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HEAT
CURED POLYURETHANE CAST ELASTOMER SYSTEMS
Specifications
►
DESCRIPTION:
Ezecast casting systems are
two component systems which can, be used to produce high quality
Polyurethane elastomers with shore hardness ranging from 30A to 98A These
systems can be processed manually or by two component casting machines.
Large and complex parts can be cast without any difficulties using Ezecast
systems.
►
SALIENT
FEATURES:
-
HIGH
ABRASION RESISTANCE:
Ezecast
products are able to withstand a great deal of mechanical wear and tear.
This ensures a longer life of the products.
-
EXCELLENT
OIL RESISTANCE:
Ezecast
products are practically unaffected by oils and lubricants.
-
HIGH
ELASTICITY:
Products
made from Ezecast systems show high elasticity at all hardness levels.
-
WIDE
HARDNESS RANGE:
Ezecast systems can be used to
produce products of practically any hardness.
-
EXCELLENT
FLEXIBILITY:
Products
made using Ezecast systems are very flexible over a wide range of
temperatures.
-
GOOD
DAMPING PROPERTIES:
Ezecast
products have relatively high, mechanical loss factors and are therefore
suitable for
applications
where damping of high frequency vibrations is required.
-
GOOD
THERMAL RESISTANCE:
Ezecast
materials can be used at temperatures ranging from -40°C
to 90°C.
-
HIGH
RESISTANCE
TO
HYDROLYSIS:
Due
to their superb hydrolysis properties Ezecast products can be used in
highly humid conditions without any problems.
-
EXCELLENT
MACHINING PROPERTIES:
Above
80 ShoreA hardness Ezecast products can be machined easily, thus giving
the user, the flexibility to produce any
type
of machine finished component. .
-
HIGH
CHEMICAL RESISTANCE:
Ezecast
has good resistance to mild acids and alkalies and is unaffected by most
corrosive environments.
►
CASTING
PROCEDURE:
Ezecast
systems consists of two components which are mixed together, poured into a
mould and allowed to set to form a cast elastomeric polyurethane product.
Vacuuming and heating of the materials is required to ensure tough and
bubble free castings. The two components are selected from the 100 series
(i.e. Ezecast 101, 102,103…etc) and the 200 series (Ezecast.201, 202,203
….etc) depending on the hardness and properties of the cast product.
(Refer Table 1). If more than one component from the 200 series is to be
used, then these components should be premixed in the specified ratio and
used as a single component.
►
MOULDS:
Moulds made from steel,
aluminium or any other thermally and dimensionally stable material may be
used. While designing the moulds, shrinkage up-to 1% should be considered.
Exact shrinkage should be determined experimentally. Moulds should be
preheated to about 75°C-85°C
and a thin, even, layer of release
agent (paraffin‑wax or silicon) should be applied. by means of a
sponge or spray gun.
►
BONDING
AGENT:
For metal.
inserts, a bonding agent is required to ensure good adhesion between the
metal and the cast polyurethane Ezecast 110 and Ezecast 210 are mixed
thoroughly in the ratio of 1:4 by weight. This, mixture is applied to the
metal surface (preferably sand blasted to a clean, dry, rust-free
surface) by brush or spray and kept in the oven at 70°C
for 5 minutes. Pour the Ezecast casting mixture immediately and cure as
per usual procedure.
►
MANUAL
PROCESSING:
All the products in the 100
and 200 series are liquids except Ezecast 205 which is a solid. The
procedure of casting will change depending on whether a solid component is
being used or a liquid component.
►
PROCEDURE
WHEN USING LIQUID 200 SERIES COMPONENTS:
1)
All the 200 series components should be thoroughly stirred in their
containers (preferably at 60°C-70C). before use. It is very important to scrape the bottom of the
container during stirring to ensure that any material which has settled
down is properly mixed.
2) Take the 200 series
component (or combination of components) in a. container. The quantity
should be slightly more than that required as per the mixing ratio (Table
1). Add 2gm of Ezecast 204 (for obtaining better physical properties) for
every kilogram of the 200 series components taken and stir thoroughly.
Heat both the 100 and 200 series components separately up-to 70°C and vacuum the materials at an absolute pressure
less than 10 mm Hg for about 10 to 15 minutes. Keep the materials back in
an oven and maintain the temperature at 55°C-65°C).
3)
Stir the 100 series steadily while adding the exact quantity of the 200
series component to it (mix temperature-55°C
to 65°C).
Mix thoroughly, scrapping the sides and bottom of the container. Time
taken for this should be less than 2 minutes.
4)
Degas/vacuum the mixture immediately for about 2 minutes to remove air
bubbles which are trapped during mixing.
5)
Pour the degassed material into the preheated mould( 70°C-80°C ). To minimize air bubbles
entrapment, pouring is done along one of the walls of the mould.
6)
Place the mould in an oven at 100°C-110°C
for 2 to 3 hours and demouId. The exact time required to demould depends
upon the mould geometry and may vary from casting to casting.
7)
The demoulded part is
immediately put back into the oven (without allowing it to cool down much)
and cured for 16-24 hours to achieve full physical proper ties.
►
PROCEDURE
WHEN USING SOLID EZECAST 205:
1)
Take a known weight of the 100
series component in a container and heat it to 70°C., Vacuum this material at an absolute pressure
less than 10 mm Hg for 10 to 15 minutes and keep it in an oven to maintain
its temperature at 60°C
‑ 65°C.
2)
Take the solid Ezecast 205 (slightly more than the quantity required as
per the mixing ratio) in another container and heat it to 100°C to melt it. Care should be
taken to use up the Ezecast 205 immediately and in no case should its
temperature be allowed to exceed 110°C.
3) Stir the 100 series
component (at 60°C-65°C)
steadily while slowly adding Ezecast 205 (at 100°C). Mix thoroughly. If the 100 series component is
not stirred while adding Ezecast 205 then some of the Ezecast 205 may
precipitate as crystals.
4)
Degas the mixture immediately for about 2 minutes to remove air bubbles
which are trapped during mixing.
5)
Pour the degassed material into the preheated mould (80°C-90°C). Pouring is done along one
of the walls of the mould to minimize air entrapment.
6)
Place the mould in an oven at 110°C-120°C
for 1.5 to 2 hours and demould. The exact time required to demould depends
on the mould geometry and may vary from casting to casting
to 3 hours and demould. The exact time
7) The demoulded part is immediately put back into the oven (without
allowing it to cool down much) and cured for 18-20 hours to
achieve full physical properties.
►
MACHINE
PROCESSING:
Ezecast can be processed by a
two component, low pressure elastomer casting machine. In this case, the
degassed materials can be heated upto higher temperatures around 80°C.
The mixing ratio is adjusted on the machine and the mixed bubble free
material is directly poured into the preheated moulds.
►
MIXING
RATIOS:
TABLE 1:
●
Heavy
Duty PTMEG Based System: Applications requiring high abrasion resistance,
tensile strength, resilience, hydrolysis resistance and shock absorbing
properties
|
Sr
No.
|
Shore
Hardness
|
Ezecast
Comp.
A
|
Ezecast
Comp. B
|
Temp.
A
|
Temp.B
|
Mixing
Ratio A:B
|
Pot
Life
|
|
1.
|
94° A
|
106
|
205
|
65°
C
|
100°
C
|
100:16.3
|
7
Min
|
|
2.
|
90°
A
|
105
|
205
|
65°
C
|
100°
C
|
100:12.5
|
8
Min
|
|
3.
|
85°
A
|
105
+107
|
205
|
65°
C
|
100°
C
|
(50+50):10.6
|
10
Min
|
|
4.
|
80° A
|
107
|
205
|
65°C
|
100°C
|
100:8.6
|
10
Min
|
|
5.
|
75°
A
|
105
|
205+207
|
65°
C
|
100
C
|
100:(9.3+11.3)
|
12
Min
|
|
6.
|
70°
A
|
105
|
205+207
|
65°C
|
100
C
|
100:(6.5
+20)
|
12
Min
|
|
7.
|
65°
A
|
105
|
207
|
65°C
|
100
C
|
100:45
|
12
Min
|
●
Heavy
Duty Polyether Based System: Applications requiring high hydrolysis
resistance, good abrasion resistance, flexibility and low heat build up.
|
Sr.
No.
|
Shore
Hardness
|
Ezecast
Comp.A
|
Ezecast
Comp.B
|
Temp
A
|
Temp
B
|
Mixing
Ratio A:B
|
Pot
Life
|
|
1.
|
96°
A
|
101
|
205
|
60°C
|
100°
C
|
100:20.5
|
5
Min
|
|
2.
|
95°
A
|
101
+104
|
205
|
60°
C
|
100°
C
|
(95+5):20
|
6
Min
|
|
3.
|
90°
A
|
101
+104
|
205
|
60
C
|
100
C
|
(69+31):17.2
|
6
Min
|
|
4.
|
85°
A
|
101
+104
|
205
|
60
C
|
100
C
|
(34+66):13.5
|
7
Min
|
|
5.
|
80°
A
|
101
+104
|
205
|
65
C
|
100
C
|
(9+91)
:10.8
|
8
Min
|
●
Medium
Duty Polyether Based Systems: Non-dynamic applications requiring good
hydrolysis resistance, flexibility and elongation properties.
|
Sr
No.
|
Shore
Hardness
|
Ezecast
Comp.A
|
Ezecast
Comp.B
|
Temp
A
|
Temp
B
|
Mixing
Ratio A:B
|
Pot
Life
|
|
1.
|
95°
A
|
103
|
201
|
65°
C
|
65°
C
|
100:73
|
5
Min
|
|
2.
|
90°
A
|
102
|
201
|
65°
C
|
65°
C
|
100:64
|
6
Min
|
|
3.
|
85°
A
|
101
|
201
|
65°
C
|
65°
C
|
100:55
|
8
Min
|
|
4.
|
80°
A
|
101
|
201+202
|
60°
C
|
60°
C
|
100:(50+10)
|
10
Min
|
●
Light
Duty Polyether Based System: Application requiring high degree of
flexibility, hydrolysis resistance and low hardness.
|
Sr
No.
|
Shore
Hardness
|
Ezecast
Comp A
|
Ezecast
Comp B
|
Temp
A
|
Temp
B
|
Mixing
Ratio A:B
|
Pot
Life
|
|
1.
|
70° A
|
101
|
201+202
|
60°C
|
60°C
|
100:(42+20)
|
12
Min
|
|
2.
|
60°
A
|
101
|
201+202
|
60°
C
|
60°
C
|
100:(28.6+36.4)
|
12
Min
|
|
3
|
50°
A
|
101
|
201+202
|
60°
C
|
60°
C
|
100:(26+39)
|
15
Min
|
|
4.
|
45°
A
|
101
|
201+202
|
60°
C
|
60°
C
|
100:(24+41)
|
15
Min
|
|
5.
|
40°
A
|
101
|
201
+202
|
60°
C
|
60°
C
|
100:(22+44)
|
15
Min
|
|
6.
|
35°
A
|
101
|
201+202
|
60°
C
|
60°
C
|
100:(16+53)
|
15
Min
|
●
Heavy
Duty Polyester Based Systems: Applications requiring excellent solvent and
oil resistance, high tensile strength, abrasion and tear resistance
together with low rebound resilience and hydrolysis resistance.
|
Sr
No.
|
Shore
Hardness
|
Ezecast
Comp A
|
Ezecast
Comp B
|
Temp
A
|
Temp
B
|
Mixing
Ratio A:B
|
Pot
Life
|
|
1.
|
80° A
|
115
|
205
|
80°C
|
100°
C
|
100:9.2
|
10
Min
|
|
2.
|
70° A
|
115
|
205+208
|
80°C
|
100°C
|
100:(7.4+15)
|
10
Min
|
|
3.
|
65°
A
|
115
|
205+208
|
80°
C
|
100°
C
|
100:(6.4+22.5)
|
11
Min
|
|
4
|
60°
A
|
115
|
205+208
|
80°
C
|
100°
C
|
100:
(5.5+30)
|
12
Min
|
|
5.
|
50°
A
|
115
|
205+208
|
80°
C
|
100°
C
|
100:
(3.7+45)
|
12
Min
|
|
6.
|
40°
A
|
115
|
205
+208
|
80°
C
|
100°
C
|
100:
(1.9+60)
|
12
Min
|
|
7.
|
30°
A
|
115
|
208
|
80°
C
|
100°
C
|
100:75
|
15
Min
|
►
SAFETY
PRECAUTIONS:
1.
Handling of both Ezecast components should be done by persons wearing,
safety goggles, long rubber or PVC gloves and overalls fastened at the
neck and wrist.
2.
Splashes of both these products. in the eyes must be removed immediately
by careful and thorough rising with plenty of water. Medical assistance
must then be obtained.
3. Splashes
that come in contact with the skin must be removed immediately by thorough
washing with soap and water.
4.
Since both the products are processed at elevated temperatures special
care is necessary during heating of the material, when removing quantities
from containers, when mixing and then casting into moulds. Such work
should only be carried out in well ventilated rooms with efficient exhaust
ventilation at each individual work station. The flow air should be
directed away from the person handling the product and should move at a
rate at-least 0.5 m/sec. in the processing area.
5.
Vapours of these products will irritate the eyes. and the mucous membranes
of the nose, throat and lungs. Inhalation is therefore to be avoided under
all circumstances.
All
Ezecast formulations are subject to strict quality control, innovations
and improvements. The
above information is given on the basis of our best knowledge and
information and is for your guidance only. Specifications, however, are
subject to change and no guarantee is given or implied.
All
Rights Reserved. 1980 - 2015
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™