Life Cycle Assessment of the Polyvinylidene Fluoride Polymer with Applications in Various Emerging Technologies

Abstract

Polyvinylidene fluoride (PVDF) is one of the most popular fluoropolymers in the market. It is commonly used as pipes and cables, binder materials, and membrane materials. Lately, PVDF is being examined for applications in batteries, biomedical research, chemical engineering, and wastewater management. These PVDF applications cover most emerging technologies, which can be attributed to its outstanding physicochemical properties. With the global demand for PVDF in diverse technologies increasing significantly, it is imperative to quantify the environmental impacts associated with its production. Life cycle assessment (LCA) methodology is a standardized approach for evaluating the environmental impacts of novel materials. However, most previous LCA studies have not accounted for PVDF in a scientifically rigorous manner. While compiling the life cycle inventory (LCI) on PVDF, several kinds of surrogates were chosen to bridge the data gap, rather than establishing the new dataset for PVDF. When we investigate the similarities and differences between PVDF and popular surrogates regarding the synthesis pathways, adopting surrogates to replace PVDF becomes difficult. Due to the use of these surrogates, the global warming potential (GWP) calculated in the literature varies significantly, with a difference of 60.7 kg CO2 equiv between the highest and lowest estimates. After evaluating the life cycle environmental profiles of those commonly used surrogates, we find that the application of surrogates is hardly reliable; besides, the PVDF inventory dataset is underestimated. For this reason, we model the PVDF production process according to the commercialized synthesis approach and assess the cradle-to-gate impacts, which lowers uncertainty. The impact assessment on the PVDF inventory dataset results in an acceptable GWP value (55.8 kg CO2 equiv/kg PVDF), but a high cumulative energy demand (CED, 756 MJ equiv/kg PVDF), due to the large demand for chlorine during the production of vinylidene fluoride (VDF). In terms of uncertainty analysis, the upper and lower bounds for the newly developed LCI dataset for PVDF are 801 and 714 MJ equiv for CED values and 59.1 and 52.8 kg CO2 equiv for GWP values, respectively. Notably, this is the first study to develop a detailed LCI for PVDF involved in emerging technologies.