ISSN:
1573-9171
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Conclusions 1. Polyethylenimine (PEI) was fractionated by three different methods: fractional precipitation, fractional extraction of the sulfate, and successive elution of the polymer adsorbed on Sephadex resin. 2. High-molecular PEI is characterized by a bimodal molecular weight distribution: ~2/3 is comprised of fractions with low-molecular weights, and 1/3 of fractions with mol. wt. 40–120 thousand. Low-molecular PEI, produced by acid polymerization of ethylenimine, is characterized by a narrow molecular weight distribution. 3. The Kuhn-Mark-Hauwink functions were obtained for solutions of PEI in abs. alcohol and a 0.1 N solution of NaCl in the interval of molecular weights from 1000 to 120,000.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00859999
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