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Different kind of foams
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[Name]| TXL-752 | [Date]
Foam Types DIFFERENT KIND OF FOAMS AVAILABLE TILL DATE
PAGE 1
DIFFERENT TYPES OF FOAMS
CLOSED CELL FOAM
1. Ethafoam (Polyethylene) : Polyethylene foam, strong, resilient,
lightweight, flexible, solid extruded,
medium density (220-as)/high
density (600), closed-cell foam.
Uses: Shock absorbing, vibration damping,
insulation, impervious to most chemicals, Closed
foam, and as a material for cushioning components
in packaging applications for loading up to 17.5
kPa(220-as), 69kPa(600).
Formulated with anti-static properties to safely
protect sensitive electronic equipment during
shipment and storage, outstanding dimensional
stability and recovery characteristics that provide optimal cushioning protection against repeated impacts, it is
ideal for cushion packaging and is used in many computer and electronics application.
Physical properties Direction Value (220-as) Value(600)
Density 35.2 kg/m3 96.1 kg/m3
Static Decay Rate < 2 sec
Compression Set Vertical < 20% (50% compr.) < 15% (50% compr.)
Compressive Creep
(1000 hrs @ 23 c)
Vertical < 10% (17.5 kPa) < 10% (69 kPa)
Thermal Stability (ISO 2796)
< 2% < 2%
Thermal Conductivity
24 c / -5 c
Vertical .42 / .37 (W/m K) .42 / .37 (W/m K)
Water Absorption < 3% by volume < 1% by volume
Tensile Elongation Average 50% 55%
Tensile Strength @ Peak Average 220 kPa 552 kPa
Tear Strength Average 1.75 N/mm 5.3 N/mm
PAGE 2
Volara (Cross-linked Polyethylene foam):
Flexible closed-cell polyethylene foam
that is cross-linked by means of a unique
electron irradiation process. This results in a
continuous smooth surface foam with a fine cell
structure and excellent mechanical properties.
Good mechanical properties at low densities, low
water absorption and vapor transmission,
excellent thermal insulation, excellent chemical
resistance, smooth aesthetically pleasing surface.
USES: cap seals, medical tape, sports padding
Physical properties
Direction Value (2 pcf) Value (4 pcf) Value (6 pcf)
Density 1.8-2.2 pcf 3.6-4.4 pcf 5.4-6.6 pcf
Compression Set 28 18 14
Thermal Stability (ISO 2796)
M
CM
-2%
-1%
-1.5%
-0.7%
-1.0%
-0.7 %
Thermal Conductivity
21 c
.25 (W/m K) .30 (W/m K) .32 (W/m K)
Water Absorption (lbs/sq. ft. of cut surface)
.04 .04 .04
Elongation To Break M
CM
124 %
88 %
177 %
126 %
203 %
140 %
Tensile Strength @ Peak
Average 60 psi 123 psi 177 psi
Tear Resistance (lbs/inch)
M
CM
6
11
15
24
24
35
- = shrinkage M=machine direction, CM = Cross section machine direction
PAGE 3
Rebonded Flexible Foam (moulded polyurethane):
Bonded foam, or rebound, is a moulded polyurethane product made from pieces of shredded flexible polyurethane foam held together with a binder. It relative high density and excellent resilience make it suitable
for applications including vibration sound damping,flooring, sports mats, cushioning, packaging and carpet
underlay.
Density kg/m3 60 300
Tensile strength kPa 40 150
Elongation at break % 40 90
CLD hardness at 10 % compression
at 20 %
at 30%
4 20
5 50
15 - 150
Neoprene foam:
Due to the superb air tight and water tight properties of expanded Neoprene foam (also known as neoprene sponge) it is generally used within the automotive, electronic and construction trades.
Its properties also make it suitable for requirements including thermal insulation on items such as garage door
seals.
PAGE 4
Closed cell structure making it impermeable to air and water and therefore an ideal material for sealing against air and/or water.
Outstanding aging properties and will not go brittle over time.
Very durable and relatively cheap.
Flexible material.
Good UV, ozone, sunlight and oxidation resilience.
Flame retardant.
Good resistance to oil and many petroleum derivatives and chemicals.
Density: lb./ft3 (g/cm3) 6 + 2 (0.096 + 0.032) Hardness 45 + 5
Compression Deflection 25%psi (kPa) 3.5 + 1.5 (24 + 10)
Compression Set %
PAGE 5
Good UV resistance.
Good mechanical properties.
Wide temperature range.
Cellular Structure Closed Cell
Shore Hardness .02 g/cc
Compression Deflection (00 scale) 5-9 psi
Compression Set (50%) 25% max
Water Absorption 5% max
Linear Shrinkage 10 days / 23 C 3% max
Elongation at Break 90 % minimum
Tensile Strength 65 (min) lb/in
Max Use Temperature -40 to 100 C
Air & UV Resistance Good
Ozone Resistance Very Good
EVA Foam (Ethylene vinyl acetate):
Light weight, shock resistance and high elasticity, odorless, good mechanical strength, excellent chemical resistance, high buoyancy, low water absorption, good acoustic properties.
USES: athletic padding, thermal insulation, thermoformed protective covers, a variety of other uses which require good chemical or water resistance.
Physical
Properties Units 2 lb 4 lb
VS
Foam
9115
VS
Foam
9125
VS
Foam
9135
VS
Foam
9145
VS
Foam
5555
VS
Foam
5565
VS Foam
5575
Firm
6 lb
Firm
9 lb
Hardness Duro 'A' ---- --- 15-25 20-30 30-40 40-50 50-60 60-70 70-80 34-45 45-55
Density lb/ft3 1-3 3-5 5-7 8-10 11-13 13-15 14-17 16-19 19-23 5-7 8-10
PAGE 6
25%
Compression
Deflection
psi 3 5-10 10-15 20-30 30-40 50-60 -- -- -- 40 50
Compression
Set
% of
Original 15 10 10 10 10 10 7 7 7 25 20
Tensile
Strength psi 30 50 180 225 350 375 375 450 480 150 300
Ultimate
Elongation percent 150 150 250 300 300 350 175 200 150 50 50
Die C Tear lb/in 10 15 25 35 50 60 60 75 90 40 50
Water
Absorption lb/sq ft
PAGE 7
Tensile Strength Psi 25 minimum
Compression force 25% deflection Psi 1.5-3.0
Compression Set 50% 35 maximum
Temperature range F -40 to 220
Water Absorption 10% max
Thermal stability (% change in length, 7 days @ 220F)
10% max
Thermal conductivity BTU-IN .290 max
Ozone Resistance Pass
Silicone Sponge:
Made from gum based polydimethylsiloxane (PDMS).Expansion process creates the closed cell sponge structure, creating compressible air pockets.
Wide operating temperature - Silicone sponge has a temperature range of -100F to 500F (-73C to 260C).
Water sealing - the closed cell structure allows for good water sealing with relatively low compressive forces.
Compression set resistance - Silicone offers excellent compression set resistance (ability to rebound to original thickness), especially at higher temperatures, compared to most rubber material. Low compression set silicone sponges are available for even better performance than general purpose grades.
UV and ozone resistance - Silicone products have excellent UV and ozone resistance due in part to their inorganic backbone. This provides long term performance.
Rugged - When silicone is required, silicone sponge parts offer better toughness as compared to silicone foam products.
Outdoor gasketing - Considering all the above benefits, silicone sponge is a good material choice for outdoor environments, from the Arctic to the desert.
Flame retardant silicone sponge (R10400 M):
Property Unit Value
Density Lbs./ft3 (kg/m) 35 (560)
Compression Deflection Psi (kPa) 10 (69)
Elongation % 250
Tensile Strength Psi (kPa) 100 (690)
Compression Set % 10
Tear Strength ppi (kN/m) 20 (3.5)
Water Absorption % 1
Operating temperature F (C) -100 to 500 (-73 to 260)
PAGE 8
SILICONE SPONGE OR SILICONE FOAM? WHAT IS THE DIFFERENCE?
Silicone foam is manufactured from a low viscosity liquid silicone which is cast on a smooth liner and cured
through inline ovens. Silicone foam can be supplied as an open cell, closed cell or combination of both, open
and closed cell material.
Silicone sponge, on the other hand, is mixed and calendared on a rubber mill then cured via inline ovens or
stationary mold press.
Silicone foam is typically lighter in density, compresses with less force and has a lower compression set than
silicone sponge. Both products have good sealing properties, however the sponge has higher tensile strength
and the foam has better flame resistance.
Composite foam:
Honeycomb:
Polypropylene Honeycomb: Tough and durable, strong impact resistant, resistant to moisture, high
sound and vibration attenuation.
Aramid (Nomex) Honeycomb: Aramid fiber paper is an excellent lightweight non-metallic core material.
Nomex offers excellent resiliency, low density, corrosion
resistance, flame retardancy, and good compressive strength
to weight ratio.
Kevlar honeycomb: Better than Nomex,
particularly in compressive strength.
Carbon-fiber Honeycomb: Carbon fiber can also be used as a core material; however cost is high. Limited to space application, e.g. Satellites, where weight saving is critical and thermal expansion need to be
kept at a minimum.
Metal honeycomb: Various metal are used according to the application and property needed,
Aluminum is common metal. The compressive shear strength of aluminum honeycomb are excellent.
PAGE 9
Foams: Foam cores produce extremely lightweight composite structures. High density foam cores provide greater resistance to
compression and crush, as well as provide damage tolerance from
impact. Low density foam cores with carbon-fiber face sheets,
Airex foam core: Airex is a closed cell, cross-linked polymer foam, which is lightweight and has good impact strength.
Depron foam core: Depron is an inexpensive, non-structural foam. A Depron carbon fiber foam core laminate has excellent strength
and stiffness in bending; however, lacks the compressive strength and
crushing resistance of a structural foam core.
Divinycell foam core: Divinycell foam core is a medium density structural foam with very high strength, often used for heavier duty applications where lighter density foams may not work. In particular,
Divinycell H100 is an excellent damage tolerant foam, and is ideal for applications that require resistance to
impact and local crushing.
Wood
Balsa wood: Balsa wood, when used as a core material in composite fabrication, offers a very high strength and stiffness to weight ratio. End grain balsa
provides exceptionally high shear, tensile and compressive strengths for its weight.
Balsa is also a renewable resource, with typical balsa trees maturing to 90 feet in
seven years.
Birch plywood: Birch plywood is higher density than balsa wood, providing a durable final product
with excellent compressive strength, resistance to local crushing, and machinability.
OPEN CELLED FOAM
PAGE 10
Dry fast foam (polyurethane foam):
Dry fast foam is an outdoor foam which has open cell structure and is perfect for areas
where cushions get wet. Dries almost
immediately after exposure to: rain, salt spray,
melting snow, morning dew, washing, or other
type of moisture and humidity. Large, open pores
permit maximum water drainage and air
circulation, allowing use quickly after being wet
or even saturated. Dryfast foam formula is anti-
microbial and help suppress microorganism
growth, common in damp area.
USES: outdoor furniture, boat or marine
cushions, pool, filtering for whatever is exposed
to large amount of water.
50 ILD EZ-Dry Foam
Pore size 35 ppi
Density 2.0 lbs./ft3.
Tensile 8 psi
Elongation 25 %
Tear 2 lbs./in
Compression Set 50% 15 %
Properties:
Compression set max : Vinyl/nitrile>Volara>Neoprene>EPDM>Ethafoam>Dry foam>EVA>Silicone Sponge
Tensile Strength :EVA>Silicone sponge>Volara>Neoprene=Ethafoam>rebonded>EPDM>Vinyl/Nitrile>Dry
foam
PAGE 11