Combinatorial chemistry is a relatively new experimental methodology developed by academics and r... more Combinatorial chemistry is a relatively new experimental methodology developed by academics and researchers in the pharmaceutical industry to reduce the time and cost associated with drug development. Basically, combinatorial chemistry involves the rapid synthesis and evaluation of large numbers of compounds in parallel using robotics, rapid analytical instrumentation, and data management software. More recently, the principles of combinatorial chemistry have been applied to materials development, and interest in this area is increasing rapidly. This interest can be attributed to the potential for obtaining a major competitive advantage by implementing a combinatorial approach. This document provides an introduction to combinatorial materials science and provides a review of efforts aimed at developing combinatorial workflows for coating development. While the application of combinatorial methods to coating development is still in its infancy, full combinatorial workflows have been developed within a few different organizations.
Combinatorial and high throughput experimental methods are being applied to the design and develo... more Combinatorial and high throughput experimental methods are being applied to the design and development of novel polymers and coatings used in a number of application areas. Methods have been developed for polymer synthesis and screening and for the development of polymer thin film and coating libraries and the screening of these libraries for key properties such as surface energy and modulus. Combinatorial and high throughput methods enable the efficient exploration of a large number of compositional variables over a wide range. In the development of coatings for use in the marine environment, the key challenge is in the development of screening methods that can predict good performance. A number of assays are under development that will permit the rapid screening of the interaction of coatings with representative marine organisms.
Novel soy-based thiols and enes were synthesized and characterized. Then, soy-based thiol–ene UV-... more Novel soy-based thiols and enes were synthesized and characterized. Then, soy-based thiol–ene UV-curable coatings were formulated and their coating physiochemical properties were investigated in detail. The use of biorenewable resources, combined with environmentally friendly UV-curable technology, provides a “green + green” solution to the stricter regulations in the coatings industry. Novel soy-based thiols and enes were synthesized through the Lewis acid-catalyzed ring opening reaction of epoxidized soybean oil with multifunctional thiols or hydroxyl functional allyl compounds. FTIR and NMR confirmed the formation of the target compounds. The soy-based thiols and enes were formulated with petrochemical-based enes and thiols, respectively, to make thiol–ene UV-curable coatings. Typical coating film properties, thermal properties, and photopolymerization kinetics of these coatings were studied. Soy-based thiol–ene coatings having lower functionality thiols and enes have poor UV curability and coating properties, which was attributed to the lower crosslink density. Soy-based thiols and enes with higher functionality can be UV-cured in combination with petrochemical-based enes or thiols even without the presence of free radical photoinitiators. Better coating film properties were obtained from these higher functionality thiol–ene systems that were toughened by commercial hyperbranched acrylates.
A trimethylsilane-based coating was investigated as a pretreatment for Al-2024 T3 in a novel Mg-r... more A trimethylsilane-based coating was investigated as a pretreatment for Al-2024 T3 in a novel Mg-rich primer corrosion prevention system. SiC-based thin films were deposited onto Al substrates by plasma-enhanced chemical vapor deposition (PECVD). A screening study of the ...
... Alex Kugel a, Bret Chisholm *ab, Scott Ebert b, Michael Jepperson b, Laura Jarabek b and Shan... more ... Alex Kugel a, Bret Chisholm *ab, Scott Ebert b, Michael Jepperson b, Laura Jarabek b and Shane Stafslien b. a Department of Coatings and Polymeric ... in 2.0 g methanol and 138 µL (0.0064 equivalents N–H) DETA in an 8 mL scintillation vial using a Vortex-Genie lab mixer by ...
A high-throughput bacterial biofilm retention screening method has been augmented to facilitate t... more A high-throughput bacterial biofilm retention screening method has been augmented to facilitate the rapid analysis and down-selection of fouling-release coatings for identification of promising candidates. Coatings were cast in modified 24-well tissue culture plates and inoculated with the marine bacterium Cytophaga lytica for attachment and biofilm growth. Biofilms retained after rinsing with deionised water were dried at ambient laboratory conditions. During the drying process, retained biofilms retracted through a surface de-wetting phenomenon on the hydrophobic silicone surfaces. The retracted biofilms were stained with crystal violet, imaged, and analysed for percentage coverage. Two sets of experimental fouling-release coatings were analysed with the high-throughput biofilm retention and retraction assay (HTBRRA). The first set consisted of a series of model polysiloxane coatings that were systematically varied with respect to ratios of low and high MW silanol-terminated PDMS, level of cross-linker, and amount of silicone oil. The second set consisted of cross-linked PDMS-polyurethane coatings varied with respect to the MW of the PDMS and end group functionality. For the model polysiloxane coatings, HTBRRA results were compared to data obtained from field immersion testing at the Indian River Lagoon at the Florida Institute of Technology. The percentage coverage calculations of retracted biofilms correlated well to barnacle adhesion strength in the field (R2 = 0.82) and accurately identified the best and poorest performing coating compositions. For the cross-linked PDMS-polyurethane coatings, the HTBRRA results were compared to combinatorial pseudobarnacle pull-off adhesion data and good agreement in performance was observed. Details of the developed assay and its implications in the rapid discovery of new fouling-release coatings are discussed.
Combinatorial chemistry is a relatively new experimental methodology developed by academics and r... more Combinatorial chemistry is a relatively new experimental methodology developed by academics and researchers in the pharmaceutical industry to reduce the time and cost associated with drug development. Basically, combinatorial chemistry involves the rapid synthesis and evaluation of large numbers of compounds in parallel using robotics, rapid analytical instrumentation, and data management software. More recently, the principles of combinatorial chemistry have been applied to materials development, and interest in this area is increasing rapidly. This interest can be attributed to the potential for obtaining a major competitive advantage by implementing a combinatorial approach. This document provides an introduction to combinatorial materials science and provides a review of efforts aimed at developing combinatorial workflows for coating development. While the application of combinatorial methods to coating development is still in its infancy, full combinatorial workflows have been developed within a few different organizations.
Combinatorial and high throughput experimental methods are being applied to the design and develo... more Combinatorial and high throughput experimental methods are being applied to the design and development of novel polymers and coatings used in a number of application areas. Methods have been developed for polymer synthesis and screening and for the development of polymer thin film and coating libraries and the screening of these libraries for key properties such as surface energy and modulus. Combinatorial and high throughput methods enable the efficient exploration of a large number of compositional variables over a wide range. In the development of coatings for use in the marine environment, the key challenge is in the development of screening methods that can predict good performance. A number of assays are under development that will permit the rapid screening of the interaction of coatings with representative marine organisms.
Novel soy-based thiols and enes were synthesized and characterized. Then, soy-based thiol–ene UV-... more Novel soy-based thiols and enes were synthesized and characterized. Then, soy-based thiol–ene UV-curable coatings were formulated and their coating physiochemical properties were investigated in detail. The use of biorenewable resources, combined with environmentally friendly UV-curable technology, provides a “green + green” solution to the stricter regulations in the coatings industry. Novel soy-based thiols and enes were synthesized through the Lewis acid-catalyzed ring opening reaction of epoxidized soybean oil with multifunctional thiols or hydroxyl functional allyl compounds. FTIR and NMR confirmed the formation of the target compounds. The soy-based thiols and enes were formulated with petrochemical-based enes and thiols, respectively, to make thiol–ene UV-curable coatings. Typical coating film properties, thermal properties, and photopolymerization kinetics of these coatings were studied. Soy-based thiol–ene coatings having lower functionality thiols and enes have poor UV curability and coating properties, which was attributed to the lower crosslink density. Soy-based thiols and enes with higher functionality can be UV-cured in combination with petrochemical-based enes or thiols even without the presence of free radical photoinitiators. Better coating film properties were obtained from these higher functionality thiol–ene systems that were toughened by commercial hyperbranched acrylates.
A trimethylsilane-based coating was investigated as a pretreatment for Al-2024 T3 in a novel Mg-r... more A trimethylsilane-based coating was investigated as a pretreatment for Al-2024 T3 in a novel Mg-rich primer corrosion prevention system. SiC-based thin films were deposited onto Al substrates by plasma-enhanced chemical vapor deposition (PECVD). A screening study of the ...
... Alex Kugel a, Bret Chisholm *ab, Scott Ebert b, Michael Jepperson b, Laura Jarabek b and Shan... more ... Alex Kugel a, Bret Chisholm *ab, Scott Ebert b, Michael Jepperson b, Laura Jarabek b and Shane Stafslien b. a Department of Coatings and Polymeric ... in 2.0 g methanol and 138 µL (0.0064 equivalents N–H) DETA in an 8 mL scintillation vial using a Vortex-Genie lab mixer by ...
A high-throughput bacterial biofilm retention screening method has been augmented to facilitate t... more A high-throughput bacterial biofilm retention screening method has been augmented to facilitate the rapid analysis and down-selection of fouling-release coatings for identification of promising candidates. Coatings were cast in modified 24-well tissue culture plates and inoculated with the marine bacterium Cytophaga lytica for attachment and biofilm growth. Biofilms retained after rinsing with deionised water were dried at ambient laboratory conditions. During the drying process, retained biofilms retracted through a surface de-wetting phenomenon on the hydrophobic silicone surfaces. The retracted biofilms were stained with crystal violet, imaged, and analysed for percentage coverage. Two sets of experimental fouling-release coatings were analysed with the high-throughput biofilm retention and retraction assay (HTBRRA). The first set consisted of a series of model polysiloxane coatings that were systematically varied with respect to ratios of low and high MW silanol-terminated PDMS, level of cross-linker, and amount of silicone oil. The second set consisted of cross-linked PDMS-polyurethane coatings varied with respect to the MW of the PDMS and end group functionality. For the model polysiloxane coatings, HTBRRA results were compared to data obtained from field immersion testing at the Indian River Lagoon at the Florida Institute of Technology. The percentage coverage calculations of retracted biofilms correlated well to barnacle adhesion strength in the field (R2 = 0.82) and accurately identified the best and poorest performing coating compositions. For the cross-linked PDMS-polyurethane coatings, the HTBRRA results were compared to combinatorial pseudobarnacle pull-off adhesion data and good agreement in performance was observed. Details of the developed assay and its implications in the rapid discovery of new fouling-release coatings are discussed.
Uploads
Papers by Bret Chisholm