scholarly journals Process Development for Flexible Films of Industrial Cellulose Pulp Using Superbase Ionic Liquids

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1767
Author(s):  
Diana C. M. Ribeiro ◽  
Rafael C. Rebelo ◽  
Francesco De Bon ◽  
Jorge F. J. Coelho ◽  
Arménio C. Serra
Keyword(s):  
Ionic Liquids ◽  
Process Development ◽  
Mechanical Tests ◽  
Proton Nuclear Magnetic Resonance ◽  
Daily Routine ◽  
Scanning Calorimetry ◽  
Transparent Films ◽  
Cellulose Pulp ◽  
Flexible Films ◽  
Vis Spectroscopy

Due to environmental concerns, more attention has been given to the development of bio-based materials for substitution of fossil-based ones. Moreover, paper use is essential in daily routine and several applications of industrial pulp can be developed. In this study, transparent films were produced by industrial cellulose pulp solubilization in tetramethylguanidine based ionic liquids followed by its regeneration. Films were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV/Vis spectroscopy, proton nuclear magnetic resonance (1H-NMR), dynamic scanning calorimetry (DSC), thermal analysis (TG), and X-ray diffraction (XRD). Mechanical tests showed that films have a good elongation property, up to 50%, depending on ionic liquid incorporation. The influence of the conjugated acid and dissolution temperature on mechanical properties were evaluated. These results revealed the potential of this methodology for the preparation of new biobased films.

scholarly journals Preparation and Characterization of New Environmentally Friendly Starch-Cellulose Materials Modified with Casein or Gelatin for Agricultural Applications

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1684 ◽  
Author(s):  
Mirosława Prochoń ◽  
Anna Marzec ◽  
Bolesław Szadkowski
Keyword(s):  
Chemical Properties ◽  
Mechanical Tests ◽  
Infrared Analysis ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Cellulose Composites ◽  
Vis Spectroscopy ◽  
Agricultural Applications ◽  
Starch Films ◽  
Cellulose Fabrics

The purpose of this work was to prepare new biodegradable starch-cellulose composites, with starch, using casein and gelatin as natural nutrients. The physico-chemical properties of the starch films and cellulose fabrics with starch coatings were studied by Fourier transformation infrared analysis, laser confocal scanning microscopy (LCSM), scanning electron microscopy (SEM), UV-Vis spectroscopy, swelling tests, mechanical tests, thermal analysis thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The susceptibility of the starch films to biodegradation was investigated, together with their resistance to thermo-oxidative aging. As a result of the formation of the starch films, both the casein and gelatin macromolecules were able to interact directly with the starch matrix and the fractions of unbranched amylose and branched amylopectin it contained. This interaction was visible as changes in the absorption bands of the polar groups, as revealed by infrared analysis. Spectral analysis of the cellulose fabrics coated with starch films suggests that hydrogen bridges formed between the micelles of long cellulose filaments and the micro and macro-fibers of the starch pectins. An applicative test revealed that when used as a covering for bean cultivation the cellulose-starch composites act as a fertilizing component, contributing to significantly improved growth of Phaseolus vulgaris in comparison to the use of unmodified cellulose.

scholarly journals Hazardous Waste Management of Buffing Dust Collagen

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1498
Author(s):  
Miroslawa Prochon ◽  
Anna Marzec ◽  
Oleksandra Dzeikala
Keyword(s):  
Hazardous Waste ◽  
Waste Product ◽  
Mechanical Tests ◽  
Styrene Butadiene Rubber ◽  
Infrared Analysis ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Vis Spectroscopy ◽  
The Individual

Buffing Dust Collagen (BDC) is a hazardous waste product of chromium tanning bovine hides. The aim of this study was to investigate whether BDC has the desirable properties required of modern fillers. The microstructural properties of BDC were characterized by elemental analysis (N, Cr2O3) of dry residue and scanning electron microscopy (SEM). The BDC was applied (5 to 30 parts by weight) to styrene butadiene rubber (SBR), obtaining SBR-BDC composites. The physicochemical properties of the SBR-BDC composites were examined by Fourier transform infrared analysis, SEM, UV–Vis spectroscopy, swelling tests, mechanical tests, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The biodegradability of the SBR-BDC composites and their thermo-oxidative aging were also investigated. The filler contributed to increase the cross-link density in the elastomer structure, as evidenced by enhanced mechanical strength. The introduction of a filler into the elastomer structure resulted in an increase in the efficiency of polymer bonding, which was manifested by more favorable rheological and mechanical parameters. It also influenced the formation of stable interfacial bonds between the individual components in the polymer matrix, which in turn reduced the release of compact chromium in the BDC filler. This was shown by the absorption bands for polar groups in the infrared analysis and by imaging of the vulcanization process.

Soluble copolyimides containing 4,4′-isopropylidenedicyclohexanol (HBPA) isomer units: Synthesis, characterization, thermal, mechanical, and optical properties

2019 ◽  
Vol 32 (4) ◽  
pp. 406-417
Author(s):  
Ziwen Hou ◽  
Sizhuo Jin ◽  
Xiaowen Wang ◽  
Shuai Wang ◽  
Junyu Zhao ◽  
...  
Keyword(s):  
Charge Transfer Complex ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
Intermolecular Force ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Polar Solvents ◽  
Transparent Films ◽  
Structure Property Relationships ◽  
Step Procedure

In this work, 4,4′-isopropylidenedicyclohexanol (HBPA)-based dinitro isomers mixture (H″BPBN and H′BPBN) was synthesized and separated, and the structures of dinitro isomers were confirmed by differential scanning calorimetry and proton nuclear magnetic resonance spectroscopy. A series of copolyimides were prepared from diamino monomers with different percentages of novel diamine H″BPDA and 4,4′-(hexafluoroisopropylidene) diphthalic anhydride via a conventional two-step procedure. All the copolyimides could afford flexible, tough, and transparent films with transmittance no less than 73% at 450 nm, which was attributed to the fact that nonplanar alicyclic diamine and the bulky and weakly polarizable trifluoromethyl hampered the formation of charge-transfer complex. Moreover, all the copolyimides were soluble not only in polar solvents such as N,N-dimethylformamide but also in low-boiling-point solvents such as dichloromethane, which was related to the fact that the existence of alicyclic diamine and bulky trifluoromethyl decreased the intermolecular force. In addition, the conformation effects of H″BPDA and H′BPDA on the aspects of thermal, mechanical, optical, and soluble performance of copolyimides were investigated and their structure–property relationships were discussed in detail.

Geraniol and cinnamaldehyde as natural antibacterial additives for poly(lactic acid) and their plasticizing effects

2019 ◽  
Vol 40 (1) ◽  
pp. 38-48
Author(s):  
Mert Akgün ◽  
İhsan Başaran ◽  
Salih C. Suner ◽  
Ayhan Oral
Keyword(s):  
Lactic Acid ◽  
Antibacterial Activities ◽  
Mechanical Tests ◽  
Sem Analysis ◽  
Diffusion Method ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Disk Diffusion Method ◽  
Vis Spectroscopy ◽  
The Matrix

Abstract The main goal of this study is to prepare antibacterial poly(lactic acid) (PLA) containing cinnamaldehyde and geraniol and to evaluate the antibacterial activity and assess the changes of physical properties of the PLA films. Cinnamaldehyde- and geraniol-incorporated (10%, 20%, 30%, and 50% v/w) PLA films were prepared via solution-casting. While preparing these films, plasticizers were not added to the matrix. Antibacterial activities of these films against Escherichia coli and Staphylococcus aureus were investigated by the disk diffusion method. Thermal degradation characteristics were analyzed via thermogravimetric analysis (TGA), glass transition, crystallization, and melting temperatures, and enthalpies of the films were determined from differential scanning calorimetry (DSC) scans. Tensile strength and elongation-at-break values of neat PLA and antibacterial-compound-containing films were evaluated and compared after the mechanical tests. Moreover, the changes in the polymer morphology were observed by SEM analysis, and opacity of the films was determined by UV-vis spectroscopy. Our results showed that both compounds provided antibacterial effect to the PLA, with cinnamaldehyde being more effective than geraniol. Moreover, plasticization effects of the compounds were confirmed by DSC analysis.

scholarly journals Influence of lignin content in cellulose pulp on paper durability

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Edyta Małachowska ◽  
Marcin Dubowik ◽  
Piotr Boruszewski ◽  
Joanna Łojewska ◽  
Piotr Przybysz
Keyword(s):  
Lignin Content ◽  
Mechanical Tests ◽  
Accelerated Ageing ◽  
Common Belief ◽  
Oxidation Reactions ◽  
Cellulose Pulp ◽  
Aluminium Sulfate ◽  
Vis Spectroscopy ◽  
Ageing Rate ◽  
Hydrolysis Of

AbstractPaper degradation on a macroscopic scale is characterised primarily by yellowing, an increase in brittleness, and other destructive changes caused by the hydrolysis of glycoside bonds and oxidation reactions. Until now, lignin has been believed to cause these changes. However, contemporary analysis has not confirmed this assumption and has attributed low paper resistance to ageing with acidification owing to the production in acid environments that involve aluminium sulfate. In view of the common belief this manuscript presents studies on the accelerated ageing of papers with different lignin contents that are produced in neutral environments. To achieve the objective, artificially aged papers under conditions of increased humidity and temperature were investigated using chromatographic (SEC) and spectroscopic (FTIR and UV–Vis spectroscopy) techniques. Mechanical tests were used to determine the decrease in tensile properties of the samples. We observed no effects of the lignin content on the ageing rate of paper produced at neutral pH. This work also reveals the extent to which spectroscopic methods are useful for studying the papers containing lignin.

scholarly journals Dry-Jet Wet Spinning of Thermally Stable Lignin-Textile Grade Polyacrylonitrile Fibers Regenerated from Chloride-Based Ionic Liquids Compounds

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3687
Author(s):  
Muhannad Al Aiti ◽  
Amit Das ◽  
Mikko Kanerva ◽  
Maija Järventausta ◽  
Petri Johansson ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Ionic Liquids ◽  
High Performance ◽  
Paper Industry ◽  
Mechanical Tests ◽  
Coagulation Bath ◽  
Scanning Calorimetry ◽  
The Impact ◽  
Kinetics Of

In this paper, we report on the use of amorphous lignin, a waste by-product of the paper industry, for the production of high performance carbon fibers (CF) as precursor with improved thermal stability and thermo-mechanical properties. The precursor was prepared by blending of lignin with polyacrylonitrile (PAN), which was previously dissolved in an ionic liquid. The fibers thus produced offered very high thermal stability as compared with the fiber consisting of pure PAN. The molecular compatibility, miscibility, and thermal stability of the system were studied by means of shear rheological measurements. The achieved mechanical properties were found to be related to the temperature-dependent relaxation time (consistence parameter) of the spinning dope and the diffusion kinetics of the ionic liquids from the fibers into the coagulation bath. Furthermore, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical tests (DMA) were utilized to understand in-depth the thermal and the stabilization kinetics of the developed fibers and the impact of lignin on the stabilization process of the fibers. Low molecular weight lignin increased the thermally induced physical shrinkage, suggesting disturbing effects on the semi-crystalline domains of the PAN matrix, and suppressed the chemically induced shrinkage of the fibers. The knowledge gained throughout the present paper allows summarizing a novel avenue to develop lignin-based CF designed with adjusted thermal stability.

scholarly journals Innovative ionic liquids as functional agent for wood-polymer composites

Cellulose ◽  
2021 ◽  
Vol 28 (16) ◽  
pp. 10589-10608
Author(s):  
Majka Odalanowska ◽  
Andrzej Skrzypczak ◽  
Sławomir Borysiak
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Chemical Modification ◽  
Polymer Composites ◽  
Supermolecular Structure ◽  
Mechanical Tests ◽  
Hydroxyl Groups ◽  
Scanning Calorimetry ◽  
Wood Polymer ◽  
Wood Polymer Composites

AbstractChemical modification of lignocellulosic fillers is a hydrophobization process that has been used for years in the production of wood-polymer composites (WPCs). However, finding new, more effective modifiers is still a big challenge and remains the subject of much research. This study involved the chemical modification of wood with the use of newly designed ammonium and imidazolium ionic liquids containing reactive functional groups. The effectiveness of the modification was confirmed using FTIR and XRD techniques. The effect of modification of wood on the supermolecular structure and morphology of wood-polymer composites was investigated by X-ray diffraction, hot stage optical microscopy and differential scanning calorimetry. A significant influence of the modifier structure on the shaping of polymorphic varieties of the polymer matrix was demonstrated. The chemical modification also had significant effect on the nucleating properties of the wood fillers, which was confirmed by the determined crystallization parameters (crystallization half-time, crystallization temperature, crystal conversion). Moreover, the formation of a transcrystalline PP layer was noticed, which showed a large variation depending on the structure of the used ionic liquid. The obtained results correlated very well with the results of mechanical tests. It has been shown that it is possible to precisely design an ionic liquid containing a reactive functional group capable of interacting with hydroxyl groups of cellulose molecules. Moreover, the possibility of functionalizing the lignocellulosic material with innovative ionic liquids without the need to use organic solvents has not been demonstrated so far. Graphic abstract

scholarly journals Helmet Phthalocyaninato Iron Complex as a Primary Drier for Alkyd Paints

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1220
Author(s):  
Jan Honzíček ◽  
Eliška Matušková ◽  
Štěpán Voneš ◽  
Jaromír Vinklárek
Keyword(s):  
Catalytic Performance ◽  
Mechanical Tests ◽  
Iron Complex ◽  
Kinetic Measurements ◽  
Time Resolved ◽  
Strong Activity ◽  
Vis Spectroscopy ◽  
Order Of Magnitude ◽  
Transparent Coatings ◽  
Time Resolved Infrared Spectroscopy

This study describes the catalytic performance of an iron(III) complex bearing a phthalocyaninato-like ligand in two solvent-borne and two high-solid alkyd binders. Standardized mechanical tests revealed strong activity, which appeared in particular cases at concentrations about one order of magnitude lower than in the case of cobalt(II) 2-ethylhexanoate, widespread used in paint-producing industry. The effect of the iron(III) compound on autoxidation process, responsible for alkyd curing, was quantified by kinetic measurements by time-resolved infrared spectroscopy and compared with several primary driers. Effect of the drier concentration on coloration of transparent coatings was determined by UV–Vis spectroscopy.

Synthesis and properties of a benzoxazine monomer containing maleimide and biphenyl groups

2021 ◽  
pp. 095400832199674
Author(s):  
Tao Guo ◽  
Yang Fan ◽  
Chang Bo ◽  
Zhang Qi ◽  
Han Tao ◽  
...  
Keyword(s):  
Weight Loss ◽  
Loss Rate ◽  
Proton Nuclear Magnetic Resonance ◽  
Significant Weight Loss ◽  
Scanning Calorimetry ◽  
Weight Loss Rate ◽  
Reaction Heat ◽  
H Nmr ◽  
Curing Reaction ◽  
Dsc Curves

Benzoxazine resin exhibits excellent properties and is widely used in many fields. Herein, the synthesis of a novel compound, the bis(2,4-dihydro-2 H-3-(4- N-maleimido)phenyl-1,3-benzoxazinyl)biphenyl (BMIPBB), has been reported, which was synthesized by reacting N-(4-aminophenyl)maleimide (APMI), formaldehyde, and 4,4’-dihydroxybiphenyl. 1,3,5-three(4-(maleimido)phenyl)-1,3,5-triazine (TMIPT) was formed as an intermediate during the reaction. The proton nuclear magnetic resonance (1H-NMR) and Fourier transform-infrared (FTIR) spectroscopy experiments were conducted to determine the structure of BMIPBB. BMIPBB was obtained as a reddish-brown solid in 40.1% yield. The thermal properties of BMIPBB were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Analysis of the DSC curves revealed that the broad peak representing the release of curing reaction heat appeared in the temperature range of 140–330°C. The peak temperature was 242.59°C and the heat of the reaction was 393.82 J/g, indicating that the rate of the curing reaction was low and the heat of the reaction was high. Analysis of the TGA results revealed that the weight loss rate was 5% at 110°C. The monomer exhibited a significant weight loss in the range of 320–500°C. The compound lost 50% of its weight at a temperature of 427°C.

scholarly journals β-Cyclodextrin/Triclosan Complex-Grafted Methacrylated Glycol Chitosan Hydorgel by Photocrosslinking via Visible Light Irradiation for a Tissue Bio-Adhesive

2021 ◽  
Vol 22 (2) ◽  
pp. 700
Author(s):  
Young Jae Moon ◽  
Sun-Jung Yoon ◽  
Jeung-Hyun Koo ◽  
Yihyun Yoon ◽  
Hye Jun Byun ◽  
...  
Keyword(s):  
Wound Healing ◽  
Bacterial Infection ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Tissue Adhesive ◽  
Proton Nuclear Magnetic Resonance ◽  
Scanning Calorimetry ◽  
Glycol Chitosan

Accelerating wound healing with minimized bacterial infection has become a topic of interest in the development of the new generation of tissue bio-adhesives. In this study, we fabricated a hydrogel system (MGC-g-CD-ic-TCS) consisting of triclosan (TCS)-complexed beta-cyclodextrin (β-CD)-conjugated methacrylated glycol chitosan (MGC) as an antibacterial tissue adhesive. Proton nuclear magnetic resonance (1H NMR) and differential scanning calorimetry (DSC) results showed the inclusion complex formation between MGC-g-CD and TCS. The increase of storage modulus (G’) of MGC-g-CD-ic-TCS after visible light irradiation for 200 s indicated its hydrogelation. The swollen hydrogel in aqueous solution resulted in two release behaviors of an initial burst and sustained release. Importantly, in vitro and in vivo results indicated that MGC-g-CD-ic-TCS inhibited bacterial infection and improved wound healing, suggesting its high potential application as an antibacterial tissue bio-adhesive.

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