Molecular iodine/polymer complexes

2013 ◽  
Vol 33 (5) ◽  
pp. 389-443 ◽  
Author(s):  
Saad Moulay
Keyword(s):  
Polymeric Materials ◽  
Molecular Iodine ◽  
Synthetic Polymers ◽  
Vinyl Pyrrolidone ◽  
Poly Vinyl Alcohol ◽  
Polymer Complex ◽  
Natural Polymers ◽  
Polymer Complexes ◽  
Conductivity Enhancement ◽  
Unexpected Findings

Abstract A unique feature of molecular iodine by far, is its ability to bind to polymeric materials. A plethora of natural and synthetic polymers develop complexes when treated with molecular iodine, or with a mixture of molecular iodine and potassium iodide. Many unexpected findings have been encountered upon complexation of iodine and the polymer skeleton, including the color formation, the polymer morphology changes, the complexation sites or regions, the biological activity, and the electrical conductivity enhancement of the complexes, with polyiodides (In¯), mainly I3¯ and I5¯, as the actual binding species. Natural polymers that afford such complexes with iodine species are starch (amylose and amylopectin), chitosan, glycogen, silk, wool, albumin, cellulose, xylan, and natural rubber; iodine-starch being the oldest iodine-natural polymer complex. By contrast, numerous synthetic polymers are prone to make complexes, including poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), nylons, poly(Schiff base)s, polyaniline, unsaturated polyhydrocarbons (carbon nanotubes, fullerenes C60/C70, polyacetylene; iodine-PVA being the oldest iodine-synthetic polymer complex.

scholarly journals Interpenetrating polymeric hydrogels as favorable materials for hygienic applications

2020 ◽  
Vol 10 (2) ◽  
pp. 5011-5020
Keyword(s):  
Biomedical Applications ◽  
Three Dimensional ◽  
Synthetic Polymers ◽  
Poly Vinyl Alcohol ◽  
Ambient Conditions ◽  
Natural Polymers ◽  
Dimensional Network ◽  
Swelling Capacity ◽  
Polymeric Chains ◽  
Poly Ethylene

Polymers can crosslink to produce intermingled materials with three-dimensional network structure known as interpenetrating polymeric network (IPN). They comprise elastic crosslinked polymeric chains. The chains of the hydrogels are either physically or chemically entangled together. Interpenetrating hydrogels can be tailored to provide enhanced materials. They can be classified according to methods of their synthesis as simultaneous or sequential IPNs and the structure to be homo or semi IPNs. The preparation factors play a role in controlling the properties of the produced IPNs. Moreover, the ambient conditions such as pH, temperature as well as the ionic strength may affect the performance of these hydrogels. The swelling capacity is an important feature that allows the prepared hydrogel to perform the required application. Some disadvantages may arise such as the low mechanical properties that are suggested to be overcome. IPNs can be used in various applications that serve the human requirements like drug delivery, tissue engineering, medical and packaging applications. Hydrogels present biocompatibility and nontoxicity when used in biomedical applications. Interpenetrating hydrogels can be prepared from natural or synthetic polymers. Polysaccharides as natural polymers can be used to produce efficient interpenetrating hydrogels. Polyacrylates, poly(ethylene glycol) and poly(vinyl alcohol) are designated as promising synthetic polymers capable of forming interpenetrating hydrogels.

scholarly journals Anionic copolymers of acrylamide and polyacrylic acid as hydroaccumulating polymeric materials

2019 ◽  
Vol 55 (2) ◽  
pp. 188-195
Author(s):  
D. N. Davlyud ◽  
Yu. V. Matrunchik ◽  
E. V. Vorobieva ◽  
D. V. Cherednichenko ◽  
P. D. Vorobiev
Keyword(s):  
Polyacrylic Acid ◽  
Moisture Absorption ◽  
Chemical Interaction ◽  
Polymeric Materials ◽  
Polymer Complex ◽  
Polymer Complexes ◽  
Synthesis Conditions ◽  
Binary Polymer ◽  
Absorption Control ◽  
High Degree

A method for hydrogels production by the formation of cross-linked binary polymer complexes is proposed. Necessary conditions for synthesis were determined, providing a high degree of swelling of hydroaccumulating polymeric materials based on anionic copolymers of acrylamide and polyacrylic acid. Chemical interaction of components of polymer complex has been proved by the methods of infrared spectroscopy and potentiometric titration. The possibility of moisture absorption control of hydrogels depending on synthesis conditions and application purpose was shown.

Molecular Modelling of Small Molecule Diffusion in Biopolymer Blends Membranes for Biomedical Applications

2006 ◽  
Author(s):  
Mariana Ionita ◽  
Davide Silvestri ◽  
Alfonso Gautieri ◽  
Emiliano Votta ◽  
Gianluca Ciardelli ◽  
...  
Keyword(s):  
Small Molecules ◽  
Diffusion Coefficients ◽  
Diffusion Constant ◽  
Polymeric Materials ◽  
Md Simulations ◽  
Synthetic Polymers ◽  
Computational Method ◽  
Poly Vinyl Alcohol ◽  
Dynamics Simulations ◽  
Biological Performance

In order to improve the biological performance of synthetic polymers and to enhance the mechanical characteristics by tailoring the permeability properties of biopolymers, a new class of specifically designed materials (bioartificial polymeric materials), consisting of blends of synthetic polymers and biopolymers, has been recently introduced. In this work we present a computational method based on molecular mechanics (MM) and dynamics (MD) techniques, to investigate their permeability to small molecules. The permeability properties was assessed of poly(vinyl alcohol)-(PVA)- dextran-(Dex) and poly(acrylic acid)-(PAA)-Dex membranes with different blend composition. Amorphous bulk models of PVA–Dex and PAA–Dex mixtures with 80:20, 60:40, 40:60 (w/w) ratios were generated. Two steps have been performed iteratively, the former using a MM simulation for equilibration and the latter using MD simulations for model refinement. Virtual uniaxial traction tests were performed, adopting the Second Derivative (SD) procedure, in order to assess the mechanical behavior of the bulk models. The diffusion coefficients for H2O were determined via NVT molecular dynamics simulations. Using the data of the motion of water inside the bulk models, the diffusivity constant was calculated applying the Einstein equation. Correlation of diffusion coefficients with free volume, was found. The results of the simulations agree with theoretical considerations: as the content of dextran increases from 80:20 to 40:60 a 86 % decrease of the diffusion constant is obtained and the values (range 0.14–56.5 10−6 cm2s−1) have the order of magnitude expected, and similar on the diffusion of small molecules in amorphous polymeric membranes.

scholarly journals Fabrication of Mechanically Reinforced Gelatin/Hydroxyapatite Bio-Composite Scaffolds by Core/Shell Nozzle Printing for Bone Tissue Engineering

2020 ◽  
Vol 21 (9) ◽  
pp. 3401 ◽  
Author(s):  
Haeri Kim ◽  
Hanjun Hwangbo ◽  
YoungWon Koo ◽  
GeunHyung Kim
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Synthetic Polymers ◽  
Compressive Modulus ◽  
Calcium Deposition ◽  
Poly Vinyl Alcohol ◽  
Target Tissue ◽  
Natural Polymers ◽  
Composite Scaffolds

In tissue engineering, biocompatible scaffolds are used as 3D cell niches to provide a similar environment to that of native tissue for seeded cells to regenerate the target tissue. When engineering bone tissue, high mechanical strength and calcium phosphate composition are essential factors to consider. In this study, we fabricated biocompatible composite scaffolds composed of synthetic polymers (polycaprolactone (PCL) and poly (vinyl alcohol) (PVA)), natural polymers (gelatin and collagen) and bioceramic (hydroxyapatite; HA) for bone tissue engineering. The synthetic polymers were used to enhance the mechanical properties of the composite scaffolds while the natural protein-based polymers were used to enhance various cellular activities, such as cell adhesion and proliferation. Meanwhile, the bioceramic was introduced to promote osteogenic differentiation. Composite scaffolds were evaluated for their physical characteristics, such as mechanical, swelling and protein absorbing properties as well as biological properties (cell proliferation, alkaline phosphatase (ALP) activities and calcium deposition) with human osteoblast-like cells (MG63). Consequently, incorporation of hydroxyapatite into the gelatin/PVA (C-GPH) scaffold showed 5-fold and 1.5-fold increase in calcium deposition and ALP activities, respectively compared to gelatin/PVA scaffold (C-GP). Moreover, compressive modulus also increased 1.8-fold. Integration of PCL core into gelatin/PVA/hydroxyapatite scaffold (C-PGPH) further amplified the compressive modulus 1.5-fold. In conclusion, the scaffold that is reinforced with HA particles and integrated with PCL core of the struts showed significant potential in field of bone tissue engineering.

scholarly journals Bioprinting Via a Dual-Gel Bioink Based on Poly(Vinyl Alcohol) and Solubilized Extracellular Matrix towards Cartilage Engineering

2021 ◽  
Vol 22 (8) ◽  
pp. 3901
Author(s):  
Mohsen Setayeshmehr ◽  
Shahzad Hafeez ◽  
Clemens van Blitterswijk ◽  
Lorenzo Moroni ◽  
Carlos Mota ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Cell Viability ◽  
Vinyl Alcohol ◽  
Compression Modulus ◽  
Synthetic Polymers ◽  
Poly Vinyl Alcohol ◽  
Cross Linking ◽  
Light Curing ◽  
Shape Retention ◽  
Amine Groups

Various hydrogel systems have been developed as biomaterial inks for bioprinting, including natural and synthetic polymers. However, the available biomaterial inks, which allow printability, cell viability, and user-defined customization, remains limited. Incorporation of biological extracellular matrix materials into tunable synthetic polymers can merge the benefits of both systems towards versatile materials for biofabrication. The aim of this study was to develop novel, cell compatible dual-component biomaterial inks and bioinks based on poly(vinyl alcohol) (PVA) and solubilized decellularized cartilage matrix (SDCM) hydrogels that can be utilized for cartilage bioprinting. In a first approach, PVA was modified with amine groups (PVA-A), and mixed with SDCM. The printability of the PVA-A/SDCM formulations cross-linked by genipin was evaluated. On the second approach, the PVA was functionalized with cis-5-norbornene-endo-2,3-dicarboxylic anhydride (PVA-Nb) to allow an ultrafast light-curing thiol-ene cross-linking. Comprehensive experiments were conducted to evaluate the influence of the SDCM ratio in mechanical properties, water uptake, swelling, cell viability, and printability of the PVA-based formulations. The studies performed with the PVA-A/SDCM formulations cross-linked by genipin showed printability, but poor shape retention due to slow cross-linking kinetics. On the other hand, the PVA-Nb/SDCM showed good printability. The results showed that incorporation of SDCM into PVA-Nb reduces the compression modulus, enhance cell viability, and bioprintability and modulate the swelling ratio of the resulted hydrogels. Results indicated that PVA-Nb hydrogels containing SDCM could be considered as versatile bioinks for cartilage bioprinting.

About the compatibility of polymer components in polymer complexes based on poly(acrylamide) and poly(vinyl alcohol)

2001 ◽  
Vol 166 (1) ◽  
pp. 117-122 ◽  
Author(s):  
Ol'ga Demchenko ◽  
Nataliya Kutsevol ◽  
Tatyana Zheltonozhskaya ◽  
Vladimir Syromyatnikov
Keyword(s):  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Polymer Complexes ◽  
Poly Acrylamide

Natural Polymers in Fast Dissolving Tablets

2021 ◽  
pp. 2859-2866
Author(s):  
Ratnaparkhi M.P. ◽  
Karnawat G.R. ◽  
Andhale R.S.
Keyword(s):  
Geriatric Patients ◽  
Nutritional Supplement ◽  
Synthetic Polymers ◽  
Oral Route ◽  
Water Soluble ◽  
Natural Polymers ◽  
Disintegration Time ◽  
Water Soluble Drug ◽  
Poorly Water Soluble ◽  
Poorly Water Soluble Drug

Oral route is most preferable route of administration for various drugs, because it is convenient, economical, safest route. Fast dissolving tablets are popular nowadays, as they disintegrated in mouth within a few seconds without using water for swallow. Problems like Dysphagia in pediatric and geriatric patients have been overcome by formulating Fast dissolving tablet. Natural polymers are preferable because they are chemically inert, nontoxic, less expensive, biodegradable, and available easily than synthetic polymers. Natural polymers are obtained from the natural origin so they are devoid of any side effect. It is proved from the previous studies that Natural polymers are more-safe and effective than the synthetic polymers. Natural polymers improve the properties of tablet and they are used as binder, diluent, superdisintegrant, they also enhance the solubility of poorly water-soluble drug, decrease the disintegration time and provide nutritional supplement. The aim of the present article is to study various natural polymers used in fast dissolving tablets.

New Carbohydrate-Based Polymeric Materials

MRS Bulletin ◽  
1992 ◽  
Vol 17 (10) ◽  
pp. 54-59 ◽  
Author(s):  
Matthew R. Callstrom ◽  
Mark D. Bednarski
Keyword(s):  
Food Additives ◽  
Polymeric Materials ◽  
Water Soluble ◽  
Natural Polymers ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
Chemically Modified ◽  
Stereochemical Control ◽  
Natural Polysaccharide ◽  
Image Position

The total world production of water-soluble polymers is estimated to be greater than five million tons per year. Water-soluble polymers are most conveniently described according to their origin in three classes (see Structures 1-6):∎ Natural polymers, including starch (1) and cellulose (2);∎ chemically modified natural polymers, including, for example, hydroxyethyl starch (3) and cellulose acetate (4); and∎ synthetic polymers, the most important of which are polyacrylamide (5) and polyvinyl alcohol (6), (commonly composed of both alcohol and acetate groups as shown). The widespread use of these materials is due to both their availability and the range of useful physical properties found in the various natural and chemically modified natural polymers.Of the commercial water-soluble polymers, approximately 50–80% are based on natural polysaccharide materials. One of the primary reasons that these materials find such widespread use is the dramatic response of their properties to changes in their functionality and stereochemistry: chemical modification or the combination of polysaccharides with other polymeric materials has yielded materials whose applications range from explosives to food additives. Although efforts directed at controlling the properties of polysaccharides has resulted in a wide variety of useful materials, we felt control of the composition of carbohydrate-based polymers at the molecular level would provide materials with properties superior to those derived from natural and chemically modified polysaccharide materials.Our approach for the preparation of new carbohydrate-based materials is to use the carbohydrate as a template for the introduction of desired functionality with complete regiochemical and stereochemical control by both chemical and enzymatic methods (Scheme I).

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