Branching of chains

In (b) and (c), it can be seen that from each H atoms, two radicals O and H are produced which propagate the chain. Thus, a branching of chain occurs. When reactions proceed to some extent, the amount of free radicals would be very large and an explosion would occur. The free radicals may also be destroyed mainly by collision with the walls. 

When n >1, the branching of chain is involved. If n is large enough so that... 

Schematic representation of the structure of a giycogen molecule. Each ellipse represents a glucose residue. There is considerable branching of chains.

Once again, however, there are superposed complexities due to various competing modes of chain termination and especially to the existence of a mechanism for the branching of chains, namely ... 

Degenerate branching-chain reactions. As presented in Chapter 1, for such reactions the accumulation rate of chain carriers (n) and the intermediate product (P) responsible for the degenerate branching of chains is described by the following equations [51] ... 

Also Raman spectroscopy has greatly contributed to our knowledge of the conformational structure of polyethylene in the solid state. In the range below 250 cm there appear the so-called acoustic branches of chain vibrations from their position, the length of uninterrupted sequences of t structure can be determined by means of the expression originally proposed by Schaufele and Shimanouchi [8] ... 

The molecular chain of trigonal polyoxymethylene (-CHj-O-jp takes the 9s helical conformation [Tadokoro, Yasumoto, Murahashi, and Nitta (I960)]. There are four atoms per repeat unit of CH2O and accordingly twelve branches of chain vibrations. 

The molecular chain of poly(ethylene glycol) takes the 2 helical conformation as shown in Fig. 111.9 [Miyazawa, Fukushima, and Ideguchi (1962), Tadokoro, Chatani, Yoshihara, Tahara, and Murahashi (1964)]. There are seven atoms per repeat unit of CHjCHjO and accordingly twenty-one branches of chain vibrations. 

---