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PRODUCT TRADE NAME : ABRON R 750
PRODUCT TYPE : POLYIMIDE RESIN (Bis-itaconimide type) Powder Resin |
As a result of the efforts of Indian Space Research Organization to develop a processible polyimide, a prepolymer having excellent processability, stability at room temperature and with moderate cure temperatures was developed. Composites made from this prepolymer have yielded components for space and aerospace applications. ABRON-R 750 is being manufactured by A B R ORGANICS LIMITED with the license from Indian Space Research Organization.
ABRON-R 750 is highly amenable for polar & filament winding technology also. The prepregs made from ABRON-R 750 have a long shelf life of 3 to 6 months at room temperature. |
| GENERAL PROCEDURE FOR MAKING LAMINATES |
| Silica/Glass/Carbon cloth is impregnated with the resin solution. The solvent is allowed to evaporate (at 55 - 60°C when DMF is used as an solvent). The prepreg should have resin content of 35 - 40% weight. |
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The tack & drape of the prepreg is controlled by adjusting the residual solvent content. The prepregs are stacked in mold and heated to 120°C and held for one hour under 60 psi pressure. The mold temperature is raised to 160 - 165 °C as a second step and maintained for another hour. Final cure is done by heating the mold to 200 - 220 °C for 2 hours under pressure. The laminate is released after cooling under pressure to 80 - 100 °C. Post curing is to be done at about 125 °C for 6 hours. |
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| This procedure, however is not same for all shapes and thickness of laminates. The exact cycle has to be determined based on trials. |
APPLICATIONS
- Aerospace & space applications as resin matrix for composites ·
- Slot wedges for locomotive traction motors
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| SPECIFICATIONS OF ABRON-R 750 |
| State |
Fine Powder |
| Colour |
Light Pinkish Brown |
| Specific Gravity at 25°C |
1.1 |
| Solubility |
NMP / DMF |
| Bulk viscosity of 40% Solution |
40 - 100 cP |
| Shelf life of Resin Powder |
6 months at ambient temperatures (< 400 C ) |
| Service Temperature |
-200 to +300°C |
| Cure Temperature |
200 °C - 230 °C |
| Dielectric Constant |
80 - 90 KV/mm |
| Surface Resistivity at 25 °C |
0.5 X 1014 Ohm.cm |
| Volume Resistivity at 25 °C |
2.9 X 1014 Ohm.cm |
| Tan d at 25 °C |
0.004 |
| Volume Resistivity at 200 °C |
4.7 X 1012 Ohm.cm |
| Tan d at 200 °C |
0.025 |
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MECHANICAL PROPERTIES OF LAMINATES (ASTMD - 1184)
CARBON FIBRE (UNIDIRECTIONAL) |
TENSILE STRENGTH |
8 X 103 kg/cm2 |
| FLEXURAL STRENGTH |
5.5 x 103 kg/cm2 |
| INTERLAMINAR SHEAR STRENGTH |
305 kg/cm2 |
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| GLASS FIBRE (UNIDIRECTIONAL) |
| TENSILE STRENGH |
5.2 X 103 kg/cm3 |
| FLEXURAL STRENGTH |
5.0 X 103 kg/cm3 |
| INTERLAMINAR SHEAR STRENGTH |
135 kg/cm2 |
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ELECTRICAL PROPERTIES OF GLASS-POLYIMIDE COMPOSITE :
- Dielectric Constant at 10 KHz frequency with 3.3 mm thick laminate = 2.1
- Descipation factor at 10 KHz frequency with 3.3 mm thick laminate = 0
- a) Electromagnetic radiation transparency with unidirectional glass/ PI laminate at 11.9 G.Hz ------- 89%
- b) Glass cloth - PI laminate ------- 52% c) Glass cloth-epoxy laminate ------- 5 6%
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| Tensile strength |
400 Mpa |
| Flexural strength |
450 Mpa |
| Inter Laminar Shear strength |
25 Mpa |
| Resin content |
26 to 28% only |
| Density |
1.8 - 1.9 gm/cc |
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The above properties meet the requirements of composites functioning upto 220°C and at 400 °C for short duration application.
MECHANICAL PROPERTIES OF LAMINATES BASED ON ABRON-R 750 |
| Composite systems |
Tensile strength 103
kg/cm2
Av S.D |
Flexural strength
103 kg/cm2
Av. S.D |
Interlaminar shear
Strength kg/cm2
Av. S.D |
ABRON R 750/carbonUnidirectional |
8.094 0.055 |
5.79 0.565 |
305.55 23.22 |
ABRON R 750/glassUnidirectional |
- - |
8.614 1.15 |
325.9 6.30 |
ABRON R 750/glass
Cloth |
- - |
3.62 0.11 |
250.9 5.8 |
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| MECHANICAL PROPERTIES OF THERMALLY AGED COMPOSITES |
Temperature0 C |
Flexural strength |
ILSS |
| |
ABRON R 750 |
ABRON R 750 |
| 30 |
2530 |
325 |
| 150 |
2741 |
- |
| 175 |
2806 |
- |
| 200 |
2840 (2261)* |
291.5 |
| 250 |
3022 |
300 |
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- Value obtained after soaking the sample for 100 hrs at 200°C.
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