical properties and microstructure of metakaolin based geopolymer paste were investigated. The workability, setting time, bulk density, apparent porosity, thermal conductivity, compressive strength, flexural strength, scanning electron microscopy (SEM), and X-ray diffraction (XRD) of geopolymer paste were determined. The results showed that the workability, setting time, density, and thermal conductivity decreased with the increasing of BS content. The BS content was proportional to the apparent porosity and a good linear relation was found between apparent porosity and BS content. The highest mechanical properties were achieved at an optimum BS content of 1.0 wt. %. The results of microstructural analysis revealed that BS act as inforcing phase in matrix, reducing cracks and making a dense geopolymer, which leads to favorable adhesion of the composites and produces a geopolymer composite with better mechanical properties than that of pure geopolymer. However, when the BS content exceeded 1.0 wt. %, interfacial bonding between BS and geopolymer matrix became less. XRD analysis showed that BS has little effect on the mineral composition of metakaolin-based geopolymer and no new phase is formed.

Towards Sustainable Fisheries Through Marine Ecological Carrying Capacity Index

Overexploitation and unsustainable fisheries activities will have an impact on environmental quality degradation. In the 4.0 era, technology can assist in monitoring and managing sustainable fisheries resources. Research on sustainable fisheries management activities guided by the marine ecological carrying capacity (MECC) evaluation index has been carried out. The purpose of this study was to determine changes in fishery activity to MECC as an evaluation material for sustainable development in the fisheries sector in the form of a website. This can provide convenience and effectiveness and can be used as a basis by stakeholders in monitoring and making policies in the sustainable development of the fisheries sector. MECC is composed of two components, namely carrying object (OI) and carrier resilience (RI). OI is obtained from changes in the value of changes in human activity (RI) and socio-economic development (SI). Fishery activities are a component of RI in the Nunukan Regency, Indonesia. The HI value decreased during 2015 - 2019 and affected the decline in the MECC index as a whole. This decrease was caused by the increase in fish catches, the number of fishing households, and boat activity in the waters of the Nunukan Regency. Based on the evaluation of the decline in the value of HI, it can be used as an evaluation material in developing integrated and sustainable development in the fisheries sector by mitigating bycatch by regulating fishing gear and methodologies, as well as establishing protected area management and fishing. To make this happen, it is necessary to build partnerships between public authorities, business, civil society, academia, and the financial sector within the framework of the Penta-helix model.

Study on the Manufacturing process and Characteristics of Non-slip Outsoles Using Fiber-phase Structure of Leather Waste

This study deals with developing materials using waste leather and binders for sustainable material development by replacing butyl rubber, which is currently entirely dependent on imports. Since butyl rubber has few double bonds, the production efficiency is low because of the slow speed in the vulcanization process. Since the temperature of the process must be increased, an alternative material is required. Industries and research institutes are currently studying outsole pattern application and rubber mixing to replace butyl rubber, but technology development using recycled products is currently unavailable. This study developed an outsole material according to the type of rubber binder and the fibrous length of the leather waste. The bonding characteristics, crosslinking characteristics, abrasion resistance, and slip characteristics of the developed material were studied.