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APPAREL VIEWS / NOVEMBER 201130
As per federal trade commission Melamine fibre is defined as, a manufactured
fibre in which the fibre-forming substance is a synthetic polymer composed
of at least 50 per cent by weight of a cross-linked Melamine polymer and it is mainly
produced by Basofil fibres LLC, Enka, NC and marketed under the trade name, Basofil
fibre. Basofil is an advanced technology Melamine fibre designed to enhance
commodity fibres and synergistic high-temperature fibres to deliver cost-effective,
engineered heat insulating and flame-resistant solutions and that the fibre, which is
white and dyeable, can be processed on standard textile manufacturing equipment
for the production of woven, knitted, and nonwoven fabrics.
Production of Melamine fibre
The production process Melamine fibre is proprietary. It is based on a unique
Melamine chemistry that results in a cross-linked, non-thermoplastic polymer of
Melamine units joined by methylene and dimethylene ether linkages. In the
polymerization reaction, methylol derivatives of Melamine react with each other
to form a three-dimensional structure. This network structure of Melamine fibre
produces unique fibres with excellent inherent characteristics for fire protection,
heat stability and low flammability – that is also durable and resistant to chemicals
and ultraviolet light. Further, Melamine’s most outstanding physical properties
are its high Limiting Oxygen Index (LOI), low thermal conductivity and the fact that
it does not shrink, melt or drip when exposed to a flame.
Fibre properties
Melamine fibre is a cost effective heat resistant fibre with a 400°F (200°C)
continuous operating temperature. Melamine fibres are flame resistant, have
outstanding heat/dimensional stability, and are self-extinguishing.
Below are some important characteristics of Melamine fibre:
• Inherent, non-toxic protection - Fabrics made with Melamine are proven to be
non-toxic and non-irritating through vigorous and extensive evaluation of VOC
off-gassing, smoke density and skin irritation
• Highly insulating - Melamine is the most thermally insulating fibre available,
boasting the industry’s highest Thermal Protective Performance (TPP) ratings
• Attractive finish - Melamine is white in colour and dyeable to support many
different fabric finishes
• Durable and protective - With a superior dimensional stability, Melamine will
not shrink, melt or drip, making it an excellent choice for protection in electric
arc, flash fire, molten metals and hot gas environments
• Cool and breathable - Elliptically-shaped Melamine fibres allow fabrics to
breathe better and keep wearers cooler
• Melamine retains its protective qualities and durability through repeated
launderings • Chars without shrinking • Low thermal conductivity
• High heat dimensional stability • Processable on standard textile equipment
• Unparalleled ultraviolet (UV) resistance • Melamine is insoluble
• Improve durability through fibre blending
• Optimised design includes:
• Minimising apparel weight and thickness
• Maximising durability and minimising lifecycle costs through fibre blending
Blending with other fibre
Melamine fibres can be blended with both synergistic high temperature fibres and
commodity fibres for peak performance.
• Melamine/cellulose • Melamine/polyester
• Melamine/aramid • Melamine/meta-aramid
Because of its variable denier and staple length, low tensile strength, and
difficulty in processing, Melamine is generally blended with stronger fibres
such as aramids. It is more often used in needled products or yarns made from
wrapped spinning techniques, though recent advances have led to satisfactory
ring spun yarns, blended with other fibres, such as para-aramids, suitable for
weaving into firemen’s turnout gear. This development may lead the way to its
adoption in other areas.
Faster, stronger, lighter, safer... these demands are constantly being pushed upon by today's researchers and manufacturers,
including protective clothing - routine or specialised. High performance and high temperature resistant fibres aid enormously
in allowing products to meet these challenges. The markets and products, which are facilitated by the use of these fibres, go
far beyond the scope and awareness of most people. Melamine fibre has recently entered the high temperature fibre
market, one of the newest fibres, and has made a rapid impact. Melamine fibre is an advanced synthetic fibre having
superior heat and flame resistance with decomposition temperature above 350°C
Self-extinguishing behaviour of model paper with 35 per cent WF series Melamine fibre.
APPAREL VIEWS / NOVEMBER 2011 31
Uses and applications
Apparel made with Melamine provides superior comfort, softness and
breathability while protecting people who work in hazardous environments.
Melamine is suitable for competitive and compliant protective apparel solutions
those are well-suited to industrial, military and fire service professions. In the
event of a fire, protective apparel must resist flame exposure and protect the
wearer. Fabrics made with Melamine retain flexibility and dimensional stability
when exposed to direct flame, ensuring that protective garments will not break
open or shrink away during fire exposure.
Fabrics made with Melamine add insulation and protection in technical apparel.
Following are the major application of Melamine fibre in apparel:
• Fire fighter turnout gear, including gloves and hoods
• Military and law-enforcement protective gear
• Industrial garments and protective workwear
• Racing apparel
Apart from apparel, Melamine is also used for below application in industry:
• Mattresses, home furnishings/nonwovens
• Speciality flame resistant papers
• Electrical papers
• Transmission/friction papers
Measurement Units Typical values
Colour Ivory white
Average diametre µm 15
Average denier g/9000m 2.2 - 2.4
Specific gravity g/cm3 1.4
Tensile strength ksi 36
Tenacity g/den 2.0
Modulus Msi
g/den 1.0 55
Elongation at break Per cent 11
Moisture regain Per cent 5(23°C, 65 per cent RH)
Shrinkage at 200°C Per cent <1(1 hr exposure)
Limiting oxygen index Per cent 32
Maximum continuous °C 200operating temperature
Maximum use temperature °C 260-370°C (500-698°F)
Melting temperature °C Does not melt or drip
Hot air shrinkage, 1 hr. @ 200°C Per cent <1
Resistance to mildew, aging, sunlight Excellent
Resistance to solvents, alkalis Excellent
UV resistance No strength lossafter 200 hrs. xenon
Important properties of Melamine fibre
Melamine – Fibre cross section, longitudinal view, fabric and yarn
Protective converalls made with a Basofil/aramid firber blend hold up to flash-fire conditions
Beginning of test Mid-test End of test
Heat Dimensional Stability
(A) Basofil (B) Para-aramid (C) Meta-aramid (D) Rayon (E) Polyester (F) Modacrylic
By Vasant R Kothari, Assistant Professor, NIFT, Bangalore
(Author can be contacted @ www.vasantkothari.com)
• Filtration media
• Engineered materials/Short-fibre composites
• Adhesives/Fillers
• Tire sealants
• Truck/Rail brakes
• Fire blocking fabrics: Aircraft seating, fire blockers
for upholstered furniture in high-risk occupancies
• Filter media: High capacity, high efficiency, high
temperature bag house air filters.
Conclusion
High performance fibres and high temperature resistant fibres offer numerous
advantages over traditional fibres. Higher strength, lighter weight, higher operating
temperatures and flame-retardant ability are some of the most prominent features
of these fibres. These outstanding properties create opportunities to manufacture
products that historically could not be made due to technical constraints. The
protective clothing area is one of those markets.
High performance fibres allow companies to enter niche markets, which typically
provide higher profits as well as strong barriers to entry for the competition. Even
in the high performance area, many markets have become "commodity"
applications, particularly them Melamine in protective clothing, specifically fire
resistance. The protective clothing market will continue to bring new opportunities
for high performance fibres as the fibre manufacturers expand their current product
lines as well as create new and exciting specialised materials.
Having only recently been introduced, Melamine has a limited range, but rapidly
growing, of on-going applications. Potential looks promising for this high
performance, low cost fibre to find its way into a number of existing areas, especially
as processing difficulties are overcome