Self-Cleaning Photocatalytic Polyurethane Coatings Containing Modified C60 Fullerene Additives

Abstract

Surfaces are often coated with paint for improved aesthetics and protection; however, additional functionalities that impart continuous self-decontaminating and self-cleaning properties would be extremely advantageous. In this report, photochemical additives based on C 60 fullerene were incorporated into polyurethane coatings to investigate their coating compatibility and ability to impart chemical decontaminating capability to the coating surface. C 60 exhibits unique photophysical properties, including the capability to generate singlet oxygen upon exposure to visible light; however, C 60 fullerene exhibits poor solubility in solvents commonly employed in coating applications. A modified C 60 containing a hydrophilic moiety was synthesized to improve polyurethane compatibility and facilitate segregation to the polymer-air interface. Bulk properties of the polyurethane films were analyzed to investigate additive-coating compatibility. Coatings containing photoactive additives were subjected to self-decontamination challenges against representative chemical contaminants and the effects of additive loading concentration, light exposure, and time on chemical decontamination are reported. Covalent attachment of an ethylene glycol tail to C 60 improved its solubility and dispersion in a hydrophobic polyurethane matrix. Decomposition products resulting from oxidation were observed in addition to a direct correlation between additive loading concentration and decomposition of surface-residing contaminants. The degradation pathways deduced from contaminant challenge byproduct analyses are detailed.

Air Activated Self‐Decontaminating Polydicyclopentadiene PolyHIPE Foams for Rapid Decontamination of Chemical Warfare Agents

“…The retention time of intact Demeton‐S was 7.9 min and extract analysis of unaged foams exhibited this characteristic peak (*); however, in aged foam extracts this peak was absent and replaced with a byproduct peak at 4.5 min. The mass spectrum of this peak indicated the vinyl elimination product of Demeton‐S (**) that is generated from Demeton‐S sulfoxide and its presence may be a consequence of thermal degradation due to the high inlet temperatures of the GC‐MS protocol . Demeton‐S sulfone also formed as a result of interaction with aged foams and started to appear in extracts at the 2 h exposure level (Figure S7, Supporting Information).…”

“…The mass spectrum of this peak indicated the vinyl elimination product of Demeton-S (**) that is generated from Demeton-S sulfoxide and its presence may be a consequence of thermal degradation due to the high inlet temperatures of the GC-MS protocol. [12] Demeton-S sulfone also formed as a result of interaction with aged foams and started to appear in extracts at the 2 h exposure level ( Figure S7, Supporting Information). The 30 min CEES challenges exhibited similar behavior: unaged foam extracts contained only intact CEES, which eluted at 2.1 min ( †), while aged foam extracts contained the CEES sulfoxide byproduct, eluting at 4.0 min ( ‡), in addition to a reduced peak area representing intact CEES.…”

“…Research motivated by self-cleaning filtration media has included investigations into catalytic technologies such as polyoxometallates (POMs), [9][10][11][12][13] metalorganic frameworks (MOFs), [4,[14][15][16][17] metal oxides, [18][19][20][21][22][23][24] and, more recently, nucleophilic polymers. [25][26][27] POMs, MOFs, and metal oxides are all limited in application as powders or require incorporation into a supportive structure that limits the reactive surface area.…”

Surface Characterization, Antimicrobial Effectiveness, and Human Cell Response for a Biomedical Grade Polyurethane Blended with a Mixed Soft Block PTMO-Quat/PEG Copolyoxetane Polyurethane

“…For the first run, R1, a change in slope at −77 °C for Tecoflex and UP-C12-50-T blends is assigned to the PTMO T g (Table 2, Figure S4, R1). 46,47 A second transition at 15 °C for Tecoflex is assigned to T m for PTMO. This transition is weak in run R2 that was carried out after recooling.…”

Distribution of quaternary ammonium salt encapsulated polyoxometalates in polyurethane films

“…paint, to impart additional properties such as water repellency, selfhealing, antimicrobial activity, [2,3] and chemical agent decontamination. [4,5] While many approaches exist to impart multi-functionality, incorporation of additives into preexisting coating formulations offers the potential to create a functionalized coating surface while maintaining original properties. In this context, the distribution of molecular additives, including nanoparticles, [6] in solution and polymers, such as polyurethane, [7,8] has been recently studied.…”