Experiment 25:

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Experiment 25:
ORGANIC POLYMERS:
THE SYNTHESIS OF NYLON
Objectives:


To synthesize Nylon 6,10 from
hexamethylene diamine and sebacoyl
chloride.
To determine the length of the Nylon
formed using a simple mathematical
calculation.
SYNTHESIS OF AN AMIDE
O
H
R
+
N
H
amine
C
R
catalyst
R
H
O
N
C
R
+
H2O
HO
Carboxylic
Acid
amide
Reacting a carboxylic acid with an amine
yields an amide. Water is a by-product,
and this reaction is slow without a
catalyst.

SYNTHESIS OF AN AMIDE
O
H
R
+
N
H
amine
C
R
R
H
O
N
C
R
+
HCl
Cl
Acid chloride
amide
By using a carboxylic acid chloride, a
more reactive carboxylic acid derivative,
the rate of reaction can be increased. In
this reaction, HCl is the by-product.

MECHANISM
O
+
C
R
Cl
R'
H
O
N
C
H
R
O
+ OH
Cl
N
R'
H
C
R
Cl
N
R'
H
H
O
C
R
H
N
R'
SYNTHESIS OF NYLON 6,10
H
H
N
H
O
CH2CH2CH2CH2CH2CH2 N
Hexamethylene
diamine
O
C
H
Cl
CH2CH2CH2CH2CH2CH2CH2CH2 C
Sebacoyl
chloride
Cl
In order to make a polyamide, such as Nylon 6,10,
the amine molecule must have a –NH2 group at each
end, and the acid chloride must have a –COCl group
at each end.

The diamine and the diacid chloride bond together,
end-on-end, to form very long chains.

Nylon 6,10 is made from hexamethylene diamine
(the diamine) and sebacoyl chloride (the diacid
chloride).

SYNTHESIS OF NYLON 6,10
O
H
H
N
CH2CH2CH2CH2CH2CH2 N
C
+
H
H
O
CH2CH2CH2CH2CH2CH2CH2CH2 C
Cl
Cl
Hexamethylene
diamine
Sebacoyl
chloride
O
H
N
CH2CH2CH2CH2CH2CH2
H
N
C
Nylon 6,10 =
O
CH2CH2CH2CH2CH2CH2CH2CH2
H
N
H
(CH2)6 N
n
C
H
N
CH2CH2CH2CH2CH2CH2
O
O
C
(CH2)8 C
n
H
N
+
HCl
CLASSIFICATIONS OF
SYNTHETIC POLYMERS

Synthetic polymers are classified by their
method of synthesis.
Synthetic Method
Chain-growth
Step-growth
polystyrene
Polyamides (nylon)
NATURAL ORGANIC POLYMERS

Proteins


Polysaccharides


hair, skin, tissue
cellulose, starch
Polynucleotides

DNA, RNA
SYNTHETIC ORGANIC POLYMERS





Nylons
Polyesters
Acrylics
Polyvinyls
 Plastic sheeting and plumbing
materials
Polystyrenes
 Insulating materials
EXPERIMENTAL PROCEDURE
(Synthesis)




Pour diamine solution and diacid
chloride in separate beakers.
Using forceps, grasp the film
that forms at the interface of
the two liquids.
Pull up slowly and wrap end of
nylon string around a test tube.
Rotate the tube and count the
number of revolutions made
before no more nylon can be
produced.
EXPERIMENTAL PROCEDURE
(Analysis)

Calculate the length of the nylon string
produced (in meters) using the following
equation:
Nylon produced (m) =
(test tube diameter (m)) X (p) X (# test tube revolutions )
Table 25.1
Test tube diameter (mm)
# of test tube revolutions
Length of nylon (m)
SAFETY CONCERNS

CAUTION:
All chemicals are hazardous to
the skin and eyes. Safety
goggles and gloves are required
during the experiment!!!
WASTE MANAGEMENT

Pour all waste from synthesis and
solubility tests into container labeled
“ORGANIC WASTE (Polymers)”
CLEANING


Clean all glassware with soap, water,
brush, and rinse with wash acetone
before returning to lab drawer!
DO NOT return any glassware to lab
drawer dirty or wet!
LABORATORY NOTEBOOK
(Pre-lab)
• OBJECTIVE
(Must clearly state…)
• What compounds will be made and how
• What you will do with the compound once made
• CHEMICAL EQUATION
• Include the chemical equation middle of page 212.
• TABLE OF PHYSICAL DATA
(Complete the following table using
MSDS sheets from http://hazard.com/msds or www.chemexper.com ONLY. Wikipedia is
unacceptable.)
Compound
Sebacoyl chloride
Hexamethylene diamine
Sodium hydroxide
Hexane
MW (g/mol) mp(oC)
bp(oC)
d
(g/mL)
X
X
HAZARDS
X
X
X
• REFERENCE TO PROCEDURE
• full title including edition and author names
(Must include…)
• page numbers where actual procedure can be found
LABORATORY NOTEBOOK
(In-lab)
• DATA/CALCULATIONS
•
•
•
Diameter of test tube
# revolutions
Length of nylon produced calculation
• EXPERIMENTAL PROCEDURE
•
•
•
•
In paragraph form, BRIEFLY describe the procedure that you actually
followed during the lab.
Paragraph must be written in PAST TENSE, PASSIVE VOICE.
Include any volumes or weights of chemicals used during the
experiment.
Include any mistakes, accidents or observations if applicable.
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