Synthesis and Characterization of Copolymers from Lignin

Synthesis and Characterization of Copolymers from Lignin
Author: Hui Li
Publisher:
Total Pages: 346
Release: 2014
Genre: Copolymers
ISBN:

Development of bio-based materials, especially from agricultural and forestry industrial byproduct streams, is urgent and necessary under the circumstances of sustainability and the environment. Industrial lignin is an underutilized biopolymer byproduct from both the pulping and cellulosic ethanol biorefinery industries with tremendous availability, showing potential as a substrate for producing biobased polyester materials because of its structure and abundance of hydroxyl functional groups. In this study, lignin based copolymeric elastomers were synthesized by simple one pot two step polycondensation of methanol soluble (MS) fractions of industrial lignins and a series hyperbranched prepolymers (HBP) with different branching and core structures using various multifunctional monomers. Specifically, three industrial lignins (Indulin AT Kraft softwood (IN), Protobind 1000 (PB), and corn stover (CS)) were first subjected to methanol fractionation and then to a detailed chemical and thermal characterization. Fractionation and characterization of three industrial lignins were carried out to provide a hard (or netpoint) segment substrate for the copolymer synthesis. Correlations between chemical and thermal properties were observed in terms of condensation index, hydroxyl group, and molar mass versus the glass transition temperature (Tg̳). A series of lignin-copolymers were prepared using the three different lignins and a HBP composed of triethanolamine (TEA, trifunctional) and adipic acid (AA, difunctional), A2B3) to evaluate the effects of lignin types and lignin contents. Tensile properties were dominated by HBP 45% lignin content while lignin dominated at 45% content. The copolymers Tg̳ increased with lignin content, while lignin type did not play a significant role. Thermally-stimulated dual shape memory effects (Ts̳-SME) of the copolymers were obtained and quantified by cyclic thermomechanical tests. All copolymers had shape fixity rate 95% and shape recovery >90% for all copolymers. The copolymer shape memory transition temperature (Tt̳r̳a̳n̳s̳) increased with lignin content and Tt̳r̳a̳n̳s̳ was 20°C higher than Tg̳. To obtain different HBP structure, a prepolymer was synthesized composing of long alkyl (C12) chain diacid (DDDA), TEA, and tris(hydroxymethyl)aminomethane (THAM, tetrafunctional), B3-A2-CB31). The C12 diacid contributed to a partially crystalline structure, while THAM contributed to more branching as well as forming stiff amide linkages in the prepolymer. Lignin-copolymers were synthesized with these prepolymers and PB lignin. Tensile properties were dominated by HBP 25% lignin content while lignin dominated 25% content. The Tg̳s of copolymers increased with lignin content. The lignin-copolymer with 30% lignin content demonstrated optimal mechanical properties (tensile strength 5.3 MPa, Young's modulus 8.9 MPa, strain at break 301%, and toughness 1.03 GPa). Good Ts̳-SME was obtained and could be tailored by lignin content and activation temperatures ranged between ambient and body temperature. Finally, in order to pursue higher biobased content in the lignin-copolymers, HBP were prepared from AA, Glycerol (Gly, trifunctional), and enhanced by additions of diisopropanolamine (DIPA, trifunctional), or THAM, B2B32-A2, B2B32-DB42- A2, and B2B32-CB13- A2) to form branched to hyper branched structures. The higher branching crosslinkers, DIPA and THAM, were shown to influence the chemical and thermal properties of the prepolymers. The highly biobased lignin-copolymers demonstrated good shape memory and elastic properties. Tt̳r̳a̳n̳s̳ could be tuned by variations of Gly, DIPA and THAM proportions for applications under different temperature circumstances. Different branching and core structures of prepolymers (soft segment) were shown to influence the properties prepolymers and corresponding lignin-copolymers. All the lignin-copolymers were shown to be elastomeric and possess great Ts̳-SME. The results demonstrated that properties of lignin-copolymers could be tuned through lignin type, lignin content, prepolymer structure, and monomer variations. This study demonstrated that lignin, a renewable byproduct, can be promisingly valorized to apply as a netpoint segment in biobased polymer systems with SME behavior. [Letters with double underscore are subscript.]

Synthesis and Characterization of Novel Functional Lignins -

Synthesis and Characterization of Novel Functional Lignins -
Author: Jennifer Dietz
Publisher: Apprimus Wissenschaftsverlag
Total Pages: 301
Release: 2015-12-02
Genre: Science
ISBN: 386359388X

This thesis presents novel pathways for one step or two step modifications of different types of lignin without the need of any catalyst. Such novel functional lignins were characterized in detail and are now ready for their utilization in novel polymeric materials and thus for new applications. Hereby the value of lignin can be increased by offering novel strategies of incorporating lignins as building block into polyurethanes, but also various other polymer matrices are thinkable for future studies.

Synthesis and Characterization of a Lignin Based Thermoplastic

Synthesis and Characterization of a Lignin Based Thermoplastic
Author: Eric L. Young
Publisher:
Total Pages: 0
Release: 2017
Genre: Chemistry, Technical
ISBN:

Lignin based copolymers were synthesized using a single pot, solvent free, melt condensation reaction. The synthesis occurred in two stages. In the first stage a prepolymer consisting of a diol and diacid with varying amounts diamine was heated under vacuum. In the second stage, prepolymer was mixed with kraft lignin and further reacted under vacuum at elevated temperature. Progression of polymerization was monitored using FT-IR and ESI-MS. Polymer properties were characterized using DMA, DSC and TGA techniques. The morphology was analyzed using polarized optical microscopy. Polymer mechanical properties were found to be influenced by the type of diacid, lignin and diamine content, ball milling of lignin and presence of an acid catalyst. The lignin-copolymers were shown to have thermoplastic behavior. Additionally, above 30 wt% lignin the lignin-copolymers did not exhibit melt behavior.

Lignin

Lignin
Author: Swati Sharma
Publisher: Springer Nature
Total Pages: 304
Release: 2020-04-13
Genre: Technology & Engineering
ISBN: 3030406636

This book presents a comprehensive overview on origin, structure, properties, modification strategies and applications of the biopolymer lignin. It is organized into four themed parts. The first part focuses on the analysis and characterization of the second most abundant biopolymer. The following part is devoted to the biological aspects of lignin such as biosynthesis and degradation. In the third part, chemical modification strategies and the preparation of composites as well as nano- and microparticles are discussed.The final part addresses the industrial application of lignin and its derivatives, as well as lignin materials. The usage for synthesis of biofuels, fine chemicals and in agriculture and food industry is covered. This book is a comprehensive source for researchers, scientists and engineers working in the field of biopolymers as well as renewable materials and sources.

Monomers, Polymers and Composites from Renewable Resources

Monomers, Polymers and Composites from Renewable Resources
Author: Mohamed Naceur Belgacem
Publisher: Elsevier
Total Pages: 562
Release: 2011-10-10
Genre: Technology & Engineering
ISBN: 0080560512

The progressive dwindling of fossil resources, coupled with the drastic increase in oil prices, have sparked a feverish activity in search of alternatives based on renewable resources for the production of energy. Given the predominance of petroleum- and carbon-based chemistry for the manufacture of organic chemical commodities, a similar preoccupation has recently generated numerous initiatives aimed at replacing these fossil sources with renewable counterparts. In particular, major efforts are being conducted in the field of polymer science and technology to prepare macromolecular materials based on renewable resources. The concept of the bio-refinery, viz. the rational exploitation of the vegetable biomass in terms of the separation of its components and their utilisation as such, or after suitable chemical modifications, is thus gaining momentum and considerable financial backing from both the public and private sectors. This collection of chapters, each one written by internationally recognised experts in the corresponding field, covers in a comprehensive fashion all the major aspects related to the synthesis, characterization and properties of macromolecular materials prepared using renewable resources as such, or after appropriate modifications. Thus, monomers such as terpenes and furans, oligomers like rosin and tannins, and polymers ranging from cellulose to proteins and including macromolecules synthesized by microbes, are discussed with the purpose of showing the extraordinary variety of materials that can be prepared from their intelligent exploitation. Particular emphasis has been placed on recent advances and imminent perspectives, given the incessantly growing interest that this area is experiencing in both the scientific and technological realms. Discusses bio-refining with explicit application to materials Replete with examples of applications of the concept of sustainable development Presents an impressive variety of novel macromolecular materials

Synthesis and Characterization of Sustainable and Biobased Copolymers from Lignocellulosic

Synthesis and Characterization of Sustainable and Biobased Copolymers from Lignocellulosic
Author: Guery Saenz
Publisher:
Total Pages: 0
Release: 2022
Genre:
ISBN:

Natural compounds have been the primary resource used to produce polymeric materials by humankind since the mid-1900s. Yet, progress in bio-based polymers from renewable feedstock has encountered some obstacles, mainly due to the low prices of petroleum-based monomers, compared to natural and sustainable materials. However, most commodity plastics are non-degradable materials, and solid plastic waste accumulation adversely affects the environment. As the world population is growing and demanding chemicals, energy, and plastics materials, polymer research is focusing on synthesizing bio-based and degradable polymers. Thus, biomass, a sustainable and inexpensive feedstock, is highly appropriate for designing alternative thermoplastics that are degradable to reduce the current environmental issues. In this dissertation, three different approaches were used to afford alternative thermoplastics to petroleum‐based commodities: bio-based poly(ether-amide)s, random aromatic copolyesters, and copoly(acetal triazole)s. In our first approach, two new lignin‐derived poly(ether‐amide)s (PEA)s were prepared. Their thermal properties showed high degradation temperature (Td) ranging from 330 °C to 380 °C, and glass transition temperature (Tg) between 100 °C and 120 °C. The chemical degradation studies revealed that the PEAs were degradable in 4 M H2SO4, HNO3, and TFA in 3 days. The second polymer group synthesized were semicrystalline bio-based aromatic copolyesters with tunable thermal properties. The thermal analysis of these copolyesters revealed high Td (413 °C to 446 °C) and Tg and Tm ranging from –36 °C to 67 °C and 60 °C to 267 °C, respectively. Their crystallization behavior showed a dependence on the comonomer composition, exhibiting a pseudo-eutectic region. Finally, furfural- and benzaldehyde-based copoly(acetal triazole)s (Td range 280–340 °C) were prepared by click polymerization at room temperature. Preliminary results showed that furfural-based copoly(acetal triazole)s were susceptible to hydrolytic degradation under neutral conditions after only 8 days at 40 °C. Overall, degradable and bio-based polymers were successfully synthesized as a potential thermoplastic alternative for packaging applications.

Lignin-based Materials for Biomedical Applications

Lignin-based Materials for Biomedical Applications
Author: Patrícia Figueiredo
Publisher: Elsevier
Total Pages: 450
Release: 2021-07-26
Genre: Technology & Engineering
ISBN: 0128203048

Lignin-based Materials for Biomedical Applications: Preparation, Characterization, and Implementation explores the emerging area of lignin-based materials as a platform for advanced biomedical applications, guiding the reader from source through to implementation. The first part of the book introduces the basics of lignin, including extraction methods, chemical modifications, structure and composition, and properties that make lignin suitable for biomedical applications. In addition, structural characterization techniques are described in detail. The next chapters focus on the preparation of lignin-based materials for biomedical applications, presenting methodologies for lignin-based nanoparticles, hydrogels, aerogels, and nanofibers, and providing in-depth coverage of lignin-based materials with specific properties—including antioxidant properties, UV absorbing capability, antimicrobial properties, and colloidal particles with tailored properties—and applications, such as drug and gene delivery, and tissue engineering. Finally, future perspectives and possible new applications are considered. This is an essential reference for all those with an interest in lignin-based materials and their biomedical applications, including researchers and advanced students across bio-based polymers, polymer science, polymer chemistry, biomaterials, nanotechnology, materials science and engineering, drug delivery, and biomedical engineering, as well as industrial R&D and scientists involved with bio-based polymers, specifically for biomedical applications. Unlocks the potential of lignin-based materials with advanced properties for cutting-edge applications in areas such as drug delivery, gene delivery and tissue engineering Presents state-of-the-art methodologies used in the development of lignin-based nanoparticles, hydrogels, aerogels and nanofibers Explains the fundamentals of lignin, including structure and composition, extraction and isolation methods, types and properties, chemical modifications, and characterization techniques