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#REDIRECT [[Copolymer]]
In [[chemistry]], '''copolymerization''' is the process of using more than one [[monomer]] in the production of a [[polymer]], resulting in a product with properties different to the homopolymer of either monomer.
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== Copolymerization Equation ==
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The Mayo-Lewis equation (also called the copolymerization equation) gives the molar ratios of the two monomers M<sub>1</sub> and M<sub>2</sub> in the resulting polymer as:
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<math>\frac {d\left [M_1 \right ]}{d\left [M_2\right ]}=\frac{\left [M_1\right ]\left (r_1\left[M_1\right ]+\left [M_2\right ]\right)}{\left [M_2\right ]\left (\left [M_1\right ]+r_2\left [M_2\right ]\right)}</math>
where r<sub>1</sub> and r<sub>2</sub> are the reactivity ratios of the individual monomers and r<sub>1</sub> = k<sub>11</sub>/k<sub>12</sub> & r<sub>2</sub> = k<sub>22</sub>/k<sub>21</sub>, i.e. ''r'' = the rate of reaction with another monomer of itself / the rate of reaction with a different monomer. ''r'' is also called the copolymerization parameter.
k<sub>11</sub> and k<sub>22</sub> are the rate constants for the homopolymerization of the two monomers. k<sub>12</sub> or k<sub>21</sub> are the rate constants for the reaction between the two different monomers.
'''In another form''':
<math>F_1=1-F_2=\frac{r_1 f_1^2+f_1 f_2}{r_1 f_1^2+2f_1 f_2+r_2f_2^2}</math>
where F<sub>1</sub>, F<sub>2</sub> are the mole fractions of monomers M<sub>1</sub>, M<sub>2</sub> in copolymer:
F<sub>1</sub>=1-F<sub>2</sub>=d[M<sub>1</sub>]/(d[M<sub>1</sub>]+d[M<sub>2</sub>])
and ''f''<sub>1</sub>, ''f''<sub>2</sub> are the mole fractions of monomers M<sub>1</sub>, M<sub>2</sub> in the feed:
''f''<sub>1</sub>=1-''f''<sub>2</sub>=M<sub>1</sub>/(M<sub>1</sub>+M<sub>2</sub>)
== Examples ==
[[acrylonitrile butadiene styrene]] (ABS) [[plastic]], styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS).
== See also ==
*[[Heteropolymer]]
'''References'''
#Mayo, F. R., and Lewis, F. M., ''J. Am. Chem. Soc.'', '''66''', 1594 (1944).
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