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Functional poly (ester-anhydride) microspheres

Jaszcz K., Łukaszczyk J.

Polish Journal of Applied Chemistry

2009

Vol. 53, nr 1

1-7

Functional microspheres were prepared from poIy(ester-anhydride)s with allyl pendant groups, using a solvent removal technique. The poly(ester-anhydride)s were obtained by polycondensation of sebacic acid (SBA) and oligo(3-allyloxy-l,2-propylene succinate) terminated with carboxyl groups (OSAGE). The SBA and OSAGE content influenced the characteristics of poly(ester-anhydride)s and microspheres. The poly(ester-anhydride)s differed with their solubility and thermal properties as well as their degradation rate and mode. Stable microspheres with size in the range of 15-60 nm were obtained from poly(ester-anhydride)s containing more than 60% SBA. The microspheres obtained from po!y(ester-anhydride)s containing 60% SBA had tendency to aggregation. Microspheres were not obtained when content of SBA in poly(ester-anhydride)s was lower than 60%. All particles were spherical, however those prepared from polymers containing 90 or 80% SBA possessed smoother surfaces when compared to those prepared from poly(ester-anhydride)s containing 70 or 60% SBA. Ability of poIy(ester-anhydride)s to be formulated as microspheres would enable their eventual use in drug delivery systems.

Otrzymywanie i modyfikacja biodegradowalnych poliestrów multifunkcjonalnych

Jaszcz K., Łukaszczyk J.

Polimery

2008

T. 53, nr 3

176-181

Multifunkcjonalne poliestry (polibursztyniany) zawierające w łańcuchach bocznych grupy allilowe otrzymywano metodą katalizowanej poliaddycji bezwodnika bursztynowego (SA) z eterem allilowo-glicydylowym (AGE) i eterem butylowo-glicydylowym (BGE). Grupy allilowe w łańcuchach bocznych poliestrów utleniano do grup hydroksylowych (otrzymywanie dioli) lub do grup karboksylowych. Utlenianie do dioli prowadzono dwiema metodami: (1) przy użyciu KMnO4 w obecności NaHCO3 lub (2) z zastosowaniem tlenku N-metylomorfoliny (NMO) i katalizatora OsO4. Utlenianie do grup karboksylowych realizowano w układzie dwufazowym w obecności eteru koronowego. Jako utleniacz stosowano KMnO4 w środowisku kwasu octowego. Budowę produktu potwierdzono metodą 1H NMR. Utlenione poliestry, w porównaniu z ich nieutlenionymi prekursorami, były bardziej hydrofilowe. Poliestry zawierające ponad 60% merów z grupami -OH lub 80% merów z grupami -COOH całkowicie rozpuszczały się w wodzie.

Multifunctional polyesters containing allyl groups in side chains were synthesized by catalyzed polyaddition of succinic anhydride (SA) with allyl glycidyl ether (AGE) and butyl glycidyl ether (BGE) (Table 1). The allyl groups in side chains were oxidized to hydroxyls (syntheses of diols, Table 3) or to carboxyl groups (Table 4). Use of either KMnO4 in the presence of NaHCO3 (1) or N-methylmorpholine oxide (NMO) and OsO4 as a catalyst (2) carried out the oxidation reactions to diols. The oxidation reactions to carboxyl groups were carried out in diphase system in the presence of crown ether. KMnO4 in acetic acid was used as an oxidant. The structures of the products have been confirmed by 1H NMR method (Fig. 1). Oxidized polyesters were more hydrophilic than their non-oxidized precursors (Table 2). The polyesters containing more than 60% of mers with -OH groups or 80% of mers with -COOH groups were completely soluble in water.