Transparent cellulose-based bio-hybrid films with enhanced anti-ultraviolet, antioxidant and antibacterial performance

Carbohydrate Polymers, Journal Year: 2022, Volume and Issue: 298, P. 120118 - 120118

Published: Sept. 16, 2022

Language: Английский

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Overcoming the Tradeoff Between Processability and Mechanical Performance of Elastomeric Vitrimers

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(52)

Published: Sept. 15, 2023

Vitrimers are polymer networks with dynamic covalent bonds that allow the network to reconfigure its connectivity while maintaining a constant number of chemical at all temperatures. The melt viscosity vitrimers thus gradually decreases temperature. This behavior makes more difficult process than typical thermoplastics using conventional processing techniques, such as extrusion. Although many strategies have been reported address this issue, it remains challenging overcome key tradeoff between improving processability or mechanical performance. Herein, work presents new strategy for overcoming in context elastomeric vitrimers. approach entails cross‐linking functionalized low‐glass transition ( T g ) matrix an incompatible high‐ featuring pendant groups complementary reactivity. When compared homogeneous vitrimer, microphase‐separated materials prepared by reactive extrusion present improved tensile properties and creep resistance room temperature also exhibiting enhanced high These consequence combination phase separation soft hard phases, restriction reactions within interfacial zones, judicious selection be use

Language: Английский

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Engineering Innovations, Challenges, and Opportunities for Lignocellulosic Biorefineries: Leveraging Biobased Polymer Production

Annual Review of Chemical and Biomolecular Engineering, Journal Year: 2023, Volume and Issue: 14(1), P. 109 - 140

Published: April 11, 2023

Alternative polymer feedstocks are highly desirable to address environmental, social, and security concerns associated with petrochemical-based materials. Lignocellulosic biomass (LCB) has emerged as one critical feedstock in this regard because it is an abundant ubiquitous renewable resource. LCB can be deconstructed generate valuable fuels, chemicals, small molecules/oligomers that amenable modification polymerization. However, the diversity of complicates evaluation biorefinery concepts areas including process scale-up, production outputs, plant economics, life-cycle management. We discuss aspects current research a focus on major stages, selection, fractionation/deconstruction, characterization, along product purification, functionalization, polymerization manufacture macromolecular highlight opportunities valorize underutilized complex feedstocks, leverage advanced characterization techniques predict manage increase fraction converted into products.

Language: Английский

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Progress in Sustainable Polymers from Biological Matter

Annual Review of Materials Research, Journal Year: 2023, Volume and Issue: 53(1), P. 81 - 104

Published: March 31, 2023

The increasing consumption of nonrenewable materials urgently calls for the design and fabrication sustainable alternatives. New generations should be derived from renewable sources, processed using environmentally friendly methods, designed considering their full life cycle, especially end-of-life fate. Here, we review recent advances in developing polymers biological matter (biomatter), including progress extraction utilization bioderived monomers polymers, as well emergence produced directly unprocessed biomatter (entire cells or tissues). We also discuss applications bioplastics, biocomposites, cementitious biomaterials, with emphasis on relating performance to underlying fundamental mechanisms. Finally, provide a future outlook material development, highlighting need more accurate accessible tools assessing life-cycle impacts socioeconomic challenges this field advances.

Language: Английский

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Polymeric Dynamic Crosslinker for Upcycling of Fragile Low-Molecular-Weight Polypropylene

ACS Applied Polymer Materials, Journal Year: 2023, Volume and Issue: 5(6), P. 4056 - 4068

Published: May 22, 2023

While tremendous progress has been made in the dynamic crosslinking of polypropylene (PP) for plastic upcycling, efficacy addressing low-molecular-weight (MW) PP waste remains untapped. In this work, we demonstrate a simple and scalable method to convert brittle low-MW vitrimer materials with enhanced thermal mechanical properties, enabling their use circular upcycling. Different from most previous work employing small-molecule crosslinkers, prepare vitrimers (PPv) using polymeric containing polyethylene glycol segments, which leads altered crystalline structures network formation. Importantly, by increasing MW crosslinkers 200 1000 Da, PPv exhibit more than 50 times increase fracture energy strong ductility, can be attributed combined effects strengthened amorphous regions semi-crystalline domains phase separation between soft segments matrix. Moreover, when blending high (PPh), PPh/PPv blends show comparable elastic modulus, yield strength, stretchability that PPh, sharp contrast widely known embrittlement PP/PPh blends. These results as an important strategy upcycling value-added products.

Language: Английский

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Fabricating Strong and Stiff Bioplastics from Whole Spirulina Cells

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(40)

Published: June 20, 2023

Abstract Since the 1950s, 8.3 billion tonnes (Bt) of virgin plastics have been produced, which around 5 Bt accumulated as waste in oceans and other natural environments, posing severe threats to entire ecosystems. The need for sustainable bio‐based alternatives traditional petroleum‐derived is evident. Bioplastics produced from unprocessed biological materials thus far suffered heterogeneous non‐cohesive morphologies, lead weak mechanical properties lack processability, hindering their industrial integration. Here, a fast, simple, scalable process presented transform raw microalgae into self‐bonded, recyclable, backyard‐compostable bioplastic with attractive surpassing those biobased such thermoplastic starch. Upon hot‐pressing, abundant photosynthetic algae spirulina forms cohesive bioplastics flexural modulus strength range 3–5 GPa 25.5–57 MPa, respectively, depending on pre‐processing conditions addition nanofillers. machinability these bioplastics, along self‐extinguishing properties, make them promising candidates consumer plastics. Mechanical recycling fast biodegradation soil are demonstrated end‐of‐life options. Finally, environmental impacts discussed terms global warming potential, highlighting benefits using carbon‐negative feedstock fabricate

Language: Английский

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Perspectives on Thermochemical Recycling of End-of-Life Plastic Wastes to Alternative Fuels

Materials, Journal Year: 2023, Volume and Issue: 16(13), P. 4563 - 4563

Published: June 24, 2023

Due to its resistance natural degradation and decomposition, plastic debris perseveres in the environment for centuries. As a lucrative material packing industries consumer products, plastics have become one of major components municipal solid waste today. The recycling is becoming difficult due lack resource recovery facilities efficient technologies separate from mixed streams. This has made oceans hotspot dispersion accumulation residues beyond landfills. article reviews sources, geographical occurrence, characteristics recyclability different types waste. presents comprehensive summary promising thermochemical technologies, such as pyrolysis, liquefaction gasification, conversion single-use wastes clean fuels. operating principles, drivers barriers plastic-to-fuel via pyrolysis (non-catalytic, catalytic, microwave plasma), well are thoroughly discussed. Thermochemical co-processing with other organic biomass produce high-quality fuel energy products also elaborated upon. Through this state-of-the-art review, it suggested that, by investing research development most pragmatic issues today, i.e., management, can be sustainably addressed greater worldwide impact.

Language: Английский

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Sustainable Polymers: Our Evolving Understanding

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(14), P. 1869 - 1878

Published: June 27, 2022

ConspectusThis Account discusses the evolution of our strategy to conduct environmentally responsible research in field polymer chemistry. To contextualize work, we begin with a broad historical overview modern environmental movement, rise sustainability as concept, and how chemistry has responded these forces, which were often sharply critical field. We then trace own responses, from graduate school onward, chronicling series experiences projects that molded, challenged, reshaped think about science.Since beginning independent careers 2004, have recognized worked resolve tension between designing synthetic polymers for specific desired thermomechanical properties minimizing impact. In early years, most strongly guided by 12 Principles Green Chemistry (12PGC), had only recently been proposed. The authors' agendas rather narrow focus on two areas, specifically catalysis biobased monomers, saw linked sustainability. Over time, found areas be too their focus, ignoring important considerations such capacity monomer supply support scale-up impact at end usage lifetimes. With respect monomers catalysts, consider descriptive metrics quantify waste production toxicity compounds used during synthesis. terms end-of-life, discuss hydrophobicity tool help understand susceptibility degradation environment well some concerns design degradation, component 12PGC.Now, after nearly decades investigation, believe achieving science will require us move beyond qualitative use 12PGC portfolio metrics. note heartening increase availability tools across These include items provide limited insight but are relatively trivial integrate into existing workflows E factor or Toxicity Estimation Software Tool. also appreciate increased Life Cycle Assessment (LCA), is both dramatically more thorough difficult deploy. Finally, propose creation national LCA center, similar instrumental core facilities. Such resource would enable this multiple phases hope effectively guide sustainable future.

Language: Английский

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iPP/PE Multiblock Copolymers for Plastic Blend Recycling Synthesized by Coordinative Chain Transfer Polymerization

Macromolecules, Journal Year: 2022, Volume and Issue: 55(15), P. 6435 - 6442

Published: July 27, 2022

Recycling of blends widely used plastics is a key challenge the envisioned circular economy, and thus, protocols permitting efficient synthesis effective compatibilizers are highly desirable. We report herein that coordinative chain transfer polymerization permits one-pot multiblock architectures strictly linear polyethylene or high-density (HDPE) isotactic polypropylene (iPP). Various block copolymers having an iPP backbone HDPE side chains were synthesized to compatibilize HDPE/iPP plastic blends. The differ in their overall molecular weights have different lengths numbers. A copolymer with weight Mp = 33,700 g × mol–1 including 4.5 Mn 600 showed highest efficiency for compatibilizing 30/70 wt % 5 compatibilizer addition. This also superior commercially available compatibilizers.

Language: Английский

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Characterization and Sustainability Potential of Recycling 3D-Printed Nylon Composite Wastes

Sustainability, Journal Year: 2022, Volume and Issue: 14(17), P. 10458 - 10458

Published: Aug. 23, 2022

The revolution of 3D-printing technology has caused an additional source plastic waste, especially the new generation composite filaments that are linked with commercial fused deposition modeling process, adding pressure to find a sustainable solution tackle emerging waste problem. This study aims investigate mechanical and thermal properties blended recycled material produced by mixing two different 3D-printed reinforced wastes, carbon fiber CF/nylon, glass GF/nylon were mixed at percentages using hot extrusion procedure, tested tensile testing machine, processed five weight ratios impact blend on characteristics composites optimum most preferred properties. results revealed maximum strength was achieved 60 wt%. highest elastic modulus value recorded wt% GF/nylon. Moreover, it noted 80 GF/nylon, ductility is peak among composites.

Language: Английский

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