Separations of water soluble polyethylene glycol oligomers on phenyl-bonded phase using low wavelength UV detection at 190 nm

1984 ◽  
Vol 7 (8) ◽  
pp. 494-496 ◽  
Author(s):  
S.-T. Lai ◽  
L. Sangermano ◽  
D. C. Locke
Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1915 ◽  
Author(s):  
Eyob Wondu ◽  
Hyun Woo Oh ◽  
Jooheon Kim

In this study water-soluble polyurethane (WSPU) was synthesized from isophorone diisocyanate (IPDI), and polyethylene glycol (PEG), 2-bis(hydroxymethyl) propionic acid or dimethylolpropionic acid (DMPA), butane-1,4-diol (BD), and triethylamine (TEA) using an acetone process. The water solubility was investigated by solubilizing the polymer in water and measuring the contact angle and the results indicated that water solubility and contact angle tendency were increased as the molecular weight of the soft segment decreased, the amount of emulsifier was increased, and soft segment to hard segment ratio was lower. The contact angle of samples without emulsifier was greater than 87°, while that of with emulsifier was less than 67°, indicating a shift from highly hydrophobic to hydrophilic. The WSPU was also analyzed using Fourier transform infrared spectroscopy (FT-IR) to identify the absorption of functional groups and further checked by X-ray photoelectron spectroscopy (XPS). The molecular weight of WSPU was measured using size-exclusion chromatography (SEC). The structure of the WSPU was confirmed by nuclear magnetic resonance spectroscopy (NMR). The thermal properties of WSPU were analyzed using thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).


2017 ◽  
Vol 148 (1) ◽  
pp. 438-442 ◽  
Author(s):  
Yuanjiang Zhao ◽  
Yanli Liu ◽  
Jianzhang Wei ◽  
Haiyan Fu ◽  
Xueli Zheng ◽  
...  

2019 ◽  
Vol 98 ◽  
pp. 153-160 ◽  
Author(s):  
Chunxiao Li ◽  
Juan Dai ◽  
Dan Zheng ◽  
Jingyang Zhao ◽  
Yinghua Tao ◽  
...  

2016 ◽  
Vol 40 (5) ◽  
pp. 4513-4518 ◽  
Author(s):  
Guang Li ◽  
Farong Tao ◽  
Qian Liu ◽  
Liping Wang ◽  
Zhuang Wei ◽  
...  

A novel reversible colorimetric chemosensor based on polyethylene glycol has been developed to detect Cu2+ ions in pure aqueous solution.


2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Yu-I Hsu ◽  
Atsushi Mahara ◽  
Tetsuji Yamaoka

For a water-soluble polyethylene glycol (PEG) magnetic resonance imaging (MRI) contrast agent, it has been demonstrated that the contrast efficiency was increased with increased branched structure of the contrast agent. However, the cause of enhanced contrast efficiency by the branched structure has not been clarified. Hence, we investigate the cause of the contrast agent enhancement by changing the Gd introduction ratio of the eight-arm PEG from 1.97 to 4.07; furthermore, the terminal mobility of the contrast agents with different structures was evaluated using proton nuclear magnetic resonance (1H-NMR) spectroscopy. It was shown that the relaxivity and contrast luminance of the synthesized branched PEG-Gd contrast agents are larger than those of linear PEG-Gd and commercially available contrast agents. Additionally, the change in the Gd introduction ratio did not affect the contrast efficiency. The terminal mobility results measured by NMR show that the linewidth at half height became broader with an increased number of branches, implying that the mobility of branched PEG-Gd is slower than that of linear PEG-Gd. Interestingly, the linewidth at half height of different structures did not change in an organic solvent; this phenomenon appeared specifically in water. It is suggested that the stable branched structure enabled the improvement in the relaxivity and contrast luminance.


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