scholarly journals Hydroxyethyl Cellulose Acrylamide Graft Polymer-Bentonite Nanocomposites Synthesis, Characterization and Properties

2021 ◽  
Vol 26 (4) ◽  
Author(s):  
Songze Liao ◽  
Yi Pan ◽  
Shuangchun Yang ◽  
Guangzhi Liao ◽  
Minglei Xu ◽  
...  
Keyword(s):  
Hydroxyethyl Cellulose ◽  
Graft Polymer

Synthesis and characterization of hydroxyethyl cellulose copolymer modified polyurethane bionanocomposites

2021 ◽  
Vol 179 ◽  
pp. 345-352
Author(s):  
Fatima Zia ◽  
Zill-i-Huma Nazli ◽  
Khalid Mahmood Zia ◽  
Waseem Aftab ◽  
Shazia Tabasum ◽  
...  
Keyword(s):  
Hydroxyethyl Cellulose ◽  
Synthesis And Characterization

Hydrophobic modifications of hydroxyethyl cellulose polymers: Their influence on the acute toxicity to aquatic biota

2021 ◽  
Vol 409 ◽  
pp. 124966
Author(s):  
Anabela M. Simões ◽  
C. Venâncio ◽  
Luís Alves ◽  
Filipe E. Antunes ◽  
Isabel Lopes
Keyword(s):  
Acute Toxicity ◽  
Hydroxyethyl Cellulose ◽  
Aquatic Biota

scholarly journals Recuperative Amino Acids Separation through Cellulose Derivative Membranes with Microporous Polypropylene Fiber Matrix

Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 429
Author(s):  
Aurelia Cristina Nechifor ◽  
Andreia Pîrțac ◽  
Paul Constantin Albu ◽  
Alexandra Raluca Grosu ◽  
Florina Dumitru ◽  
...  
Keyword(s):  
Amino Acids ◽  
Cellulose Acetate ◽  
Polypropylene Fiber ◽  
Point Of View ◽  
Hydroxyethyl Cellulose ◽  
Separation Performance ◽  
Thermal Gravimetric Analyzer ◽  
Microfiltration Membranes ◽  
Ft Ir ◽  
Structural Point

The separation, concentration and transport of the amino acids through membranes have been continuously developed due to the multitude of interest amino acids of interest and the sources from which they must be recovered. At the same time, the types of membranes used in the sepa-ration of the amino acids are the most diverse: liquids, ion exchangers, inorganic, polymeric or composites. This paper addresses the recuperative separation of three amino acids (alanine, phe-nylalanine, and methionine) using membranes from cellulosic derivatives in polypropylene ma-trix. The microfiltration membranes (polypropylene hollow fibers) were impregnated with solu-tions of some cellulosic derivatives: cellulose acetate, 2-hydroxyethyl-cellulose, methyl 2-hydroxyethyl-celluloseand sodium carboxymethyl-cellulose. The obtained membranes were characterized in terms of the separation performance of the amino acids considered (retention, flux, and selectivity) and from a morphological and structural point of view: scanning electron microscopy (SEM), high resolution SEM (HR-SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS) and thermal gravimetric analyzer (TGA). The re-sults obtained show that phenylalanine has the highest fluxes through all four types of mem-branes, followed by methionine and alanine. Of the four kinds of membrane, the most suitable for recuperative separation of the considered amino acids are those based on cellulose acetate and methyl 2-hydroxyethyl-cellulose.

scholarly journals Rheological and Microstructural Features of Plant Culture Media Doped with Biopolymers: Influence on the Growth and Physiological Responses of In Vitro-Grown Shoots of Thymus lotocephalus

2021 ◽  
Vol 2 (2) ◽  
pp. 538-553
Author(s):  
Natacha Coelho ◽  
Alexandra Filipe ◽  
Bruno Medronho ◽  
Solange Magalhães ◽  
Carla Vitorino ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Culture Medium ◽  
Culture Media ◽  
Average Pore Size ◽  
Physiological Responses ◽  
Gum Arabic ◽  
Shoot Elongation ◽  
Hydroxyethyl Cellulose ◽  
Plant Culture

In vitro culture is an important biotechnological tool in plant research and an appropriate culture media is a key for a successful plant development under in vitro conditions. The use of natural compounds to improve culture media has been growing and biopolymers are interesting alternatives to synthetic compounds due to their low toxicity, biodegradability, renewability, and availability. In the present study, different culture media containing one biopolymer (chitosan, gum arabic) or a biopolymer derivative [hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC)], at 100 or 1000 mg L−1, were tested regarding their influence on the growth and physiological responses of Thymus lotocephalus in vitro culture. Cellulose-based biopolymers (HEC and CMC) and gum arabic were used for the first time in plant culture media. The results showed that CMC at 100 mg L−1 significantly improved shoot elongation while chitosan, at the highest concentration, was detrimental to T. lotocephalus. Concerning only the evaluated physiological parameters, all tested biopolymers and biopolymer derivatives are safe to plants as there was no evidence of stress-induced changes on T. lotocephalus. The rheological and microstructural features of the culture media were assessed to understand how the biopolymers and biopolymer derivatives added to the culture medium could influence shoot growth. As expected, all media presented a gel-like behaviour with minor differences in the complex viscosity at the beginning of the culture period. Most media showed increased viscosity overtime. The surface area increased with the addition of biopolymers and biopolymer derivatives to the culture media and the average pore size was considerably lower for CMC at 100 mg L−1. The smaller pores of this medium might be related to a more efficient nutrients and water uptake by T. lotocephalus shoots, leading to a significant improvement in shoot elongation. In short, this study demonstrated that the different types of biopolymers and biopolymer derivatives added to culture medium can modify their microstructure and at the right concentrations, are harmless to T. lotocephalus shoots growing in vitro, and that CMC improves shoot length.

scholarly journals Rendering Banana Plant Residues into a Potentially Commercial Byproduct by Doping Cellulose Films with Phenolic Compounds

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 843
Author(s):  
Rosa E. A. Nascimento ◽  
Joana Monte ◽  
Mafalda Cadima ◽  
Vítor D. Alves ◽  
Luísa A. Neves
Keyword(s):  
Phenolic Compounds ◽  
Food Packaging ◽  
Extraction Process ◽  
Amorphous Structure ◽  
Wound Dressings ◽  
Hydroxyethyl Cellulose ◽  
Total Phenolic ◽  
Plant Residues ◽  
Banana Plant ◽  
Hemicellulose Removal

This study seeks to render residues from banana plants into a useful byproduct with possible applications in wound dressings and food packaging. Films based on cellulose extracted from banana plant pseudostem and doped with phenolic compounds extracted from banana plant leaves were developed. The phenolic compounds were extracted using batch solid-liquid and Soxhlet methods, with different drying temperatures and periods of time. The total phenolic content and antioxidant activity were quantified. The optimum values were obtained using a three-day period batch-solid extraction at 40 °C (791.74 ± 43.75 mg/L). SEM analysis indicates that the pseudostem (PS) films have a porous structure, as opposed to hydroxyethyl cellulose (HEC) films which presented a homogeneous and dense surface. Mechanical properties confirmed the poor robustness of PS films. By contrast HEC films manifested improved tensile strength at low levels of water activity. FTIR spectroscopy reinforced the need to improve the cellulose extraction process, the success of lignin and hemicellulose removal, and the presence of phenolic compounds. XRD, TGA and contact angle analysis showed similar results for both films, with an amorphous structure, thermal stability and hydrophilic behavior.

scholarly journals Improvement of Mechanical Properties of Noil Hemp Fiber Reinforced Polypropylene Composites by Resin Modification and Fiber Treatment

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Zili Yan ◽  
Jianchun Zhang ◽  
Hua Zhang ◽  
Hao Wang
Keyword(s):  
Mechanical Properties ◽  
Mechanical Analysis ◽  
Interfacial Bonding ◽  
Hydroxyethyl Cellulose ◽  
Hemp Fiber ◽  
Polypropylene Composites ◽  
Hydrophobically Modified ◽  
Fiber Treatment ◽  
Fibre Treatment ◽  
Adhesion Factor

The present study aims to improve the reinforcement of hemp fibre to polypropylene (PP) by simple resin modification and fibre treatment. Maleic anhydride grafted polypropylene (MAPP) was used as resin modifier by direct mixing with PP, and hydrophobically modified hydroxyethyl cellulose (HMHEC) was used as fibre treatment reagent by immersing fibre into its aqueous solution. The influences of fibre content, resin modification, and fibre treatment on the mechanical properties (tensile, flexural, and impact strengths) of composites were investigated. The change of interfacial bonding between fibre and resin in composites caused by MAPP and HMHEC was studied by scanning electron microscopy and dynamic mechanical analysis. Resin modification and fibre treatment were effective to enhance the mechanical properties of the composites. The improvement in interfacial bonding is quantitatively evaluated with adhesion factor.

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