By Professor M. B. Neiman (auth.), Professor M. B. Neiman (eds.)
The desire for a large improvement of the creation of polymer ma terials has turn into obtrusive. these types of fabrics are topic to numerous forms of getting older (destruction); for that reason, stabilizers which enable the stor age, reprocessing, and use of polymer fabrics with none appreci capable switch of their houses has to be brought into them. in recent times, this challenge of stabilizing polymers has attracted the eye of many scientists and technologists, either within the USSR and overseas. The clinical foundation of the international stories can be present in a couple of theo retical premises, yet mainly the idea of chain reactions with un branched chains. within the Soviet Union, the thoughts of Academician N. N. Semenov on chain reactions with degenerate branches became the start line of theoretical experiences of the stabilization and destruction of polymers. Soviet scientists have constructed a concept of severe concentrations of antioxidants and feature proven that the strategies of stabilization have a really complicated chemical personality. the character of the polymers them selves tremendously impacts those approaches and therefore, assorted stabil izers are required for polymers of other constructions. additionally, it's been proven that the antioxidants used so far can't purely reason chain termination, yet may also begin oxidation and provides upward thrust to de generate branches.
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Extra info for Aging and Stabilization of Polymers
It is clear that under the condition kx< q> (25) the reaction will be autoaccelerated, while under the condition (26) we shall have a steady-state reaction. Thus, the critical concentration of the antioxidant is determined by the equation x = IP/k (27) If the condition (26) is observed at the beginning of the reaction, then the concentration of radicals (Fig. 14, curve 1) reaches some steadystate value soon after the beginning of the reaction, which will be preserved for a time from zero to T. During this time the concentration x will drop comparatively slowly to a value Xcr (curve 2).
M. Emanuel', A. B. Gagarina, and Z. K. Maizus, Doklady Akad. Nauk SSSR 135:354, 1960. 61. D. Ryshavy, Vysokomolekulyarnye Soedineniya 3:464, 1961. 62. V. B. Miller, M. B. Neiman, V. S. Pudov, and L. 1. Lafer, Vysokomolekulyarnye Soedineniya 1:1696, 1959. 40 Chapter I 63. R. Goglev and M. B. Neiman, Vysokomolekulyarnye Soedineniya 5:1050, 1963. 64. G. 1. Likhtenshtein, M. B. Neiman, and N. Sysoeva, Tr. po Khim. i Khim. Tekhnol. p. 155, 1963. 65. N. M. Emanuel' and Yu. I. Lyaskovskaya, Inhibition of Processes of Fat Oxidation, Moscow, State Press for the Food Industry, 1961.
Moreover, an important role is played by the formation of hydroperoxides in the reaction of peroxide radicals R0:i with antioxidants, the molecules of which contain weakly bonded hydrogen. Such antioxidants include Widely used derivatives of phenols and aromatic amines. It seems to us that one of the most important problems in the field of inhibition of oxidation is the problem of the search for new classes of antioxidants which do not contain weakly bonded hydrogen in their molecules. Of undoubted interest in this respect are trisubstituted esters of phosphorous acid , as well as polyphenylenes, polyphenylacetylenes, and polyazophenylenes .
Aging and Stabilization of Polymers by Professor M. B. Neiman (auth.), Professor M. B. Neiman (eds.)