Cardboard formulation made from banana stalks and coconut coir using linear programming method

Malang Regency produced 690,136 tons banana in 2016. The production is line with the waste (banana stalks). Banana stalks contain 83.3% cellulose and 2.97% lignin, of which can be used as raw material for paperboard making. However, leaf paper has a low tensile strength 7.45 N/mm2, so additional fibers to strengthen necessary, such coconut coir 46.67 N/mm2. This research aimed formulate making, fiber source fronds coir), filler (tapioca), water produce minimal costs. was conducted using linear programming method LINDO software. formulation sheet cardboard 34.79 g dry stalks, 19.20 coir, 6.00 tapioca, 136.08 NaOH, 2080 mL distilled water, 1000 manufacturing cost IDR 6,931.15. characteristics gramature 323.8 g/m2, moisture content 19.75%, absorption test 743.2 resistance 1.4 kN/m, stiffness 5.7 mN.m.