Jute/Polyester Composites - Natural Polymers, Biopolymers, Biomaterials, and Their Composites, Blends, and IPNs - page 121

Jute fabric when used with general purpose polyester resin and large percentage
of cheap filler like calcium carbonate can find many low cost applications. Some of
the applications are grain storage silos, fishing trawlers and temporary/transportable
shelters. For protection against environment and water one outer layer of glass fabric/
polyester can be used. Also, jute with thermoplastics matrices finds many applications
in automotives, rail coaches, etc.
eXPerimeNtal
materials
Two types of commercially available jute fabrics were used: Hessian cloth with starch
and Hessian cloth without starch. Isophthalic polyester resin was used as matrix.
Methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate were used as catalyst
and accelerator, respectively. Calcium carbonate (200 mesh) was used as filler.
Fabric treatment
The above two fabrics were given two types of treatments:
Alkali treatment : Jute fabrics were soaked in 2% (w/w) NaOH solution for 2 hr.
Then, they were washed thoroughly with distilled water and dried at 60°C for 24 hr
in hot air oven.
Thermal treatment : Jute fabrics were dried at 100°C for 2 hr in hot air oven.
Nomenclature for composite specimens is as given below:
Hessian starch untreated/polyester-HSUNTR
Hessian starch alkali treated/polyester-HSAL
Hessian starch alkali treated with mechanical constraint/polyester-HSALMC
Hessian starch thermal treated/polyester-HSTHER
Hessian untreated/polyester-HUNTR
Hessian untreated/polyester-HAL
Polyester-POLYESTER
Processing
Hand lay-up (contact molding) method was used for preparation of jute/polyester
composite laminates. 1.5% catalyst (MEKP) and 1.5% accelerator (cobalt naphthe-
nate) was used for room temperature cure of isophthalic polyester resin. Filler (cal-
cium carbonate) was added up to 40% by weight of resin. Fiber content in composite
was maintained at around 30%.
mechanical testing
Mechanical properties were evaluated using an INSTRON universal testing machine
(Model 4301). Tensile, flexural and interlaminar shear properties were determined
according to relevant ASTM standards. Izod impact strength was determined using
impact tester (Zwick, Germany).