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Nonionic Polymers – the Vinyl Group
Published in Philip Molyneux, Water-Soluble Synthetic Polymers: Properties and Behavior, 1983
Vinylpyrrolidone may be polymerized to give PVP by free radical, anionic, and cationic mechanisms.190 Considering the most commonly used route of free radical polymerization, the undiluted monomer was originally stated to polymerize spontaneously (i.e., in the absence of added initiator) at 140°C and above;229 however, later work with more rigorously purified monomer gave no sign of spontaneous polymerization even at these high temperatures.230 With azobisisobutyronitrile (AIBN) as initiator, the polymerization rate is also sensitive to monomer purity,230 so that once again the earlier studies229 may no longer be valid; the initiator efficiency for this system has been determined more recently.231
Preparation of a carbon-based nanomaterial and its influence on construction engineering
Published in Journal of Experimental Nanoscience, 2023
The dispersant polyvinylpyrrolidone is dissolved in purified water and heated to 60 °C and kept at a constant temperature to completely dissolve. A water-soluble polymer known as polyvinylpyrrolidone (PVP) is generated when N-vinylpyrrolidone is synthesized. PVP is a polymer that helps to encapsulate and deliver both hydrophilic and lipophilic substances. It is non-toxic, inert, temperature-resistant, pH-stable, biocompatible, and biodegradable. High tensile strength, flexibility, and oxygen and aroma barrier properties are all characteristics of poly (vinyl alcohol). It also possesses superior film-forming, emulsifying, and adhesive qualities. The monomer N-vinylpyrrolidone6 is converted into the water-soluble polymer known as poly (vinylpyrrolidone). After that, we add the weighed and functionalized multi-walled carbon nanotubes, and put them in a magnetic stirrer to stir evenly. The mixture was sonicated for 60 min and cooled to room temperature. Then, we add an appropriate amount of defoamer to eliminate surface bubbles, then pour the dispersion into a cement mortar mixer and add a certain proportion of cement. Standard sand, water, and water reducing agent are mixed evenly and put into a standard cement glue triple mold (40 mm × 400mm × 160mm), then smoothed, vibrated, shaped, and covered with a wet cloth. After demolding after 24 h, it is moved to a standard curing box, and the test specimen was obtained after standard curing for 28 days (temperature 20 °C, humidity 95%).
PVP-microneedle array for drug delivery: mechanical insight, biodegradation, and recent advances
Published in Journal of Biomaterials Science, Polymer Edition, 2023
Keisham Nelson Mangang, Pragati Thakran, Jitu Halder, Kuldeep Singh Yadav, Goutam Ghosh, Deepak Pradhan, Goutam Rath, Vineet Kumar Rai
Polyvinylpyrrolidone (PVP) is a synthetic polymer synthesized by polymerizing N-vinylpyrrolidone monomer and Povidone. Being a biocompatible, non-toxic, inert, pH stable, non-ionic, and temperature-resistant polymer with a complex affinity toward water-soluble and water-insoluble drugs [15–17], it has been widely used for preparing MNs for local and systemic uses. It has good solubility in water and organic solvents. It is available in various grades (Table 1) and viscosities [16]. It presents good binding properties and stabilizes suspensions and emulsions [18]. After being introduced as a plasma volume expander in the 1940s [16], it has been widely used in pharmaceuticals [19,20], biomedical [17, 20], cosmetics [21], and food sectors [22]. PVP is used as a binder in many types of tablets [23] and has been recognized for internal use by the Food and Drug Association (FDA) [24]. Its unique features and chemistry facilitate the synthesis of various homopolymers, crosslinked-PVP, and copolymers with different molecular weights (MW) [17]. Despite these properties, little information is available about the mechanical insights and biodegradation potential of PVP alone or in combination.
Potentiating the solubility of BCS class II drug zaltoprofen using nanodispersion technology
Published in Journal of Dispersion Science and Technology, 2023
Selvakumar Muruganantham, Venkateshwaran Krishnaswami, Ruckmani Kandasamy, Shanmugarathinam Alagarsamy
To improve the solubility of BCS class II medications, polymers like Polyvinyl pyrrolidone K30 (PVP K30) and poloxamer 407 are used in pharmaceutical formulations. The combination of PVP K30 and Poloxamer 407 or separately have a significant solubilizing effect on these pharmaceuticals.[18] Water-soluble, nonionic PVP K30 is resistant to temperature changes, has a steady pH, and is biocompatible with a wide range of pharmaceuticals. Its molecular weight is around 40,000 g/mol and composed of N-vinylpyrrolidone monomer (Figure 1a). PVP K30 has a greater affinity for both hydrophilic as well as hydrophobic drugs. With its specific features, PVP K30 can combine with molecules with a low molecular weight, which enables the solubility enhancement and controlled release of the drug.[19–21] In addition, it has an excellent crystal inhibitory property which makes it easier to generate amorphous form dispersion after the drug is dispersed in it.[22]