Polyethylene Glycol Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSE, VISKOSE, LEICHT HYGROSKOPISCHE FLüSSIGKEIT.
ARBEITSPLATZGRENZWERTE
TLV nicht festgelegt (ACGIH 2005).
MAK: (Einatembare Fraktion) 1000 mg/m? Spitzenbegrenzung: überschreitungsfaktor II(8); Schwangerschaft: Gruppe C; (DFG 2005).
INHALATIONSGEFAHREN
Eine bel?stigende Partikelkonzentration in der Luft kann beim Dispergieren schnell erreicht werden.
LECKAGE
Ausgelaufene Flüssigkeit in abgedeckten Beh?ltern sammeln. Verschüttete Flüssigkeit mit viel Wasser wegspülen.
R-S?tze Betriebsanweisung:
R36/38:Reizt die Augen und die Haut.
S-S?tze Betriebsanweisung:
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S24/25:Berührung mit den Augen und der Haut vermeiden.
Beschreibung
Polyethylene glycols are a family of linear polymers formed
by a base-catalyzed condensation reaction with repeating
ethylene oxide units being added to ethylene. The molecular
formula is (C2H4O)multH2O where mult denotes the average
number of oxyethylene groups. The molecular weight can
range from 200 to several million corresponding to the
number of oxyethylene groups. The higher-molecular-weight
materials (100 000 to 5 000 000) are also referred to as
polyethylene oxides. The average molecular weight of any
specific polyethylene glycol product falls within quite narrow
limits (°5%). The number of ethylene oxide units or their
approximate molecular weight (e.g., PEG-4 or PEG-200)
commonly designates the nomenclature of specific polyethylene
glycols. Polyethylene glycols with amolecular weight
less than 600 are liquid, whereas those of molecular weight
1000 and above are solid. These materials are nonvolatile,
water-soluble, tasteless, and odorless. They are miscible with
water, alcohols, esters, ketones, aromatic solvents, and chlorinated
hydrocarbons, but immiscible with alkanes, paraffins,
waxes, and ethers.
Chemische Eigenschaften
White waxy crystalline flakes
Verwenden
Used in conjunction with carbon black to form a conductive composite.1 Polymer nanospheres of poly(ethylene glycol) were used for drug delivery.2
Definition
Any of several condensa-tion polymers of ethylene glycol with thegeneral formula HOCH2(CH2OCH2)nCH2OH orH(OCH2CH2)nOH. Average molecular weightsrange from 200 to 6000. Properties vary with molec-ular weight.
Vorbereitung Methode
Polyethylene glycol polymers are formed by the reaction of ethylene
oxide and water under pressure in the presence of a catalyst.
Indications
Polyethylene glycol (Miralax) is another osmotic
laxative that is colorless and tasteless once it is mixed.
Allgemeine Beschreibung
Clear colorless viscous liquid.
Air & Water Reaktionen
Water soluble.
Reaktivit?t anzeigen
Poly(ethylene glycol) is heat-stable and inert to many chemical agents; Poly(ethylene glycol) will not hydrolyze or deteriorate under normal conditions. Poly(ethylene glycol) has a solvent action on some plastics.
Brandgefahr
Poly(ethylene glycol) is combustible.
Sicherheitsprofil
When heated to
decomposition it emits acrid smoke and
irritating fumes.
Environmental Fate
Like other polymeric substances, polyethylene glycols are not
readily biodegradable, with reported 5-day biochemical oxygen
demand (BOD5) of 0–1%. However, owing to their hydrophilicity,
they have a low potential to bioaccumulate.
Lager
Polyethylene glycols are chemically stable in air and in solution, although grades with a molecular weight less than 2000 are hygroscopic. Polyethylene glycols do not support microbial growth, and they do not become rancid.
Polyethylene glycols and aqueous polyethylene glycol solutions can be sterilized by autoclaving, filtration, or gamma irradiation.
Sterilization of solid grades by dry heat at 150℃ for 1 hour may induce oxidation, darkening, and the formation of acidic degradation products. Ideally, sterilization should be carried out in an inert atmosphere. Oxidation of polyethylene glycols may also be inhibited by the inclusion of a suitable antioxidant.
If heated tanks are used to maintain normally solid polyethylene glycols in a molten state, care must be taken to avoid contamination with iron, which can lead to discoloration. The temperature must be kept to the minimum necessary to ensure fluidity; oxidation may occur if polyethylene glycols are exposed for long periods to temperatures exceeding 50℃. However, storage under nitrogen reduces the possibility of oxidation.
Polyethylene glycols should be stored in well-closed containers in a cool, dry place. Stainless steel, aluminum, glass, or lined steel containers are preferred for the storage of liquid grades.
Inkompatibilit?ten
The chemical reactivity of polyethylene glycols is mainly confined to
the two terminal hydroxyl groups, which can be either esterified or
etherified. However, all grades can exhibit some oxidizing activity
owing to the presence of peroxide impurities and secondary
products formed by autoxidation.
Liquid and solid polyethylene glycol grades may be incompatible
with some coloring agents.
The antibacterial activity of certain antibiotics is reduced in
polyethylene glycol bases, particularly that of penicillin and
bacitracin. The preservative efficacy of the parabens may also be
impaired owing to binding with polyethylene glycols.
Physical effects caused by polyethylene glycol bases include
softening and liquefaction in mixtures with phenol, tannic acid, and
salicylic acid. Discoloration of sulfonamides and dithranol can also
occur, and sorbitol may be precipitated from mixtures. Plastics, such
as polyethylene, phenolformaldehyde, polyvinyl chloride, and cellulose-ester membranes (in filters) may be softened or dissolved
by polyethylene glycols. Migration of polyethylene glycol can occur
from tablet film coatings, leading to interaction with core
components.
Regulatory Status
Included in the FDA Inactive Ingredients Database (dental
preparations; IM and IV injections; ophthalmic preparations; oral
capsules, solutions, syrups, and tablets; rectal, topical, and vaginal
preparations). Included in nonparenteral medicines licensed in the
UK. Included in the Canadian List of Acceptable Non-medicinal
Ingredients.
Polyethylene Glycol Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte