Poly(vinyl alcohol) Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSER BIS WEISSER FESTSTOFF IN VERSCHIEDENEN FORMEN.
PHYSIKALISCHE GEFAHREN
Staubexplosion der pulverisierten oder granulierten Substanz in Gemischen mit Luft möglich. Fließen, Schütten o.ä. kann zu elektrostatischer Aufladung führen.
CHEMISCHE GEFAHREN
Zersetzung beim Erhitzen und beim Verbrennen unter Bildung giftiger Rauche. Reagiert mit Oxidationsmitteln und starken Säuren.
ARBEITSPLATZGRENZWERTE
TLV nicht festgelegt (ACGIH 2005).
MAK nicht festgelegt (DFG 2005).
INHALATIONSGEFAHREN
Nur ungenügende Angaben vorhanden über die Geschwindigkeit, mit der eine gesundheitsschädliche Konzentration in der Luft beim Verdampfen bei 20°C erreicht wird.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Reizt möglicherweise mechanisch.
LECKAGE
Persönliche Schutzausrüstung: Atemschutzgerät, P1-Filter für inerte Partikel. Verschüttetes Material in geeigneten Behältern sammeln. NICHT in die Umwelt gelangen lassen.
R-Sätze Betriebsanweisung:
R23/24/25:Giftig beim Einatmen, Verschlucken und Berührung mit der Haut.
R36/38:Reizt die Augen und die Haut.
R39/23/24/25:Giftig: ernste Gefahr irreversiblen Schadens durch Einatmen, Berührung mit der Haut und durch Verschlucken.
S-Sätze Betriebsanweisung:
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S24/25:Berührung mit den Augen und der Haut vermeiden.
Verwenden
NaA zeolite particles have been dispersed in a poly(vinyl alcohol) matrix to prepare a mixed-matrix membrane to study the pervaporative separation of water-butanol mixtures. Poly (vinyl alcohol)/gelatin based biocompatible polymeric scaffolds have been used to design for 3D cancer models.
Definition
ChEBI: Polyvinyl alcohol is a homopolymer macromolecule obtained by polymerisation of vinyl alcohol. It is used as a pharmaceutic aid and ophthalmic lubricant as well as in the manufacture of surface coatings artificial sponges, cosmetics, and other products.
Vorbereitung Methode
Polyvinyl alcohol is produced through the hydrolysis of polyvinyl
acetate. The repeating unit of vinyl alcohol is not used as the starting
material because it cannot be obtained in the quantities and purity
required for polymerization purposes. The hydrolysis proceeds
rapidly in methanol, ethanol, or a mixture of alcohol and methyl
acetate, using alkalis or mineral acids as catalysts.
Allgemeine Beschreibung
Polyvinyl alcohol (PVOH) is a hydrophilic linear polymer which forms copolymers of vinyl alcohol and vinyl acetate. Hence, the structural properties of polyvinyl alcohol polymers depend on the extent of polymerization and hydrolysis. Such changes cause both chemical and physical modifications such as esterification, etherification, crystallization, ion-polymer complexation in the polymer. Modified- PVOH structures are useful in biomedical applications.
Pharmazeutische Anwendungen
Polyvinyl alcohol is used primarily in topical pharmaceutical and
ophthalmic formulations. It is used as a stabilizing
agent for emulsions (0.25–3.0% w/v). Polyvinyl alcohol is also used
as a viscosity-increasing agent for viscous formulations such as
ophthalmic products. It is used in artificial tears and contact lens
solutions for lubrication purposes, in sustained-release formulations
for oral administration, and in transdermal patches. Polyvinyl
alcohol may be made into microspheres when mixed with a
glutaraldehyde solution.
Industrielle Verwendung
Polyvinyl alcohol is a tough, whitish polymerthat can be formed into strong films, tubes, andfibers that are highly resistant to hydrocarbonsolvents. Although polyvinyl alcohol is one ofthe few water-soluble polymers, it can be renderedinsoluble in water by drawing or by theuse of cross-linking agents.
Sicherheitsprofil
Questionable
carcinogen with experimental carcinogenic
and tumorigenic data by implant route.
Flammable when exposed to heat or flame;
can react with oxidizing materials. Slight
explosion hazard in the form of dust when
exposed to flame. To fight fire, use alcohol
foam, CO2, dry chemical. When heated to
decomposition it emits acrid smoke and
irritating fumes.
Sicherheit(Safety)
Polyvinyl alcohol is generally considered a nontoxic material. It is
nonirritant to the skin and eyes at concentrations up to 10%;
concentrations up to 7% are used in cosmetics.
Studies in rats have shown that polyvinyl alcohol 5% w/v
aqueous solution injected subcutaneously can cause anemia and
infiltrate various organs and tissues.
(mouse, oral): 14.7 g/kg
(rat, oral): >20 g/kg
Lager
Polyvinyl alcohol is stable when stored in a tightly sealed container
in a cool, dry place. Aqueous solutions are stable in corrosionresistant
sealed containers. Preservatives may be added to the
solution if extended storage is required. Polyvinyl alcohol undergoes
slow degradation at 100°C and rapid degradation at 200°C; it
is stable on exposure to light.
Inkompatibilitäten
Polyvinyl alcohol undergoes reactions typical of a compound with
secondary hydroxy groups, such as esterification. It decomposes in
strong acids, and softens or dissolves in weak acids and alkalis. It is
incompatible at high concentration with inorganic salts, especially
sulfates and phosphates; precipitation of polyvinyl alcohol 5% w/v
can be caused by phosphates. Gelling of polyvinyl alcohol solution
may occur if borax is present.
Regulatory Status
Included in the FDA Inactive Ingredients Database (ophthalmic
preparations and oral tablets). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable
Non-medicinal Ingredients.
Poly(vinyl alcohol) Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
