Synthesis of Nylon 6,10
Background and Application.
Polymers are large molecules made up by joining together many small
molecules. The small molecules that go into making a polymer are called monomers.
When just two monomers join together the product is called a dimer. When three,
link together, a trimer. What would a molecule be called that is made up of 4
molecues? 5 ? 6? Oligomers are medium sized molecules usually made from 8 to
about 20 molecules.
Polymers can be made up from between about 20 and 10,000 monomers or
more. Polymers make up a large bulk of the commercially important organic
chemicals.
When a polymer is made up entirely of one monomer, it is called a homopolymer.
One example is polyethylene which is made up of many ethylene units joined
together. Polyethylene is the most common polymer used in the world. All plastics
products marked with a 2 inside a triangle are made of polyethylene.
As you have seen previously, a condensation reaction is a reaction where two (or
more) molecules join together to form one larger molecule and a small molecule
typically water being produced as a side product. In today’s reaction the small side
product molecule is not water but HCl. Hence, this reaction should be done in the
hood, and the product rinsed in sodium bicarbonate water to neutralize the acid
before handling.
In this reaction 1,6-hexanediamine or 1,6-diaminohexane (also commonly called
hexamethylene diamine) is reacted with sebacoyl chloride (also called decadioyl
chloride). Both amine ends of the 1,6-diaminohexane react with both acid chloride
ends of the sebacoyl chloride to form new amide linkages. The polymer which forms
is made up of alternating 1,6-diaminohexane and sebacoyl groups. This is called an
alternating copolymer. This particular Nylon is made of units of 6 carbons between
two nitrogen atoms, an amide linkage, an another unit of 10 carbons. This repeats
many many times; therefore this is Nylon-6,10.
Nylon is used in a wide variety of household product including stockings,
windbreakers, shoestrings, car parts, tents, and fishing poles.
SAFETY
Sebacoyl Chloride reacts with water immediately to form HCl gas. Sebacoyl
Chloride caused severe burns upon contact. Keep away from skin, eyes and clothes.
Sebacoyl Chloride is a lachrymator. This means it causes severe irritation to the
eyes and results in prolific tearing and pain. Wear goggles at all times during this
experiment. If any bodily contact is made with Sebacoyl Chloride, wash with copious
amounts of water immediately.
Chlorinated hydrocarbons tend to be toxic. Keep methylene chloride away from
skin.
REACTION
PROCEDURE
Work with a partner. Obtain two 50 mL beakers. Be sure these are very
clean. Wash with soap and water, then acetone if necessary. Label one beaker
“W” for water based. Label the other “M” for methylene chloride based.
Into the “M” beaker place 12 mL (two 6 mL pumps) of methylene chloride
(dichloromethane).
Carefully, while wearing gloves, fill pre-marked pipette to line (~ 0.5 mL)
with sebacoyl chloride. Dispense immediately into beaker containing methylene
chloride. Dispose of pipette in large beaker in hood marked “Used Sebacoyl
Chloride Pipettes”. Swirl “M” beaker to mix.
Into other “W” beaker place 6 mL (1 pump) of 1,6-diaminohexane solution
in water.
Bring both beakers and a copper hook and a wooden stick to any other
open hood space.
Water is less dense than methylene chloride (1.0g/mL vs 1.3 g/mL). It is
desired to layer the 1,6-diaminohexane in water on top of the sebacoyl chloride in
the methylene chloride. To do this, slowly pour the contents of the “W” beaker
down the inside of the “M” beaker with minimal mixing. There should be two
definite layers. Set the beaker down on the floor of the hood.
The nylon forms spontaneous at the interface of the two liquids.
Work with partner on next step. One person will hook the nylon which
forms at the interface with a copper hook and pull slowly straight up as high as
possible. The second person uses a wooden stick and grabs a portion of nylon
string and pulls as high as they can go. Repeat until no more nylon forms.
Another alternative to this method is for the first person to pull the nylon
and wrap it on a 100 mL graduated cylinder. Then the cylinder is rotated and the
nylon strand is coiled around the cylinder.
Dunk formed nylon into sodium bicarbonate solution to neutralize any
hydrochloric acid. Dry on paper towel. Feel free to take home or tape in lab
notebook.
CLEANUP
Dispose of residual liquid from “M” beaker into halogenated organic liquid
waste container. Dispose of residual liquid from “W” beaker into Aqueous liquid
waste container. Replace copper hook on back bench. Wipe work area down
with wet sponge. Wash hands.
Revised November 18, 2013 S. L. Weaver
Identification and uses for plastics and recycled plastics
Plastic
Identification
Code
Name of
plastic
Structure of Monomer and Polymer
polyethylene
terephthalate
PET
OH
H2C
HO
HO
H3C
high density
polyethylene
HDPE
CH2
O
C
H2
H2C
unplasticised
polyvinyl chloride
UPVC
C
H2
CH2
O
O
O
C
C
O
O
C
C
H2
C
H3C
C
H2
CH2
Soft drink and mineral water bottles,
filling for sleeping bags and pillows,
textile fibers.
Soft drink bottles, (multi-layer) detergent
bottles, clear film for packaging, carpet
fibers, fleecy jackets.
Very common plastic, usually
white or colored.
Crinkly shopping bags, freezer bags, milk
and cream bottles, bottles for shampoo
and cleaners, milk crates.
Compost bins, detergent bottles, crates,
mobile rubbish bins, agricultural pipes,
pallets, curbside recycling crates.
Hard rigid plastic, may be
clear.
Clear cordial and juice bottles, blister
packs, plumbing pipes and fittings.
Detergent bottles, tiles, plumbing pipe
fittings.
Flexible, clear, elastic plastic.
Garden hose, shoe soles, blood bags and
tubing.
Hose inner core, industrial flooring.
Soft, flexible plastic.
Lids of ice-cream containers, garbage
bags, garbage bins, black plastic sheet.
Film for builders, industry, packaging and
plant nurseries, bags.
Hard, but flexible plastic many uses.
Ice-cream containers, potato crisp bags,
drinking straws, hinged lunch boxes.
Compost bins, curbside recycling crates,
worm factories.
Rigid, brittle plastic. May be
clear, glassy.
Yoghurt containers, plastic cutlery,
imitation crystal “glassware”.
Clothes pegs, coat hangers, office
accessories, spools, rulers, video/CD boxes.
Foamed, lightweight, energy
absorbing, thermal insulation
Hot drink cups, takeaway food
containers, meat trays, packaging.
n
H2
C
CH3
n
H2
C
H3C
HC
CH2
CH
CH3
n
Cl
H2C
CH2
H2
C
H3C
C
H2
CH3
n
polypropylene PP
H2
C
H3C
HC
CH2
CH
CH3
n
H3C
polystyrene PS
Clear tough plastic, may be
used as a fiber.
Cl
Cl
low density
polyethylene
LDPE
Some uses for plastic made from
recycled waste plastic
CH3
CH
Cl
plasticised
polyvinyl
chloride
PPVC
Some uses for virgin plastic
n
H3C
HC
OH
Description
CH3
H
C
CH2
H2
C
H2
C
H2
C
CH
CH3
n
EPS, expanded
Polystyrene
other
Includes all other plastics, including acrylic
and nylon.