Modifikasi Asam Ampas Sagu dan Pengaruhnya Terhadap Sifat Fisik Mekanik Biofoam

Abstract

Styrofoam is one of packaging materials that are widely used, and produced from non-renewable resources. Natural polymeric materials such as starch and fiber can be used as an alternative raw material for biofoam production. Sago hampas contains large amounts of starch and fiber, but naturally starch and fiber has disadvantages because its moisture sensitivity and poor mechanical properties, so it needs to be modified to improve its properties. This study aimed to assess the effect of acid modification on the characteristics of sago hampas produced, utilization of acid modified sago hampas for biofoam production, and characterization of biofoam‘s physical mechanical properties. Acid modification is conducted by soaking the sago hampas in 0.144% of HCl solution in methanol for 0, 60, 120, 180 and 240 hours. Biofoam was produced from the mixture of sago hampas, sago starch, synthetic polymer (polyvinyl alcohol), and additives; and then molded by thermopressing method. The results showed that the longer soaking time proved to cause the damage of the starch. Compared to native sago hampas, acid soaking also caused a decreasing in crystallinity, even crystallinity pattern changed after 60 hours of soaking time. This affected to the characteristics of the biofoam produced. Washing the sago hampas without soaking (treatment 0 hours) resulted biofoam with better physical mechanical characteristics compared to native sago hampas, as decreasing in water absorption (57.13%); increasing the tensile strength (19.14 MPa), modulus of elasticity (358.21 MPa) and modulus of rupture (7.25 MPa). Compared to styrofoam, the biofoam which produced from modified sago hampas has better mechanical properties in modulus of rupture (1.61-7.25 MPa) and modulus of elasticity (104.62-358.21 MPa).