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In polymer chemistry the kinetic chain length of a polymer, ''ν'', is the average number of monomers during polymerization. During this process, a polymer chain is formed when units called monomers are bonded together to form longer chains known as polymers. Kinetic chain length is defined as the average number of monomer units consumed for each radical initiator that begins the polymerization of a chain and is a more general development of the average degree of polymerization. The kinetic chain length can be calculated several ways, and its value can describe certain characteristics of the material, including chain mobility, glass-transition temperature, and modulus of elasticity. ==Calculating chain length== For chain-growth polymerization, the average kinetic chain length is defined as the ratio of the number of propagation steps to the number of initiation steps: : where Rp is the rate of propagation, Ri is the rate of initiation of polymerization, and Rt is the rate of termination of the polymer chain. The second form of the equation is valid at steady-state polymerization, as the chains are being initiated at the same rate they are being terminated (Ri = Rt).〔Hiemenz, Paul C., and Timothy P. Lodge. Polymer Chemistry. 2nd ed. Boca Raton, FL: CRC Press, 2007. 94-96.〕 An analogous equation can be written for living polymerization, a type of addition polymerization, and is usually written as: : where ()0-() represents the number of monomer units consumed, and ()0 the number of radicals that initiate polymerization. When the reaction goes to completion, ()=0, and then the kinetic chain length is equal to the number average degree of polymerization of the polymer. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kinetic chain length」の詳細全文を読む スポンサード リンク
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