https://digitalcommons.calpoly.edu/nres_rpt/13
Date of Award
9-2021
Degree Name
MS in Environmental Sciences and Management
Department
Natural Resources Management
College
College of Agriculture, Food, and Environmental Sciences
Advisor
Anastasia Telesetsky
Advisor Department
Natural Resources Management
Advisor College
College of Agriculture, Food, and Environmental Sciences
Abstract
The global production and mismanagement of plastic has led to plastics deposited and scatted across marine environments. Conventional plastic, which most Americans encounter every day, is produced from fossil fuels and lacks the ability to fully break down upon disposal, breaking down into microplastics that can remain in the natural environment for hundreds of years. Moving away from petroleum-based plastics could lead to a reduction in greenhouse gas emissions and decrease plastic particles in the ocean. Based on existing literature, there are three biopolymers that could serve as replacements to conventional plastics in the marketplace. These biopolymers are seen as viable replacements because of their fast biodegradation and low carbon footprint associated with production. These three biopolymers are Polylactic acid (PLA), Polybutylene succinate (PBS) and Polyhydroxyalkanoates (PHAs). This study describes the properties of each biopolymer, evaluates the existing research and studies conducted on each biopolymer, and provides analysis determining which biopolymer might be able to replace conventional plastics based on the criteria of carbon footprint, energy, and cost. When simulating the polymers for the production of a water bottle and comparing to conventional plastic PET (Polyethylene terephthalate),. PLA was the most likely biopolymer to replace PET because of a lower carbon footprint and lower energy usage during production. However, PLA is more expensive than PET and has poor biodegradation in the marine environment (15.86 years). PHB had a lower carbon footprint and lower energy usage than PET with an estimated biodegradation period of 1.19 years. However, PHB is more expensive than both PLA and PET. Because of these results, there needs to be more research focused around strengthening biopolymers’ mechanical structure, lowering costs of biopolymer production, and for PLA – improving biodegradation in the marine environment.