NYLON

4. OTHER NAMES
Polycaprolactam
Polyamide 6
PA6
Poly-ε-caproamide
Perlon
Capron
Ultramid
Akulon
Nylatron
Kapron
Alphalon
Tarnamid
Akromid
Frianyl
Schulamid
Durethan
Molecular formula (C6H11NO)n
Density 1.084 g/mL
Melting point 493 K
NYLON 6

5. PPRREEPPAARRAATTIIOONN OOFF NNYYLLOONN 66
•Nylon 6 is prepared from ϵ-caprolactam in the presence of
water (which acts as catalyst) and acetic acid as a molecular
weight regulator.
The typical combination is charged into the vessel and reacted
under a nitrogen blanket at 250°C for about 12 hours .

6. MMAANNUUFFAACCTTUURRIINNGG OOFF NNYYLLOONN 66
• The schematic diagrams of the continuous polymerization of ϵ-
caprolactam to produce Nylon 6 is illustrated on the side.
• The so called VK tube is used in the polyamide process.
• Reactive end groups are formed by hydrolysing the caprolactam to
ϵ amino caproic acid .
• A lactam melt with a relatively high water content (15%) is fed to
the top of the VK tube equipped with a stirrer and heating coil.
• The water vapourises at the top , when viscosity is still low , to
give a residue of the desired composition.
• In the lower part of the tube , the equilibrium degree of
polymerization is reached with an increasing viscosity of the melt.
• The polymer is drawn off at the bottom and granulated.
• Its equilibrium content of caprolactam and oligomers is about
10% at a final temperature of 270 °C..
• The monomer and oligomers are extracted from the chips with
hot water, and the polymer is subsequently dried with hot gas in a
ventricle cylinder hot dryer.
• Intensive drying can produce a further reaction in the solid state
and according to the polycondensation equilibrium a higher degree
of polymerization reached .

7. RREELLAATTIIOONNSS OOFF SSTTRRUUCCTTUURREE AANNDD
PPRROOPPEERRTTIIEESS
• In polyamides such as Nylon 4,6 , 6,6 , 6,10 and 11 contain polar –CONH- groups
spaced out at regular intervals so that the polymer crystallize with a high
intermolecular attraction . These polymer chains also have aliphatic chain segments
which give a measure of flexibility in the amorphous region.
• The combination of high inter chain attraction in crystalline zone and flexibility in the
amorphous zone leads to polymer which are tough above their apparent glass
transition temperature.
• The high intermolecular attraction leads to polymers of high melting point. However
above the melting point the melt viscosity is low because the polymer flexibility at such
high temperatures , which are usually more than 200°C above the Tg and the relatively
low molecular weight.
• Because of high cohesive energy density and their crystalline state the polymers are
soluble only in a few liquids of similar high solubility parameter which are capable of
specific interaction with the polymers.
• The electrical insulation properties are quit good at room temperature in dry conditions
and at low frequencies . Because of the polar structure they are not good insulators for
high frequency work and since they absorb water they are also generally unsuitable
under humid conditions.

8. SSTTRRUUCCTTUURRAALL VVAARRIIAABBLLEESS AAFFFFEECCTTIINNGG TTHHEE
PPRROOPPEERRTTIIEESS
 The distance between the repeating –CONH- group :
As a rule higher the amide group concentration i.e. the shorter the distance between
–CONH- group , the higher the:
• Density
• Forces required to mechanically separate the polymer molecules and hence the higher the tensile strength,
rigidity, hardness and resistance to creep.
• The Tm and heat deflection temperature
• Resistance to hydrocarbon
• Water absorption
Nylon 11, has twice the distance between amide group of that in Nylon 6, and
subsequently is intermediate in properties between Nylon 6 and polyethylene.
 The number of methylene groups in the intermediates:
Even number of methylene groups have higher melting points than similar polymers with
odd number of methylene groups .
Nylon 6,6 has a higher melting point than either nylon 5,6 or nylon 7,6. With polymers
from amino acids and lactams i.e. among nylon 6,7 and 8 it is found that Nylon 7 (227°C)has higher melting
point than either Nylon 6(215°C) or Nylon 8(180°C).
These differences are due to the differences in the crystal structure of polymers with odd
and even methylene groups which develop in oder that oxygen atoms in one molecule are adjacent to amino
group of a second molecule.
Hydrogen bond with NH-O distance 2-8 Å are produced and the reason for the high
strength and the high melting point of polyamide such as Nylon 6, 66 &7.

9.  The molecular weight:
• Specific type of Nylon,e.g.66 are frequently available in forms
differing in molecular weight. The main differences between such
grades is in melt viscosity, the more viscous grades being more
suitable for processing by extrusion techniques.
 N-substitution :
• Replacement of the hydrogen atom in the –CO-NH- groups as
̴ CH3 and ̴CH2OCH3 will cause a reduction in the inter chain
attraction and a consequent decrease in softening point. Rubbery
products may be obtained from methoxy methyl Nylons.
 Co-polymerization:
• Co-polymerization as usual, leads to less crystalline and frequently
amorphous materials . These materials as might be expected ,
are tough leather like , flexible and when unfilled reasonally
transparent.

11. Attacked by strong acids ,phenols, cresols at
elevated temperature
High temperature resistance
Low co-efficient of linear thermal expansion
High water absorption
Fatigue resistance
Good drawability
Creep resistance
Good appearance
Good moulding economies

14. OTHER NAMES
Poly(hexamethylene adipamide)
Poly(N,N-hexamethyleneadipinediamide)
Maranyl
Ultramid
Zytel
Akromid
Durethan
Frianyl
Vydyne
Molecular formula - (C12H22N2O2)n
Density – 1.14 g/mL (zytel)
Melting point - 542K

15. PREPARATION OF NYLON 66
• The Nylon 66 is prepared from Nylon salt
(prepared by reacting the hexamethylene diamine
and adipic acid in boiling methanol. The
comparatively insoluble salt precipitate out from
methanol.)
• A 60 % aqueous solution of the salt is then run into
a stainless steel autoclave together with a trace of
acetic acid to limit the molecular weight (9000-
15000).
• The vessel is sealed and purged with oxygen free
nitrogen and the temperature raised to 220 degree
celsius. A pressure of 1-7 MPa is developed.
• After 1-2 hours the temperature is raised to 270-
280 °C and steam blend off to maintain the pressure
1.7 MPa.
• The pressure is then reduced to atmospheric for
one hour , after which the polymer is extruded by
oxygen free nitrogen on to a water cooled casting
wheel to form a ribbon which is subsequently
disintegrated.

16. MANUFACTURING OF NYLON 66
• The polymerization of nylon 66 is
carried out in several different
reactors connected in series .
• The starting material is an aqueous
solution of Nylon salt (AH salt)
containing equivalent quantities of
hexamethylene diamine and adipic
acid .
• The solution with about 60% solid
content is fed in to the first horizontal
cylindrical reactor then divided in to
several components where the water
is drawn off as vapour and
precondensate of low molecular
weight is formed.

17. • This is pumped in to the second reactor , which
is a heated tube reactor with a gradually
increasing diameter. Polycondensation proceeds
here and vapour forms at falling pressure.
• The next step is the removal of water in a
steam seperator followed by feeding the polymer
melt by means of a screw conveyor in to the last
reactor,which consists of a heated screw conveyor
where water vapour is again withdrawn and the
final poly-condensation equillibrium is attained .

19. BUSSINESS EQUIPMENT
Bussiness machines
Vending machines
Office equipment
CONSUMER PRODUCTS
Kitchen utensils
Toys
Sporting goods
Apparel fitments
Personal accessories
Photographic equipment
Musical instruments
Brush bristles
Film for cooking
Fishing line

20. ELECTRICAL
Industrial controls
Wiring and associated devices
Industrial connectors
Batteries
Telephone parts
Switches
HARDWARE
Furniture fittings
Door and window fittings
Tools
Lawn and garden implements
Boat fittings

21. MACHINERY
Agricultural
Mining and oil drilling
Food processing
Printing
Textile processing
Engine parts
Pumps, valves, meters, filters
Air blowers
Material handling equipment
Standard components
Gears
Cams
Sprockets
Bearings
Gaskets
Pulleys
Brushes

22. APPLICATIONS OF NYLON 6 & 66

29. MANUFACTURERS OF PA 6 & PA 66
Monsanto St.Louis
Bayers Corpn. Polymers
BASF
Dupont India Pvt Ltd
Sri Ram Fibers(SRF)
Tipco Industries Ltd
Vimar International India (P)Ltd
Dilip Plastics (p)ltd
Ka Bee Agencies
Professional plastics industries

30. Biodegradation
Flavobacterium sp. [85] and Pseudomonas sp. (NK87)
degrade oligomers of Nylon 6, but not polymers. Certain white
rot fungal strains can also degrade Nylon 6 through oxidation.
Biodegradable Polymers aass DDrruugg CCaarrrriieerr SSyysstteemmss
◦ Natural Polymers
 Remain attractive because they are natural products of living
organism, readily available, relatively inexpensive, etc.
 Mostly focused on the use of proteins such as gelatin, collagen, and
albumin

31. NYLON COMPOSITES
Nylon can be used as the matrix material in composite materials,
with reinforcing fibers like glass or carbon fiber; such a composite has a
higher density than pure nylon. Such thermoplastic composites (25% to 30% glass
fiber) are frequently used in car components next to the engine, such as intake
manifolds, where the good heat resistance of such materials makes them feasible
competitors to metals.
AEROSPACE APPLICATION
For aerospace applications requiring specific surface properties,
composites from UHMWPE, para aramid,carbon, glass, nylon, polyester, and
most other engineering fibers are used.
These materials maintain a significant advantage over traditional
materials, such as those made from polyester or nylon, whose strength-to-weight
ratios are too low for advanced aerospace applications.

32. Cellulose Fiber Reinforced Nylon 6 or Nylon 66 Composites
Cellulose fiber was used to reinforce higher melting temperature engineering
thermoplastics, such as nylon 6 and nylon 66.
The continuous extrusion – direct compression molding processing and
extrusion-injection molding were chosen to make cellulose fiber/nylon 6 or
66 composites.
The continuous extrusion-compression molding processing can decrease the
thermal degradation of cellulose fiber, but fiber doesn’t disperse well with this
procedure.
Injection molding gave samples with better fiber dispersion and less void
content, and thus gave better mechanical properties than compression
molding.
Low temperature compounding was used to extrude cellulose fiber/nylon
composites.
Plasticizer and a ceramic powder were used to decrease the processing
temperature.
Low temperature extrusion gave better mechanical properties than high
temperature extrusion.

33. Nylon-6/Agricultural Filler Composites
According to plastic technology , Nylon-6 filled with
20 wt% of Curaua fibers were extruded and injection moulded
without addition of any additives.
Curaua give rise to modulus, strength and it is lighter than glass
fiber.
It has been claimed that Nylon-6 with 20 wt-% of this fiber has
been used in frame of the sun visor in the car.
The other fibers which were blended with Nylon-6 are sugarcane
bagasse .
It was found that melting point decreases by addition of fibers.
This is due to the partial miscibility of amorphous region of the
Bagasse fiber in Nylon-6 and the probability that the Bagasse fiber
changed the Nylon-6 crystalline size and structure or the presence of
strong interfacial interaction between fiber and matrix.

34. The rheological analysis of sugarcane bagasse
fiber/Nylon-6 composites showed an increase in viscosity with
an increase in the fiber loading and length.
In order to obtain composites with better mechanical
properties several modifications were done

35. Interphase of nylon 66 composits
The mechanical properties of glass fiber and carbon fiber
reinforced nylon 66 were investigated using both microscopic and
macroscopic testing techniques.
The objective was to determine how different interphase
morphologies affect the adhesion and properties such as damping,
ultimate stress and strain, and modulus of the composite.
The specific interphase that forms in both glass
reinforced and high modulus carbon fiber reinforced nylon 66 is
termed transcrystallinity.
Additional techniques such as scanning electron
microscopy, profilometry, thermogravimetric analysis,
differential scanning calorimetry, and water absorption
measurements were performed to assist in data interpretation.

36. CONDUCTIVE NYLON 6 NANOFIBER FOR MEDICAL
APPLICATION
Conductive Nano fiber use in make of nerve
matrix and help us for persuasion nerve with weak electricity flow
to injured limb.
Due to the high flexibility and high elongation
nylon 6 and high strength nylon 6 in front of some chemicals such
as acid and weak base chosen for the initial substrate and matrix.
Different ways is for used carbon nanotubes in
the production of nylon 6 nanofibers .
In general, the methods employed in the production
of carbon nanotube nano-fibers, nylon 6 is as follows:
 Using carbon nano-tubes before spinning
 Using carbon nano-tubes in spinning
 Using carbon nano-tubes after spinning

37. CONTINUOUS FIBER REINFORCED NYLON
COMPOSITES FOR STRUCTURAL APPLICATIONS
For applications that require a greater measure of
structural strength, nylons (polyamides) are commonly employed.
Many of these applications are satisfied with injection
molded nylon parts.
Advances in reinforced nylon materials have been
utilized to build front end bolsters, seat pans, bumper beams, battery
trays, gears, engine covers, and intake manifolds.
While development of LFRT (long fiber reinforced
thermoplastic) nylon technology has yielded improved properties and
allowed higher load profiles, the development of CFRT (continuous
fiber reinforced thermoplastic) nylon composites at Polystrand now
allow us to approach applications previously only possible with either
metal or thermoset composite construction.

38. "Nylon Composite Sheets"
The automotive industry is making increasing use of
hybrid technology (also known as plastic/metal composite
technology) for the volume production of highly integrated structural
parts that can withstand high stresses while still being light in weight.
Car roof frames are produced in polyamide using this
technique.
Nylon composite sheet can easily be formed and draped
after applying heat.
Because thermoplastic processing does not trigger a
chemical reaction, cycles are short and, most importantly, reproducible
results can be achieved with extremely low scrap rates.
Compared with metal, the investment needed to create a
preform is much lower, as only one tool is needed.

39. HNT in nylon
5%
10%
15%
30%

40. Excellent dispersion is observed up to 30% HNT levels.
DMA results show mechanical property
improvements and a HDT increase.
2% HNT exhibits major advantages over 17% GF
Lower weight
Substantial improvement in durability in flexural fatigue
test - no whitening
Improved impact resistance
Smooth surface finish