Aging and Degradation Phenomena Induced by Marine Environment on Plastic



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Aging and Degradation Phenomena Induced by Marine Environment on Plastic

A bioplastic can be biodegradable if it derives from organic materials such as wheat, corn or beet. A bioplastic can be biodegradable and made up entirely or in part of renewable plant raw materials annually. The bioplastics currently on the market are mainly composed of flour or starch from corn, wheat or other grains.

Specific types of bioplastic can be used in agriculture for mulching in the form of biofilm and solve the problem of disposal, as the film is left to decompose naturally on the ground. The land needed to grow the raw material for the bio-based plastics currently produced around the world amounts to approximately 0.02% of the arable land.

If, on the other hand, we based all current world production of fossil plastics on biomass as a raw material, the percentage would rise to 5%. The study: An In Situ Experiment to Evaluate the Aging and Degradation Phenomena Induced by Marine Environment Conditions on Commercial Plastic Granules, published on the Polymers, explained: "In this paper, we present two novel experimental setups specifically designed to perform in situ long- term monitoring of the aging behavior of commercial plastic granules (HDPE, PP, PLA and PBAT).

The results of the first six months of a three year monitoring campaign are presented. The two experimental setups consist of: (i) special cages positioned close to the sea floor at a depth of about 10 m, and (ii) a box containing sand exposed to atmospheric agents to simulate the surface of a beach.

Starting from March 2020, plastic granules were put into the cages and plunged in seawater and in a sandboxe. Chemical spectroscopic and thermal analyzes (GPC, SEM, FTIR-ATR, DSC, TGA) were performed on the granules before and after exposure to natural elements for six months, in order to identify the phy sical-chemical modifications occurring in marine environmental conditions (both in seawater and in sandy coastal conditions).

Changes in color, surface morphology, chemical composition, thermal properties, molecular weight and polydispersity, showed the different influences of the environmental conditions. Photooxidative reaction pathways were prevalent in the sandbox.

Abrasive phenomena acted specially in the sea environment. PLA and PBAT did not show significant degradation after six months, making the possible reduction of marine pollution due to this process negligible."