Investigation of the biodegradation of low-density polyethylene-starch Bi-polymer blends

Starch is one of the most widely available and easily obtainable natural polymers. This makes it an appealing bio-based alternative to synthetic polymers. Yet, the strong intramolecular and inter-molecular hydrogen bonds of starch polymer chains are a major obstacle in its plasticisation. This study showed that starch could be blended with polyethylene to form a partially degradable polymer. The processing conditions and sample formulations were shown to significantly affect the structure of the produced polymers which in turn influenced the degradation properties. Eighteen samples in all were produced by varying the composition of the blends between low-density polyethylene and each of Manihot esculenta, Zea mays, or Ipomoea batatas starches. Glycerol and water were employed as plasticizers in this study to reduce friction between polymer chains, improve flexibility, and provide optimal properties. More significantly, results have shown that the produced plastics are environmentally compatible, bio-degradable, compostable, and recyclable. This study has demonstrated the biodegradability of various starch-based polymers in the Sandy-Loamy soil.