Determination of polyethylene glycol

Polyethylene glycols and total ethoxylate active may be determined by 

An alternative method, which is quicker and easier to carry out, is to 

Prepare an ion-exchange column containing about 40 meq of a strongly acidic cation-exchange resin in the acid form, in methanol. 

Pass the solution through the column at not more than 2 ml/min/cm, collecting the effluent in a tared beaker. 

Wash the column with three bed-volumes of methanol, collecting the effluent in the same beaker. 

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Jia ZQ, Tian CN. Quantitative determination of polyethylene glycol with modified Dragendorff reagent method. Desalination 2009 247(l-3) 423-9. 

No.l2,Dec.l990,p. 1597-9 FOURIER TRANSFORM IR SPECTROMETRIC DETERMINATION OF POLYETHYLENE GLYCOL (ANTISTATIC AGENT) IN HDPE Kumar T... 

Kumar [108] described a GC method for the determination of polyethylene glycol in high-density polyethylene. 

Fatty acid ethoxy lates determination of polyethylene glycols free fatty acid and mono- and diester... 

ISO 2268 1 2 Surface active agents (non-ionic)— Determination of polyethylene glycols and non-ionic active matter (adducts)— Weibull method. International Organization for Standardization, Geneva. 

Procedure Determination of Polyethylene Glycol in Ethoxylated Products by Extraction (19)... 

International Organization for Standardization, Nonionic surface active agents—poly-ethoxylated derivatives—determination of polyethylene glycol, ISO 2268 1972. Geneva, Switzerland. 

IR analysis can also be used quantitatively to determine the EO-PO ratio [12]. Using mixtures of polyethylene glycol and polypropyene glycol as calibration standards, the ratio of two absorbances, one due to the methyl group of the PO unit (e.g., the C-H stretch band at 2975 cm ) and one due to the methylene group (e.g., the C-H stretch band at 2870 cm ), are plotted against percent of PO content. The ratio of the same two absorbances taken from the IR spectrum of a poloxamer may then be used to determine its percent of PO content by interpolation. 

Note Soluble recombinant interleukin-2 (IL-2) was modified with various lengths of polyethylene glycol (PEG) polymers with average molecular weight listed. The final PEG to IL-2 ratio is listed as molar ratio, and their respective hydrodynamic size was determined based on their sendimentation coefficient. Hence the molecular weight listed in Effective Size is not the sum of the PEG and IL-2 with consideration of molar ratio of the PEG-IL-2 conjugates. 

Shanbhag, V.P. and Axelsson, C.-G. 1975. Hydro-phobic interaction determined by partition in aqueous two-phase systems. Partition of proteins in systems containing fatty acid esters of polyethylene glycol). Eur. J. Biochem. 60 17-22. 

To determine trace components in arsenic trichloride the inlet portion of the column was filled with 15% of tricresyl phosphate on Chromosorb W [47]. In this portion arsenic trichloride was completely retained as a result of the formation of a stable complex with tricrysyl phosphate. The trace components were separated in the remainder (main portion) of the column packed with 10% of polyethylene glycol 400 (PEG-400). 

Molecular weight of polyethylene glycol can be calculated by dividing the measured hydroxyl number by 34 (Molecular weight = 34/OH) A typical calibration ranges from 31-137 OH number with an SEE of 0.15 and anr of 0.998. Samples were run on a filter instrument in a65°C thermostated transflectance cell. Table 27.2 shows lab versus Infra Alyzer-predicted results for polyethylene glycol molecular weight determination and OH determination. 

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