scholarly journals Fabricating Sustainable All-Cellulose Composites

2021 ◽  
Vol 11 (21) ◽  
pp. 10069
Author(s):  
Eija-Katriina Uusi-Tarkka ◽  
Mikael Skrifvars ◽  
Antti Haapala
Keyword(s):  
Driving Forces ◽  
Barrier Properties ◽  
Research Field ◽  
Raw Material ◽  
Renewable Materials ◽  
Gas Barrier ◽  
Renewable Biomass ◽  
Cellulose Composites ◽  
Cellulosic Textiles ◽  
Cellulose Nanocomposites

Climate change, waste disposal challenges, and emissions generated by the manufacture of non-renewable materials are driving forces behind the production of more sustainable composite materials. All-cellulose composites (ACCs) originate from renewable biomass, such as trees and other plants, and are considered fully biodegradable. Dissolving cellulose is a common part of manufacturing ACCs, and currently there is a lot of research focused on effective, but also more environmentally friendly cellulose solvents. There are several beneficial properties of ACC materials that make them competitive: light weight, recyclability, low toxicity, good optical, mechanical, and gas barrier properties, and abundance of renewable plant-based raw material. The most prominent ACC applications are currently found in the food packing, medical, technical and vehicle industries. All-cellulose nanocomposites (ACNCs) expand the current research field and can offer a variety of more specific and functional applications. This review provides an overview of the manufacture of sustainable ACCs from lignocellulose, purified cellulose, and cellulosic textiles. There is an introduction of the cellulose dissolution practices of creating ACCs that are currently researched, the structure of cellulose during complete or partial dissolution is discussed, and a brief overview of factors which influence composite properties is presented.

Improvement of the Functionalities of Natural Rubber/Cellulose Composites Using Epoxidized Natural Rubber

2015 ◽  
Vol 1110 ◽  
pp. 51-55
Author(s):  
Kunihiro Araki ◽  
Syonosuke Kaneko ◽  
Koki Matsumoto ◽  
Asahiro Nagatani ◽  
Tatsuya Tanaka ◽  
...  
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Barrier Properties ◽  
Vibration Damping ◽  
Butyl Rubber ◽  
Epoxidized Natural Rubber ◽  
Green Composite ◽  
Gas Barrier ◽  
Barrier Materials ◽  
Cellulose Composites

We investigated the efficient use of cellulose to resolve the problem of the depletion of fossil resources. In this study, as the biomass material, the green composite based on natural rubber (NR) and the flake-shaped cellulose particles (FSCP) was produced. Moreover, in order to improve vibration-damping and O2barrier properties, NR and epoxidized natural rubber (ENR) blends were also used. In addition, butyl rubber (IIR) was used as a target of damping or gas-barrier materials. Vibration-damping and O2barrier properties of the composite including FSCP was increased with increasing ENR content. In particular, we found that ENR-50 composite containing 50 phr FSCP has higher vibration-damping property than IIR composite containing 50 phr carbon black.

scholarly journals Impact of Backbone Amide Substitution at the Meta- and Para-Positions on the Gas Barrier Properties of Polyimide

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2097
Author(s):  
Qian Wen ◽  
Ao Tang ◽  
Chengliang Chen ◽  
Yiwu Liu ◽  
Chunguang Xiao ◽  
...  
Keyword(s):  
Transmission Rate ◽  
Barrier Properties ◽  
Polyimide Film ◽  
Flexible Display ◽  
Gas Barrier ◽  
Positron Annihilation Lifetime ◽  
Barrier Materials ◽  
Oxygen Transmission Rate ◽  
Display Technology ◽  
Gas Barrier Properties

This study designed and synthesised a meta-amide-substituted dianiline monomer (m-DABA) as a stereoisomer of DABA, a previously investigated para-amide-substituted dianiline monomer. This new monomer was polymerised with pyromellitic dianhydride (PMDA) to prepare a polyimide film (m-DABPI) in a process similar to that employed in a previous study. The relationship between the substitution positions on the monomer and the gas barrier properties of the polyimide film was investigated via molecular simulation, wide-angle X-ray diffraction (WXRD), and positron annihilation lifetime spectroscopy (PALS) to gain deeper insights into the gas barrier mechanism. The results showed that compared with the para-substituted DABPI, the m-DABPI exhibited better gas barrier properties, with a water vapour transmission rate (WVTR) and an oxygen transmission rate (OTR) as low as 2.8 g·m−2·d−1 and 3.3 cm3·m−2·d−1, respectively. This was because the meta-linked polyimide molecular chains were more tightly packed, leading to a smaller free volume and lower molecular chain mobility. These properties are not conducive to the permeation of small molecules into the film; thus, the gas barrier properties were improved. The findings have significant implications for the structural design of high-barrier materials and could promote the development of flexible display technology.

scholarly journals Clinoptilolite as a natural, active zeolite catalyst for the chemical transformations of geraniol

2021 ◽  
Author(s):  
Anna Fajdek-Bieda ◽  
Agnieszka Wróblewska ◽  
Piotr Miądlicki ◽  
Jadwiga Tołpa ◽  
Beata Michalkiewicz
Keyword(s):  
Reaction Time ◽  
Nitrogen Adsorption ◽  
Carbon Chain ◽  
Raw Material ◽  
Chemical Transformations ◽  
Renewable Biomass ◽  
Ft Ir ◽  
Catalyst Content ◽  
Favorable Conditions ◽  
Instrumental Methods

AbstractThis work presented the studies with the natural zeolite—clinoptilolite as the catalyst for the isomerization of geraniol. During the research, it turned out that the studied process is much more complicated, and not only isomerization takes place in it, but also dehydration, oxidation, dimerization, cyclization and fragmentation of the carbon chain. Geraniol is an organic raw material which can be obtained not only by a chemical synthesis but also from plants (renewable biomass) by distillation or extraction method, for example a source of geraniol can be a plant—geranium. Before catalytic tests clinoptilolite was characterized by the instrumental methods, such as: XRD, porosity studies—nitrogen adsorption at 77 K, SEM, EDXRF, and FT-IR. Gas chromatography analyses showed that the main products of geraniol isomerization process were 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol. The selectivity of 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol depended on the temperature, catalyst content and reaction time. These parameters were changed in the following ranges: 80–150 °C (temperature), 5–15 wt% (catalyst content) and 15–1440 min. (reaction time). The most favorable conditions for 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol obtaining were: temperature 140 ºC, catalyst content 12.5 wt% and reaction time 180 min. At these conditions, the conversion of geraniol amounted to 98 mol%, and the selectivities of 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol amounted to 14 and 47 mol%, respectively.

scholarly journals Renewable Biomass Utilization: A Way Forward to Establish Sustainable Chemical and Processing Industries

2021 ◽  
Vol 3 (1) ◽  
pp. 243-259
Author(s):  
Yadhu N. Guragain ◽  
Praveen V. Vadlani
Keyword(s):  
Fossil Fuels ◽  
Process Intensification ◽  
Raw Material ◽  
Biomass Composition ◽  
Biomass Feedstocks ◽  
Renewable Biomass ◽  
Sustainability Criteria ◽  
Biomass Component ◽  
Biomass Resources ◽  
Multiple Challenges

Lignocellulosic biomass feedstocks are promising alternatives to fossil fuels for meeting raw material needs of processing industries and helping transit from a linear to a circular economy and thereby meet the global sustainability criteria. The sugar platform route in the biochemical conversion process is one of the promising and extensively studied methods, which consists of four major conversion steps: pretreatment, hydrolysis, fermentation, and product purification. Each of these conversion steps has multiple challenges. Among them, the challenges associated with the pretreatment are the most significant for the overall process because this is the most expensive step in the sugar platform route and it significantly affects the efficiency of all subsequent steps on the sustainable valorization of each biomass component. However, the development of a universal pretreatment method to cater to all types of feedstock is nearly impossible due to the substantial variations in compositions and structures of biopolymers among these feedstocks. In this review, we have discussed some promising pretreatment methods, their processing and chemicals requirements, and the effect of biomass composition on deconstruction efficiencies. In addition, the global biomass resources availability and process intensification ideas for the lignocellulosic-based chemical industry have been discussed from a circularity and sustainability standpoint.

scholarly journals Diamine vapor treatment of viscoelastic graphene oxide liquid crystal for gas barrier coating

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Seung Eun Choi ◽  
Sung-Soo Kim ◽  
Eunji Choi ◽  
Ji Hoon Kim ◽  
Yunkyu Choi ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Liquid Crystal ◽  
Diffusion Length ◽  
Barrier Properties ◽  
Gas Barrier ◽  
Barrier Coating ◽  
Coating Method ◽  
Gas Molecules ◽  
Pet Film ◽  
Vapor Treatment

AbstractA layered graphene oxide/ethylenediamine (GO/EDA) composite film was developed by exposing aqueous GO liquid crystal (GOLC) coating to EDA vapor and its effects on the gas barrier performance of GO film were systematically investigated. When a GO/EDA coating with a thickness of approximately 1 μm was applied to a neat polyethylene terephthalate (PET) film, the resultant film was highly impermeable to gas molecules, particularly reducing the gas permeance up to 99.6% for He and 98.5% for H2 in comparison to the neat PET film. The gas barrier properties can be attributed to the long diffusion length through stacked GO nanosheets. The EDA can crosslink oxygen-containing groups of GO, enhancing the mechanical properties of the GO/EDA coating with hardness and elastic modulus values up to 1.14 and 28.7 GPa, respectively. By the synergistic effect of the viscoelastic properties of GOLC and the volatility of EDA, this coating method can be applied to complex geometries and EDA intercalation can be spontaneously achieved through the scaffold of the GOLC.

Biocatalysis and biomass conversion: enabling a circular economy

2020 ◽  
Vol 378 (2176) ◽  
pp. 20190274 ◽  
Author(s):  
Roger A. Sheldon
Keyword(s):  
Circular Economy ◽  
Biomass Conversion ◽  
Raw Material ◽  
Liquid Fuels ◽  
Waste Biomass ◽  
Renewable Biomass ◽  
Precious Metal Catalysts ◽  
Mitigate Climate Change ◽  
Forestry Residues ◽  
The Right

This paper is based on a lecture presented to the Royal Society in London on 24 June 2019. Two of the grand societal and technological challenges of the twenty-first century are the ‘greening' of chemicals manufacture and the ongoing transition to a sustainable, carbon neutral economy based on renewable biomass as the raw material, a so-called bio-based economy. These challenges are motivated by the need to eliminate environmental degradation and mitigate climate change. In a bio-based economy, ideally waste biomass, particularly agricultural and forestry residues and food supply chain waste, are converted to liquid fuels, commodity chemicals and biopolymers using clean, catalytic processes. Biocatalysis has the right credentials to achieve this goal. Enzymes are biocompatible, biodegradable and essentially non-hazardous. Additionally, they are derived from inexpensive renewable resources which are readily available and not subject to the large price fluctuations which undermine the long-term commercial viability of scarce precious metal catalysts. Thanks to spectacular advances in molecular biology the landscape of biocatalysis has dramatically changed in the last two decades. Developments in (meta)genomics in combination with ‘big data’ analysis have revolutionized new enzyme discovery and developments in protein engineering by directed evolution have enabled dramatic improvements in their performance. These developments have their confluence in the bio-based circular economy. This article is part of a discussion meeting issue ‘Science to enable the circular economy'.

scholarly journals Assessment and Governance of Sustainable Soil Management

2018 ◽  
Vol 10 (12) ◽  
pp. 4432 ◽  
Author(s):  
Katharina Helming ◽  
Katrin Daedlow ◽  
Bernd Hansjürgens ◽  
Thomas Koellner
Keyword(s):  
Driving Forces ◽  
Interdisciplinary Approach ◽  
Soil Management ◽  
Research Field ◽  
Future Research ◽  
Soil Functions ◽  
Special Issue ◽  
Arable Soils ◽  
Sustainable Soil Management ◽  
Production Conditions

The globally increasing demand for food, fiber, and bio-based products interferes with the ability of arable soils to perform their multiple functions and support sustainable development. Sustainable soil management under high production conditions means that soil functions contribute to ecosystem services and biodiversity, natural and economic resources are utilized efficiently, farming remains profitable, and production conditions adhere to ethical and health standards. Research in support of sustainable soil management requires an interdisciplinary approach to three interconnected challenges: (i) understanding the impacts of soil management on soil processes and soil functions; (ii) assessing the sustainability impacts of soil management, taking into account the heterogeneity of geophysical and socioeconomic conditions; and (iii) having a systemic understanding of the driving forces and constraints of farmers’ decision-making on soil management and how governance instruments may, interacting with other driving forces, steer sustainable soil management. The intention of this special issue is to take stock of an emerging interdisciplinary research field addressing the three challenges of sustainable soil management in various geographic settings. In this editorial, we summarize the contributions to the special issue and place them in the context of the state of the art. We conclude with an outline of future research needs.

Tailoring morphology to improve the gas-barrier properties of thermoplastic polyurethane/ethylene-vinyl alcohol blends

2016 ◽  
Vol 56 (8) ◽  
pp. 922-931 ◽  
Author(s):  
Xiumei Gao ◽  
Dekun Sheng ◽  
Xiangdong Liu ◽  
Tongbing Li ◽  
Fance Ji ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Thermoplastic Polyurethane ◽  
Barrier Properties ◽  
Gas Barrier ◽  
Ethylene Vinyl Alcohol ◽  
Gas Barrier Properties

Natural nanoclays: applications and future trends – a Chilean perspective

Clay Minerals ◽  
2009 ◽  
Vol 44 (2) ◽  
pp. 161-176 ◽  
Author(s):  
M. Calabi Floody ◽  
B. K. G. Theng ◽  
P. Reyes ◽  
M. L. Mora
Keyword(s):  
Agricultural Land ◽  
Clay Fraction ◽  
Barrier Properties ◽  
Clay Nanocomposites ◽  
Volcanic Soils ◽  
Gas Barrier ◽  
Important Species ◽  
The Past ◽  
Organically Modified ◽  
Water And Wastewater

AbstractBecause of their large potential for agricultural, industrial and medicinal applications, nanomaterials have been the focus of much research during the past few decades. Nanoclays are natural nanomaterials that occur in the clay fraction of soil, among which montmorillonite and allophane are the most important species. Montmorillonite is a crystalline hydrous phyllosilicate (layer silicate). Organically-modified montmorillonites or ‘organoclays’, formed by intercalation of quaternary ammonium cations, have long been used as rheological modifiers and additives in paints, inks, greases and cosmetics and as carriers and delivery systems for the controlled release of drugs. Perhaps the largest single usage of organoclays over recent years has been in the manufacture of polymer-clay nanocomposites. These organic–inorganic hybrid materials show superior mechanical, thermal and gas-barrier properties. Organoclays are also useful in pollution control and water treatment. Allophane is a non-crystalline aluminosilicate derived from the weathering of volcanic ash. A large proportion of the agricultural land in Chile is covered by volcanic soils,the clay fraction of which is dominated by allophane. Consisting of nanosize (3.5–5.0 nm) hollow spherules, allophane is a suitable support material for enzyme immobilization. Allophane is also effective at adsorbing phenolic compounds and colour from kraft mill effluents and phosphate from water and wastewater.

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