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Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula [CH 2 CH(OH)] n . It is used in papermaking , textile warp sizing , as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) adhesive formulations, in a variety of coatings, and 3D printing .
The degree of polymerization of polyvinyl acetate is typically 100 to 5000, while its ester groups are sensitive to base hydrolysis and slowly convert PVAc into polyvinyl alcohol and acetic acid. The glass transition temperature of polyvinyl acetate is between 30 and 45 °C depending on the molecular weight.
Suspension polymerization is divided into two main types, depending on the morphology of the particles that result. In bead polymerization, the polymer is soluble in its monomer and the result is a smooth, translucent bead. In powder polymerization, the polymer is not soluble in its monomer and the resultant bead will be porous and irregular. [5]
The polymer came to be known as “Super Slurper”. [10] The USDA gave the technical know-how to several US companies for further development of the basic technology. A wide range of grafting combinations were attempted including work with acrylic acid, acrylamide and polyvinyl alcohol (PVA).
Vinylon, also known as Vinalon (more common in Korean sources), is a synthetic fiber produced from reaction between polyvinyl alcohol (PVA) fiber and formaldehyde. Chemically it is polyvinyl formal (PVF). Vinylon was first developed in Japan in 1939 by Ri Sung-gi, Ichiro Sakurada, and H. Kawakami. [1]
Formvar refers to any of several thermoplastic resins that are polyvinyl formals, which are polymers formed from polyvinyl alcohol and formaldehyde as copolymers with polyvinyl acetate. They are typically used as coatings, adhesives , and molding materials.
Polyethylene glycol–polyvinyl alcohol (PEG-PVA) brand name Kollicoat IR is a multifunctional excipient [1] used as a pill binder as well as a wet binder. A typical formulation is composed of 25% polyethylene glycol (PEG) and 75% polyvinyl alcohol (PVA); where the vinyl alcohol moieties are grafted on a polyethylene glycol backbone.
The polymer is dissolved in an organic solvent (such as dichloromethane). Powdered drug and filler (typically an inert sugar) are added to the liquid solution and rapidly mixed to obtain a homogeneous mixture. The drug-filler-polymer mixture is then cast into a mold at −80 °C and freeze-dried until solid.