ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The polymerization rate of 1-methylazacyclotridecan-2-one (N-methyldodecanelactam) (1) initiated with dodecanoic acid (2) can be described within the whole range of conversions in terms of the simple relation In ([1]0/[1]) = k[2]0t, in spite of the complexity of the overall reaction scheme. The rate constants (k) determined for 240, 260, and 280°C are 0,32, 1,21, and 3,4 kg · mol-1 h-1, respectively, and the constants of the Arrhenius equation are A = 6,6 · 1013kg · mol-1 h-1, E = 140 kJ · mol-1. The resulting poly(N-methyldodecaneamide) (3) is a semicrystalline polymer (m.p. 65°C), soluble in polar organic solvents. The following constants of the Mark-Houwink equation were determined for solutions of this polyamide: for 5000 〈 M̄w 〈 150 000 g · mol-1 at 25°C in THF (2-propanol), K = 0,124 (0,161) cm3 · g-1, a = 0,59 (0,56); for 5 000 〈 M̄w 〈 80 000 g · mol-1 at ⊖-temperature = 30,5°C in 1,4-dioxane, K = 0,215 cm3 · g-1, a = 0,50. Analyses of molar masses, both theoretical and experimental (light-scattering, GPC, osmometry, end groups), indicate that at the polymerization temperature of 280°C side reactions already take place, reflected in random cleavage and in branching of chains.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1983.021841001
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