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Polyvinyl chloride is the world's third-most widely produced synthetic polymer of plastic. About 40 million tons of PVC are produced each year.
Polyvinyl acetate (PVA, PVAc, poly(ethenyl ethanoate)), commonly known as wood glue, white glue, carpenter's glue, school glue, or Elmer's glue in the US, is a widely available adhesive used for porous materials like wood, paper, and cloth. An aliphatic rubbery synthetic polymer with the formula (C4H6O2)n, it belongs to the polyvinyl ester family, with the general formula −[RCOOCHCH2]−. It is a type of thermoplastic.
Phthalates, or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften polyvinyl chloride (PVC).
Phthalic anhydride is the organic compound with the formula C6H4(CO)2O. It is the anhydride of phthalic acid. Phthalic anhydride is a principal commercial form of phthalic acid. It was the first anhydride of a dicarboxylic acid to be used commercially. This white solid is an important industrial chemical, especially for the large-scale production of plasticizers for plastics. In 2000, the worldwide production volume was estimated to be about 3 million tonnes per year.
A plasticizer is a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, or to decrease friction during its handling in manufacture.
Polymer clay is a type of hardenable modeling clay based on the polymer polyvinyl chloride (PVC). It typically contains no clay minerals, but like mineral clay a liquid is added to dry particles until it achieves gel-like working properties, and similarly, the part is put into an oven to harden, hence its colloquial designation as clay. Polymer clay is generally used for making arts and craft items, and is also used in commercial applications to make decorative parts. Art made from polymer clay can now be found in major museums.
An excipient is a substance formulated alongside the active ingredient of a medication, included for the purpose of long-term stabilization, bulking up solid formulations that contain potent active ingredients in small amounts, or to confer a therapeutic enhancement on the active ingredient in the final dosage form, such as facilitating drug absorption, reducing viscosity, or enhancing solubility. Excipients can also be useful in the manufacturing process, to aid in the handling of the active substance concerns such as by facilitating powder flowability or non-stick properties, in addition to aiding in vitro stability such as prevention of denaturation or aggregation over the expected shelf life. The selection of appropriate excipients also depends upon the route of administration and the dosage form, as well as the active ingredient and other factors. A comprehensive classification system based on structure-property-application relationships has been proposed for excipients used in parenteral medications.
Nail polish is a lacquer that can be applied to the human fingernail or toenails to decorate and protect the nail plates. The formula has been revised repeatedly to enhance its decorative effects and to suppress cracking or peeling. Nail polish consists of a mix of an organic polymer and several other components that give it colors and textures. Nail polishes come in all shades of color and play a significant part in manicures and pedicures.
Poly(vinyl alcohol) (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula [CH2CH(OH)]n. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in PVAc adhesive formulations, in a variety of coatings, and 3D printing. It is colourless (white) and odorless. It is commonly supplied as beads or as solutions in water. Without an externally added crosslinking agent, PVA solution can be gelled through repeated freezing-thawing, yielding highly strong, ultrapure, biocompatible hydrogels which have been used for a variety of applications such as vascular stents, cartilages, contact lenses, etc..
Ethylene-vinyl acetate (EVA), also known as poly (PEVA), is the copolymer of ethylene and vinyl acetate. The weight percent of vinyl acetate usually varies from 10 to 40%, with the remainder being ethylene. There are three different types of EVA copolymer, which differ in the vinyl acetate (VA) content and the way the materials are used.
An enteric coating is a polymer barrier applied to oral medication that prevents its dissolution or disintegration in the gastric environment. This helps by either protecting drugs from the acidity of the stomach, the stomach from the detrimental effects of the drug, or to release the drug after the stomach. Some drugs are unstable at the pH of gastric acid and need to be protected from degradation. Enteric coating is also an effective method to obtain drug targeting. Other drugs such as some anthelmintics may need to reach a high concentration in a specific part of the intestine. Enteric coating may also be used during studies as a research tool to determine drug absorption. Enteric-coated medications pertain to the "delayed action" dosage form category. Tablets, mini-tablets, pellets and granules are the most common enteric-coated dosage forms.
Hot-melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly sold as solid cylindrical sticks of various diameters designed to be applied using a hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which the user pushes through the gun either with a mechanical trigger mechanism on the gun, or with direct finger pressure. The glue squeezed out of the heated nozzle is initially hot enough to burn and even blister skin. The glue is sticky when hot, and solidifies in a few seconds to one minute. Hot-melt adhesives can also be applied by dipping or spraying, and are popular with hobbyists and crafters both for affixing and as an inexpensive alternative to resin casting.
Bis[2,4,5-trichloro-6-(pentyloxycarbonyl)phenyl]oxalate is a solid ester whose oxidation products are responsible for the chemiluminescence in a glowstick. It can be synthesized by reacting 2-carbopentoxy-3,5,6-trichlorophenol with oxalyl chloride.
Glatiramer acetate, sold under the brand name Copaxone among others, is an immunomodulator medication used to treat multiple sclerosis. Glatiramer acetate is approved in the United States to reduce the frequency of relapses, but not for reducing the progression of disability. Observational studies, but not randomized controlled trials, suggest that it may reduce progression of disability. While a conclusive diagnosis of multiple sclerosis requires a history of two or more episodes of symptoms and signs, glatiramer acetate is approved to treat a first episode anticipating a diagnosis. It is also used to treat relapsing-remitting multiple sclerosis. It is administered by subcutaneous injection.
Cellulose acetate phthalate (CAP), also known as cellacefate (INN) and cellulosi acetas phthalas, is a commonly used polymer phthalate in the formulation of pharmaceuticals, such as the enteric coating of tablets or capsules and for controlled release formulations. It is a cellulose polymer where about half of the hydroxyls are esterified with acetyls, a quarter are esterified with one or two carboxyls of a phthalic acid, and the remainder are unchanged. It is a hygroscopic white to off-white free-flowing powder, granules, or flakes. It is tasteless and odorless, though may have a weak odor of acetic acid. Its main use in pharmaceutics is with enteric formulations. It can be used together with other coating agents, e.g. ethyl cellulose. Cellulose acetate phthalate is commonly plasticized with diethyl phthalate, a hydrophobic compound, or triethyl citrate, a hydrophilic compound; other compatible plasticizers are various phthalates, triacetin, dibutyl tartrate, glycerol, propylene glycol, tripropionin, triacetin citrate, acetylated monoglycerides, etc.
Modified-release dosage is a mechanism that delivers a drug with a delay after its administration or for a prolonged period of time or to a specific target in the body.
Tygon is a brand name for a family of flexible polymer tubing consisting of a variety of materials to be used "across a range of specialized fluid transfer requirements". The specific composition of each type is a trade secret. Some variants have multiple layers of different materials. Tygon is a registered trademark of Saint-Gobain Corporation. It is an invented word, owned and used by Saint-Gobain and originated in the late 1930s. Tygon products are produced in three countries, but sold throughout the world. Tygon tubing is used in many markets, including food and beverage, chemical processing, industrial, laboratory, medical, pharmaceutical, and semiconductor processing. There are many formulations of clear, flexible, Tygon tubing. The chemical resistance and physical properties vary among the different formulations, but the tubing generally is intended to be "so resistant to chemical attack that it will handle practically any chemical", whether liquid, gas, or slurry. While largely non-reactive, Tygon has been reported to liberate carbon monoxide and is listed among carbon monoxide-releasing molecules.
Thin-film drug delivery uses a dissolving film or oral drug strip to administer drugs via absorption in the mouth and/or via the small intestines (enterically). A film is prepared using hydrophilic polymers that rapidly dissolves on the tongue or buccal cavity, delivering the drug to the systemic circulation via dissolution when contact with liquid is made.
1,3-Indandione (sometimes simply indanedione) is an organic compound with the molecular formula C6H4(CO)2CH2. It is a β-diketone on an indane framework. It is a colorless or white solid although samples can appear yellowish or even green. It is a widely used building block
A film coating is a thin polymer-based coat applied to a solid pharmaceutical dosage form such as a tablet. The thickness of such a coating is typically between 20-100 µm. It is possible to follow the dynamic curing effect on tablet coating structure by using non-destructive analytical methodologies.
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