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OSTE polymers is a novel polymer platform comprising Off-Stoichiometry Thiol-Enes (OSTE) and Off-stoichiometry thiol-ene-epoxies (OSTE+). They were originally developed by the group of Micro and Nanosystems〔() MICROFLUIDICS & LAB-ON-CHIP〕 at the Royal Institute of Technology (KTH) in Stockholm, Sweden, to bridge the gap between research prototyping and commercial production of microfluidics devices〔() Lab Chip , 2011 , 11, 3136〕 and later adapted for commercial applications by the Swedish start-up Mercene Labs AB.〔() Mercene Labs AB homepage〕 The OSTE polymers comprise off-stoichiometry blends of thiols and allyls. After complete polymerization, typically by UV micromolding, the polymer articles contain a well-defined number of unreacted thiol or allyls groups both on the surface and in the bulk. These surface anchors can be used for subsequent direct surface modification or bonding.〔() Lab Chip , 2011 , 11, 3136〕 In later versions epoxy monomers were added to form ternary thiol-ene-epoxy monomer systems (OSTE+), where the epoxy in a second step reacts with the excess of thiols creating a final polymer article that is completely inert.〔() Saharil , Lab Chip 12, 3032-3035 (2012)〕 Some of the critical features of OSTE+ polymers include uncomplicated and rapid fabrication of complex structures in a standard chemistry labs, hydrophilic native surface properties and covalent bonding via latent epoxy chemistry.〔() Vastesson, Proc. IEEE Transducers 2013 Barcelona, 408-411 (2013)〕 ==Reaction Mechanism== The OSTE polymers are cured via a rapid thiol-ene “Click” reaction between thiols and allyls. The thiols and allyls react in a perfectly alternating fashion and has a very high conversion rate (up to 99%),〔() C.E.Hoyle and C.N.Bowman,Thiol-ene click chemistry, Angew. Chem., Int. Ed., 2010, 49, 1540〕 the initial off-stoichiometry of the monomers will exactly define the number off unreacted groups left after the polymerization. With the right choice of monomers very high off-stoichiometry ratios can be attained while maintaining good mechanical properties 〔text of the citation〕 The off-stoichiometry thiol-ene-epoxies, or OSTE+ polymers, are created in a two-step curing process where a first rapid thiol-ene reaction defines the geometric shape of the polymer while leaving an excess of thiols and all the epoxy unreacted. In a second step all the remaining thiol groups and the epoxy groups are reacted to form an inert polymer. (figure below ) 〔() Saharil, Journal of Micromechanics and Microengineering 23, 025021 (2013)〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「OSTE polymers」の詳細全文を読む スポンサード リンク
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