Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
119,653
result(s) for
"Polymer engineering."
Sort by:
Biodegradation of Low Density Polythene (LDPE) by Pseudomonas Species
Low density polythene (LDPE) is the most widely used packaging material primarily because of its excellent mechanical properties, barrier properties against water, light weight, low cost and high energy effectiveness. However, due to its ubiquitous nature, and resistance to biodegradability, the disposal strategies are crucial and need attention. Recently, microorganisms have become the focus of interest for environmental friendly disposal of plastic and polymer-based waste. This manuscript aims to investigate the extent of biodegradability of LDPE by four different strains of Pseudomonas bacteria—Pseudomonas aeruginosa PAO1 (ATCC 15729), Pseudomonas aeruginosa (ATCC 15692), Pseudomonas putida (KT2440 ATCC 47054) and Pseudomonas syringae (DC3000 ATCC 10862). Degradation of LDPE was determined by weight loss of the sample, morphological changes, mechanical and spectroscopic variations. The eluted compounds after degradation were analysed by gas chromatography coupled with mass spectroscopy. Our results show that Pseudomonas spp. can degrade LDPE films.
Journal Article
Essentials of Polymer Flooding Technique
The production and utilization of oil has transformed our world. However, dwindling reserves are forcing industry to manage resources more efficiently, while searching for alternative fuel sources that are sustainable and environmentally friendly. Polymer flooding is an enhanced oil recovery technique that improves sweep, reduces water production, and improves recovery in geological reservoirs. This book summarizes the key factors associated with polymers and polymer flooding-from the selection of the type of polymer through characterization techniques, to field design and implementation-and discusses the main issues to consider when deploying this technology to improve oil recovery from mature reservoirs. This book introduces the area of polymer flooding at a basic level for those new to petroleum production. It describes how polymers are used to improve efficiency of \"chemical\" floods (involving surfactants and alkaline solutions). The book also offers a concise view of several key polymer-flooding topics that can't be found elsewhere.
eBook
Boosting Nanofiltration Membrane Selectivity via Amine‐Polymer Additive Engineering for Efficient Lithium Extraction From Brine
Nanofiltration (NF) membranes used in direct lithium extraction (DLE) from brine offer a more efficient and environmentally friendly alternative to traditional evaporation‐based methods, and are promising for lithium enrichment owing to their ability to selectively reject multivalent cations. However, conventional polyamide (PA) NF membranes prepared using piperazine (PIP) suffer from low Li+/Mg2+ selectivity due to excessive negative surface charge and a trade‐off between membrane permeance and selectivity. In this study, a scalable and facile strategy to enhance lithium separation performance by incorporating poly(allylamine) (PAA), an amine‐rich polymer, into the aqueous PIP solution as an additive during the interfacial polymerization synthesis of PA is presented. PAA not only introduces additional positive charges into the PA network, improving Mg2+ rejection via the Donnan effect, but also alters monomer diffusion, leading to a crumpled PA morphology that contributes to water permeance. The resulting optimum membrane exhibited a high water permeance of 12.1 L m−2 h−1 bar−1, a low LiCl rejection of 12.6 %, and significantly enhanced the rejection of MgCl2 from 18.8 % to 94.7 %. Furthermore, a two‐stage NF process using the optimized membrane effectively purified lithium from simulated salt lake brine, highlighting the potential of this strategy. A diffusion‐controlled interfacial polymerization strategy incorporating poly(allylamine) (PAA) into piperazine (PIP) solution enables precise tuning of amine monomer diffusion and polyamide (PA) network formation with trimesoyl chloride (TMC). The resulting nanofiltration membranes exhibit crumpled morphology, appropriate surface charge, and enhanced Li+/Mg2+ selectivity, demonstrating an efficient approach for lithium extraction from brines.
Journal Article
Haemodialysis membranes
Haemodialysis is an extracorporeal process in which the blood is cleansed via removal of uraemic retention products by a semipermeable membrane. Traditionally, dialysis membranes have been broadly classified on the basis of their composition (cellulosic or noncellulosic) and water permeability (low flux or high flux). However, advances in materials technology and polymer chemistry have led to the development of membranes with specific characteristics and refined properties that mandate a reconsideration of traditional membrane classification systems. For adequate characterization of these newer types of membranes, additional parameters are now relevant, including new permeability indices, the hydrophilic or hydrophobic nature of membranes, adsorption capacity and electrical potential. In this Review, we provide clinicians with an updated analysis of dialysis membranes and dialysers. We discuss the basic mechanisms that underlie solute and water removal in dialysis (that is, diffusion, convection, adsorption and ultrafiltration) in the context of treatments that use highly permeable membranes. Specifically, we highlight online haemodiafiltration and new therapies (for example, expanded haemodialysis) that utilize membranes designed to produce a high degree of internal filtration. Finally, we discuss the considerations that govern the clinically acceptable balance between large-solute clearance and albumin loss for extracorporeal therapies.
Journal Article
The Chemistry of Environmental Engineering
The focus of this book is the chemistry of environmental engineering and its applications, with a special emphasis on the use of polymers in this field.It explores the creation and use of polymers with special properties such as viscoelasticity and interpenetrating networks; examples of which include the creation of polymer-modified asphalt as.
eBook
Functional polymers by post-polymerization modification
In modern polymer science a variety of polymerization methods for the direct synthesis of polymers bearing functional groups are known. However, there is still a large number of functional groups that may either completely prevent polymerization or lead to side reactions. Post-polymerization modification, also known as polymer-analogous modification, is an alternative approach to overcome these limitations. It is based on the polymerization of monomers with functional groups that are inert towards the polymerization conditions but allow a quantitative conversion in a subsequent reaction step yielding a broad range of other functional groups. Thus, diverse libraries of functional polymers with identical average degrees of polymerization but variable side chain functionality may easily be generated. Filling the gap for a book dealing with synthetic strategies and recent developments, this volume provides a comprehensive and up-to-date overview of the field of post-polymerization modification. As such, the international team of expert authors covers a wide range of topics, including new synthetic techniques utilizing different reactive groups for post-polymerization modifications with examples ranging from modification of biomimetic and biological polymers to modification of surfaces. With its guidelines this is an indispensable and interdisciplinary reference for scientists working in both academic and industrial polymer research.
eBook
Enzyme-catalyzed amine-functionalization of poly(ethylene-glycol)
This paper presents a new method for the amine-functionalization of poly(ethylene glycol) (PEG) of Mn = 2050 g/mol via Candida antarctica lipase B (CALB)-catalyzed esterification of tert-butyloxycarbonyl (tBOC)-protected β-Alanine and L-Alanine. NMR showed full conversion for protected β-Alanine, and MALDI-ToF demonstrated the purity of the product. After deprotection, the desired diamine-functionalized PEG was obtained. Protected L-Alanine did not reach full conversion by NMR, likely due to the steric hindrance of its methyl side group.
Journal Article