Caracterización de las propiedades mecánicas, estructurales y térmicas de biocompuesto plástico a base de almidón de yuca y fibra de cabuya, procesado mediante moldeo por compresión

Abstract

The aim of the present work was to characterise the mechanical, structural, and thermal properties of cassava starch polymers reinforced with cabuya fibre, processed by thermocompression moulding. The fibres were surface treated in a solution of 0.1% KMnO_4 and 5% oxalic acid C_2 H_2 O_4. The heat engine was developed from a resistor, a thermocouple, and a steel plate, with dimensions of 50x50x9mm^3. Five different samples of polymer composite were moulded at a temperature of 145^o C for 40min, varying their pressure, TPS, amount of water and arrangement of fibres, all with the aim of investigating the variables that result in higher efficiency. Sample 1 is chemically different from the rest, due to its formulation with different percentages of starch, glycerine, and water. Samples 2 and 5 have an ABC sandwich fibre arrangement, while samples 1, 3 and 4 have an AB arrangement. It was obtained that, the amount of chemical concentration intervenes in the morphological, mechanical, and thermal behaviour, therefore, sample 1 had the lowest modulus of elasticity, with no pores on its surface, proving to have more resistance to heat. Samples 2 and 5 had the best fibre- matrix adhesion due to their fibre arrangement. With the pressure variations in samples 3, 4 and 5, it can be said that the higher the pressure, the higher the modulus of elasticity. In conclusion, each sample was mechanically, structurally, and thermally characterised, finding that sample 5 was the most efficient; its modulus of elasticity ranges from 494 to 539MPa, it has high porosity, and thermal degradation temperature from 〖200 a 585〗^o C. All samples proved to be superficially rough with low polymer-fibre adhesion, to improve this, the fibres should be cut much smaller and mixed with the polymer at constant speed.