26 июня, 2015 
Malyar There are two primary factors influencing monomer reactivity:
a) the ease with which a monomer will form a monomer radical
b) the subsequent reactivity of the monomer radical so formed.
Both these factors are dependent on the monomer structure.
Reactivities of monomers can be compared by examination of their transfer coefficients for a specific transfer agent.
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TABLE 1-5: RATE COEFFICIENT OF TRANSFER TO TOLUENE AT 60°C
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The effect of methyl substitution is to reduce the coefficient of transfer towards toluene showing that reactivity decreases with the degree of substitution on the C atom.
Tensile strength, elongation and Tg are all related to monomer structure as illustrated in the table below:
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TABLE 1-6: TENSILE STRENGTH, ELONGATION AND Tg(°C)
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TABLE 1-7: THE EXTERIOR DURABILITY OF ACRYLIC HOMOPOLYMERS
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Acrylic resins usually contain a variety of monomers. The following table gives a general classification for monomers and helps indicate which ones are most suitable for a particular application
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TABLE 1-8: CHARACTERISTICS OF SOME ACRYLIC MONOMERS
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The table demonstrates general trends, but anomalies exist.
Acrylic acid, methacrylic acid, acrylamide and methacrylamide tend to give films with good hardness and chemical resistance.
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