Jute-carbon and glass-carbon hybrid composites of mixed matrix material [epoxy resin of bisphenol-C (EBC) and bisphenol-C-formaldehyde (BCF) of 50 wt% of the fibers] have been prepared by hand lay-up technique at 1508C under 7.6 MPa pressure for 2 h. Alkali-treated jute fibers have been acrylated to improve their physico-chemical properties. Tensile strength, flexural strength, electric strength, and volume resistivity of untreated (JCEBCF-50), treated (TJCEBCF-50) jute-carbon and glass-carbon (GCEBCF-50) composites are 10 MPa, 17 MPa, 1.60 kV/mm, and 5.9 Â 10 12 -cm; 14.65 MPa, 19.33 MPa, 2.09 kV/mm, and 6.79 Â 10 12 -cm; and 21.4 MPa, 24.53 MPa, 1.62 kV/mm, and 5.71 Â 10 12 -cm, respectively. Alkali treatment and acrylation of jute fibers resulted in 46.50, 13.71, 24.40, and 15.15% improvement in tensile, flexural, electric strengths and volume resistivity, respectively. Water uptake tendency of jute-carbon composite is considerably reduced upon alkali treatment and acrylation of jute fiber. Observed equilibrium water content in all the three composites is HCl 4 H 2 O 4 NaCl. Observed reduction in water uptake in TJCEBCF-50 is due to esterification of hydrophilic OH groups. In boiling water saturation time is reduced 20 times for JCEBCF-50 and TJCEBCF-50, and 16 times for GCEBCF-50 without any damage. Hybrid composites may be useful for low load bearing application and also in marine field.

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Jute—carbon hybrid composites (JCEBCF-10 to JCEBCF-50) of mixed matrix materials (epoxy resin of bisphenol-C (EBC) and bisphenol-C-formaldehyde (BCF) of 10—50 wt% of epoxy resin) have been prepared by hand lay-up technique at 150°C under 7.6 MPa pressure for 2 h. JCEBCF-10 to JCEBCF-50 possess 5.13—10.0 MPa tensile strength, 5.06—17.0 MPa flexural strength, 1.82—1.60 kV/mm electric strength and 3.16—5.90 × 1012 ohm cm, resistivity. Tensile strength and flexural strength have increased, while electric strength has decreased with increasing amounts of BCF content in the composites. Volume resistivity has decreased up to 30 wt% BCF and then it is increased. Water absorption by composites was carried out in water, 10% aq. NaCl and 10% aq. HCl solutions at room temperature and in boiling water. Observed equilibrium water content in JCEBCF-10 to JCEBCF-50 in water, 10% aq. NaCl, 10% aq. HCl and in boiling water is 8.00—5.87, 5.77—4.10, 10.00—7.40, and 7.1—5.5%, respectively. Observed diffusivity order is NaCl > H2O > HCl. In boiling water equilibrium water absorption time (6 h) is decreased 24 times as compared to room temperature (144 h) without any damage indicating excellent hydrolytic stability in boiling water and even in harsh acidic and saline environments.

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