We synthesized water-insoluble polymers, poly(b-cyclodextrin-co-citric acid)s, by heating a mixture of citric acid, cyclodextrin (CD), and Na 2 HPO 4 as a catalyst with a 6 : 1 : 2 molar ratio at 160, 170, and 180 C for 10 and 20 min. The chemical composition of the polyesters was determined by high pressure liquid chromatography (HPLC) analysis of the polymer hydrolysates. The crosslinking mechanisms and thermal degradation of the polymers were also investigated. The polyesters contained 30-35% citric acid, 1-4% unsaturated carboxylic acids (i.e., itaconic, cis-aconitic, trans-aconitic, and mesaconic acids), and 60-70% CD, whereas about 40% of them were able to form inclusion complexes.
Review of various methods of limitation of epoxy resins (EP), used for titled purpose, flammability is presented on the basis of wide literature data (up to 2004). Halogen containing flame-retardants have been discussed in details. The mechanisms of their actions were characterized as well as the methods of their use together with selected metal (mainly Sb) compounds. Flame-retardants based on phosphorus compounds, introduced later because of some disadvantages of halogen containing ones, were also presented. Phosphorus compounds used as EP curing agents [Formulas (I)-(VII)] as well as organic phosphorus derivatives built into EP [Formulas (XII), (XIII), (XV), (XVI), (XVIII)] were taken into consideration. Other methods of flammability limitation, among others Al(OH) 3 or Mg(OH) 2 used for this purpose, were presented. Toxicity of EP combustion products was discussed (Table 2).
Luminescence properties of a new material ‐ epoxy resin with added 9‐(2,3‐epoxypropyl)carbazole (REPK) were studied. Absorption and photoluminescence (PL) spectra of REPK are compared with those of poly(N‐vinylcarbazole) (PVK). PL in REPK is shifted to shorter wavelengths. Its intensity is higher than in PVK. REPK emits light in the range from 330 nm to 470 nm. PL spectrum of REPK could be well deconvoluted for four emission bands.
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