Download or read book Improved Water Resistance and Barrier Properties of Polyvinyl Alcohol With Polyurethane Siloxane Coating for Packaging Applications written by Vijay Pandian and published by . This book was released on 2018 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Poly vinyl Alcohol written by Shweta Paralikar and published by . This book was released on 2006 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a continual interest in developing robust, flexible, durable, lightweight, waterborne polymer barrier coatings which are increasingly resistant towards both chemical warfare agents as well as an ever growing number of toxic industrial chemicals. In this study, barrier films were prepared with poly(vinyl alcohol) (PVOH) and varying amounts of cellulose nanocrystals (CNXLs) as filler. Poly(acrylic acid) (PAA) was used as a crosslinking agent to provide water resistance to PVOH. The films were heat treated at various temperatures (125, 150, 170, 185 °C) in order to determine the optimum crosslinking density. Heat treatment at 170 °C for 45 minutes resulted in films with improved water resistance without polymer degradation. Infrared spectroscopy (FTIR) indicated ester bond formation with heat treatment. Mechanical tests showed that films with 10%CNXLs/ 10%PAA/ 80%PVOH had the highest tensile strength, tensile modulus and toughness of all the films studied. Polarized optical microscopy and atomic force microscopy showed agglomeration of CNXLs at filler loadings of 15% CNXLs. A thermogravimetric analysis (DTGA) showed highly synergistic effects with 10%CNXLs/ 10%PAA/ 80%PVOH and supported the tensile test results. The purpose of these barrier films is to prevent the diffusion of chemical warfare agents while allowing moisture to pass through to allow breathability. Water vapor transmission indicated that all the films allowed moisture to pass. However, moisture diffusion was reduced by the presence of both CNXLs and PAA compared to pure PVOH. The crystalline nature of CNXLs causes the diffusing molecules to undergo a tortuous path, while the crosslinking forms a network structure which reduces diffusion. A standard time lag diffusion test utilizing permeation cups was used to study the chemical barrier properties. The film containing 10%CNXL/ 10%PAA/ 80%PVOH showed an improvement of 90% compared to 100% PVOH film. Surface modification of CNXLs was successful and well dispersed carboxylated CNXLs were obtained. Carboxylated cellulose nanocrystals (C. CNXLs) showed less agglomeration, improved interaction, slightly reduced flux and slightly increased time lags compared to CNXLs.
Download or read book Polyvinyl Alcohol Fibers written by Ichirō Sakurada and published by CRC Press. This book was released on 1985-11-20 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polyvinyl Alcohol from Germany and Japan written by and published by DIANE Publishing. This book was released on with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polyvinyl Alcohol Properties and Applications written by C. A. Finch and published by John Wiley & Sons. This book was released on 1973 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive treatment of fully and partly hydrolyzed polyvinyl alcohol.--
Download or read book Properties and Applications of Polyvinyl Alcohol written by and published by . This book was released on 1968 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Poly vinyl Alcohol written by John G. Pritchard and published by . This book was released on 1970 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polyvinyl Alcohol Materials Processing and Applications written by Vannessa Goodship and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation. For a number of years, plastic wastes have been accumulating at such a rate that there are now huge environmental concerns with their disposal. Options such as landfill and incineration have not been well received by the public, or indeed government legislation, and focus is now firmly upon the use of biodegradable alternatives for mass applications. One material that has been considered for mass application has been polyvinyl alcohol (PVOH). To date, the use of this material has been confined to comparativey low technology applications such as paper coatings and fibre sizing, which rely upon its inherently poor resistance to moisture to initiate degradation and ultimate disposal. This Rapra Review Report provides a concise introduction to polyvinyl alcohol - the material itself, the processing and applications, and also potential future directions for PVOH.
Download or read book Polyvinyl Alcohol Film with Excellent Gas barrier Properties written by T. Sawada and published by . This book was released on 1988 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polyvinyl Alcohol Surface Modification written by Matthew Rhys Thomas and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Poly(vinyl alcohol) (PVA) is a polymer used in numerous applications, principally those in which its high water solubility is a desirable asset. However there are also areas where PVA is limited by its inherent solubility (for example some specific en- vironments in the biomedical field). This work has sought to overcome such limits by manipulating the surface of PVA in order to propose various means by which the surface solvent resistance might be increased while maintaining the bulk prop- erties of the polymer. Both chemical and physical modifications have been tried and in each case progress has been made towards insolubilizing a single surface of the polymer when in film form. Grafting various species onto the surface of PVA was successfully performed. It is believed that such species bonded to the PVA via attachment to the hydroxyl groups (though this has not been proven conclusively). The data contained herein has led to the conclusion that the primary factor in reducing solubility this way is the removal of the hydroxyl groups, and not the attachment of specifically highly hydrophobic molecules. Introducing permanent cross-links into the surface region has been attempted via various routes. The data recorded shows promise however the system is far from optimised. The biggest challenge remaining is to opti:mise the depth of material cross-linked. Some steps have been made towards understanding and controlling this parameter though there is much scope for further investigation. The methods used have built on those used for bulk cross-linking and as such are new for the case of surface specific treatment. vi An interesting phenomenon in some semi-crystalline polymers reported in recent years is that of surface specific crystallization. This effect has been successfully in- duced and observed in PVA to produce what is believed to be a highly crystalline surface layer, and crystalline regions of PVA are generally accepted to be more water resistant than amorphous ones. In summary, in this work several surface-specific treatments for PVA have been tri- alled, providing options for post-film forming modification to reduce the surface water sensitivity whilst retaining the bulk properties of the polymer.
Download or read book Biobased Aerogels written by Sabu Thomas and published by Royal Society of Chemistry. This book was released on 2018-08-23 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biobased Aerogels is the first book to cover aerogel research from a green perspective, using commentary and analysis from leading researchers working in the field.
Download or read book Polyvinyl Alcohol Film with Excellent Gas barrier Properties and Its Manufacturing Method written by S. Ohashi and published by . This book was released on 1988 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polyurethanes as Specialty Chemicals written by Timothy Thomson and published by CRC Press. This book was released on 2004-08-27 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Looking beyond the traditional applications of polyurethanes (PUR), Polyurethanes as Specialty Chemicals presents a different approach to polyurethane chemistry by examining a range of new products and new research for both environmental and medical applications. This book is also the first in its field to provide useful design tools for product de
Download or read book Advances in Structural Adhesive Bonding written by David A. Dillard and published by Elsevier. This book was released on 2010-03-31 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adhesive bonding is often effective, efficient, and often necessary way to join mechanical structures. This important book reviews the most recent improvements in adhesive bonding and their wide-ranging potential in structural engineering.Part one reviews advances in the most commonly used groups of structural adhesives with chapters covering topics such as epoxy, polyurethane, silicone, cyanoacrylate, and acrylic adhesives. The second set of chapters covers the various types of adherends and pre-treatment methods for a range of structural materials such as metals, composites and plastics. Chapters in Part three analyse methods and techniques with topics on joint design, life prediction, fracture mechanics and testing. The final group of chapters gives useful and practical insights into the problems and solutions of adhesive bonding in a variety of hostile environments such as chemical, wet and extreme temperatures.With its distinguished editor and international team of contributors, Advances in structural adhesive bonding is a standard reference for structural and chemical engineers in industry and the academic sector. - Reviews advances in the most commonly used groups of structural adhesives including epoxy, silicone and acrylic adhesives - Examines key issues in adhesive selection featuring substrate compatibility and manufacturing demands - Documents advances in bonding metals, plastics and composites recognising problems and limitations
Download or read book Polymer Nanoclay Composites written by Stephan Laske and published by William Andrew. This book was released on 2015-01-09 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a major lack of fundamental knowledge and understanding on the interaction between a filler and the polymer matrix. When it comes to nanoscale fillers, such as layered silicates, carbon nanotubes, graphene or cellulose nanofibers it is even more important to know accurate structure-property relationships as well as identifying the parameters influencing material behavior. The reason for the lack of knowledge on how to process nanocomposites and why there are so few applications is that several scientific fields are affected and a joint effort of those scientific communities involved is necessary – starting from the filler manufacturing or pre-processing over polymer chemistry to the polymer processing. In Polymer Nanoclay Composites, all involved scientific areas are viewed together for the first time, providing an all-embracing coverage of all stages of polymer clay nanocomposites processing from lab-scale to industrial scale – stages from the raw material over manufacturing of polymer clay nanocomposites to characterization and the final products. Readers will gain insight in the physical/chemical pre-processing of layered silicates and their incorporation into a polymer matrix using sophisticated technologies (such as advanced compounding) as well as in real-time quality control of the nanocomposite production and future prospects. The book also describes nanotoxicological and nanosafety aspects. - Covers the whole processing route with all aspects of the nanocomposites industry with particular focus on the processing of polymer clay nanocomposites - Includes quality control and nanosafety - Multidisciplinary approach from an industrial perspective
Download or read book Self Healing Polymers written by Wolfgang H. Binder and published by John Wiley & Sons. This book was released on 2013-03-29 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-healing is a well-known phenomenon in nature: a broken bone merges after some time and if skin is damaged, the wound will stop bleeding and heals again. This concept can be mimicked in order to create polymeric materials with the ability to regenerate after they have suffered degradation or wear. Already realized applications are used in aerospace engineering, and current research in this fascinating field shows how different self-healing mechanisms proven successful by nature can be adapted to produce even more versatile materials. The book combines the knowledge of an international panel of experts in the field and provides the reader with chemical and physical concepts for self-healing polymers, including aspects of biomimetic processes of healing in nature. It shows how to design self-healing polymers and explains the dynamics in these systems. Different self-healing concepts such as encapsulated systems and supramolecular systems are detailed. Chapters on analysis and friction detection in self-healing polymers and on applications round off the book.
Download or read book Clay Polymer Nanocomposites written by Khouloud Jlassi and published by Elsevier. This book was released on 2017-07-26 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clay–Polymer Nanocomposites is a complete summary of the existing knowledge on this topic, from the basic concepts of synthesis and design to their applications in timely topics such as high-performance composites, environment, and energy issues. This book covers many aspects of synthesis such as in- situ polymerization within the interlamellar spacing of the clays or by reaction of pristine or pre-modified clays with reactive polymers and prepolymers. Indeed, nanocomposites can be prepared at industrial scale by melt mixing. Regardless the synthesis method, much is said in this book about the importance of theclay pre-modification step, which is demonstrated to be effective, on many occasions, in obtaining exfoliated nanocomposites. Clay–Polymer Nanocomposites reports the background to numerous characterization methods including solid state NMR, neutron scattering, diffraction and vibrational techniques as well as surface analytical methods, namely XPS, inverse gas chromatography and nitrogen adsorption to probe surface composition, wetting and textural/structural properties. Although not described in dedicated chapters, numerous X-ray diffraction patterns of clay–polymer nanocomposites and reference materials are displayed to account for the effects of intercalation and exfoliations of layered aluminosilicates. Finally, multiscale molecular simulation protocols are presenting for predicting morphologies and properties of nanostructured polymer systems with industrial relevance. As far as applications are concerned, Clay–Polymer Nanocomposites examines structural composites such as clay–epoxy and clay–biopolymers, the use of clay–polymer nanocomposites as reactive nanocomposite fillers, catalytic clay-(conductive) polymers and similar nanocomposites for the uptake of hazardous compounds or for controlled drug release, antibacterial applications, energy storage, and more. - The most comprehensive coverage of the state of the art in clay–polymer nanocomposites, from synthesis and design to opportunities and applications - Covers the various methods of characterization of clay–polymer nanocomposites - including spectroscopy, thermal analyses, and X-ray diffraction - Includes a discussion of a range of application areas, including biomedicine, energy storage, biofouling resistance, and more
