chem 問題 星期2考..plx教我

There are different cases for condensation polymerization.

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Case 1: Two monomers, and each monomer has two identical functional groups to form the polymer.

This is the commonest type. The general equation (unbalanced) is:
A-█-A + B--B → (-█--)n + AB

Example 1: polyester
Monomers: HOOC-C6H4-COOH and HO-CH2CH2-OH
Polymer formed: (-OC-C6H4-CO-O-CH2CH2-O-)n
Molecule eliminated: H2O

Example 2: nylon 6,6
Monomers: ClCO-(CH2)4-COCl and HNH-(CH2)6-HNH
Polymer formed: (-CO-(CH2)4-CO-NH-(CH2)6-NH-)n
Molecule eliminated: HCl

An alternative version of Example 2: nylon 6,6
Monomers: HOCO-(CH2)4-COOH and HNH-(CH2)6-HNH
Polymer formed: (-CO-(CH2)4-CO-NH-(CH2)6-NH-)n
Molecule eliminated: H2O

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Case 2: Two monomers, one has two functional groups, and another has only one.

The general equation (unbalanced) is:
A-█-A + B= → (-█--)n + AB

A typical example is urea-methanl.
Monomers: HNH-CO-HNH (urea) and O=CH2 (methanal)
Polymers formed: (-NH-CO-NH-CH2-)n
Molecule eliminated: H2O
(Cross linkages are formed when the polymer is heated.)

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Case 3: One monomer, which has two different functional groups.

The general equation (unbalanced) is:
A-█-B → (-█-)n + AB

A typical example is nylon 6.
Monomer: HOOC-(CH2)5-HNH or ClOC-(CH2)5-HNH
Polymer formed: (-OC-(CH2)5-NH-)n
Molecule eliminated: H2O or HCl
(depending on which monomer is used.)

case1: 兩個compound,各自有1個funtional group,那麼便OK,
CASE2 :一個compound入面,有兩個funtional group,那麼都OK~
其他的,等你讀上去再學~~