20 июня, 2015 
Malyar Modifiers are species that contain a labile atom (most usually hydrogen or halogen) which can be abstracted by the propagating chain.
Propagation of the chain is terminated and the radical is transferred to the modifier.
R — f CH — CHxT — CH2 — CHX + R — H L Jn
R — f CH — CHx4- CH2 — CH2X + R L -*п
Figure 1-13
The modifier radical can then act in one of two ways:
a) It can act to initiate the propagation of a new polymer chain. The net result in this case is that the modifier has acted as an agent in the transfer of the radical from one propagating chain to another. Examples of such “Chain Transfer Agents” (СТА) are carbon tetrabromide, ethane thiol and tertiary butyl mercaptan.
or
b) It can form a stabilising free radical which will not take part in further initiation reactions. In effect, the free radical has been removed from the system, and the modifier has acted as a polymerisation inhibitor. Examples of such “Inhibitors” are hydroquinone and nitrobenzene.
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