NCHRP IDEA 20-30/IDEA 204 [Active (IDEA)]
Biomimetic Antifreeze Polymers: A Novel Biodegradable Deicing Salt Alternative
| Project Data
||Univeristy of Colorado at Boulder|
||Wil V. Srubar III|
This project will synthesize and evaluate a class of low-cost, non-toxic, biodegradable antifreeze biopolymers with behavior similar to natural antifreeze proteins found in fish, plants, insects, etc. for their effectiveness in preventing ice formation on roadway and bridge surfaces during winter. Work on Stage 1 will focus on the synthesis and characterization of biomimetic antifreeze polymers (BAPs). Large-molecule Poly (lactic acid) (PLA) BAP, Poly (glycolic acid) (PGA) BAP and Poly (lactic-co-glycolic acid) (PLGA) BAP will be synthesized or synthetically modified to mimic ice-binding residues and their thermal hysteresis (TH) and ice recrystallization inhibition (IRI) activity will be investigated. PLA BAP molecules will be tested for purity, structure, and size. TH activity and ice crystallite morphology will also be characterized. Concentration-dependent TH and IRI curves will be generated. BAP activity will be tested in (i) deionized water, (ii) tap water, and (iii) relevant salt solutions. Work in Stage 2 will focus on the biodegradability and cytotoxicity of BAPs. The viability of living cells in the presence of PLA, PGA, and PLGA BAPs compared with traditional deicing solutions (such as NaCl, CaCl2, MgCl2, ethylene glycol) will be fully investigated. Molecules will be tested in ambient temperatures (for general cytotoxicity) and freezing temperatures (ice formation cytotoxicity). Biocompatibility of BAPs will be assessed compared to traditional freezing preservation methods using a LIVE/DEAD assay. Traditional freezing point depression solutions to be studied and compared will be NaCl, CaCl2, MgCl2, and ethylene glycol in solution. The long-term stability of PLA, PGA, and PLGA BAPs in aqueous and saline solutions will also be investigated. Molecules will be exposed to temporal and thermal stressors to replicate potential storage conditions. After the storage period, changes in BAP structure and performance will be tested in (i) deionized water, (ii) tap water, and (iii) relevant salt solutions. The biodegradability of PLA, PGA, and PLGA BAPs in aqueous and saline solutions will be assessed. BAP characteristics will be tested and normalized to find percent reduction of polymer integrity with respect to time. The final report will detail all relevant data/information and provide guidelines/recommendations on the use of the deicing biopolymers.